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Discussion Starter #1 (Edited)
"Babe" is my Hakim sniper and is working its' way up to be something awesome indeed.

I have an all original Hakim with bayonet in perfect shape I intend to keep milspec. On a good day, it shoots 3" groups at 200yds with iron sights and the occasional flyer.

"Babe" was a find on Gunbroker.com where it sat for a week with no bids. Undoubtedly, the "bubba" attempt at putting a scope on it scared everyone off. It looked otherwise very clean so I threw the $400 bid on it at the last minute and got it.

The bore was crisp and shiny with distinct rifling. The metal all over was excellent. The stock, despite some light sanding and oiling work is in exceptional condition and a nice looking hunk of wood. It had a little cosmo still hiding in the deep recesses and the bolt and firing pin had never been taken apart and cleaned. Lack of powder residue said she wasn't fired much as it was cleaner than expected.

Bubba did a very nice detailed job of inletting the stock on the left of the receiver and mounting a 4"x6" plate of aircraft aluminum to the receiver. It was very carefully machined for the Weaver scope rings and very fine quality workmanship. It had a nice anodized black finish.
Unfortunately, all good intentions aside, Bubba had no grasp on what he was doing!

The scope that came on it was $50 crap. 9X is useless compared to iron sights at anything under 250yds anyway. The rings were cheap.
The four carefully countersunk hex head 4x32 screws holding it to the frame immediately worked loose every ten rounds. The half pound of lead he filled the cleaning kit holes in the stock with did little more than make it heavy. It shot groups as good as my other one with iron sights but wouldn't hold zero worth diddly with the scope.
I proved her out with iron sights and was satisfied the bore and all function was good to very good.

Bound and determined to make a good sniper out of it just for shits and giggles, I started the process of making changes.
A very healthy dose of locktight cured the problem with the mounting plate. It required a torch to heat them up again to get them off.
The mount plate has not moved a hair since and the pins I intended for that may be unnecessary.

Next was choosing a quality scope that suited me for my 200 yard range (240 to the berm).
Borrowed my neighbors 8x26 Barska Swat scope and I was impressed.
It still wasn't what I wanted but I liked the scope.
A little web surfing and I found the 8x32 Barska Swat Tactical scope with rangefinder focus and illuminated reticle cheaper than what he paid for his! Anything more powerful would have been far more than I was prepared to invest and at $199, the Barska seemed up to the task. 32 power is strong enough to easily see the holes in the target at 200 yds.

Being a much larger scope, and with the additional turret on the left side, it didn't fit on the mount. I had to have my machinist mill out a 1.5" hole to accommodate the left rangefinder knob.
With that and the 30mm tube, the high profile rings that came with it ended up placing the center of the scope 3/4" offset to the right, a parallax problem indeed. Test firing of that showed a considerable adjustment was needed left to right for a 50yd range difference.

The thumb screw Weaver style Barska rings just wouldn't stay tight on the mount. If they loosened up just slightly, elevation would change by a foot or more.
Seeing how critical this was, I ordered the lowest profile rings they had (a paltry $8.95) The thumb screw problem was even worse with that set and they refused to stay tight through ten rounds.

Back to the machinist. I calculated 3mm of offset to center the vertical line of the scope dead center with the bore. It worked out just right milling a 3mm slot for each ring blade into the mount and milling off the tab on the rings to make them flat and remove the screw clamps entirely. They were then welded onto the mount. The vertical line is now perfectly dead center with the bore and the bottom of the scope clears the slide by a half inch. It certainly isn't going anywhere.

Another problem showed up with brass dinging the bottom of the scope. A 3" galvanized steel deflector plate screwed to the mount under the scope cured that.

A Harris adjustable bi pod fits perfectly using a longer bolt to attach it to the front where the spring for the front clamp/bayonet lug attaches. I had to grind down the bolt a little to keep it from touching the barrel after going through the nut in the stock. The single bolt seems to be enough to keep it in place. It sets up just right on the bench but bounces a bit. With the legs extended and laying prone in the sand, gun no move! She slides back gently and stays right on target, enough for a quick second, third, forth shot... In fact, you can pump out about a shot a second with very little movement. A slightly better bi pod may be in order as my son had laid claim to this one and wants it on the other Hakim. Since mounting does no damage and makes no physical changes, he can have it.

The Hakim has little recoil anyway but since this is a shits and giggles project, I just had to buy a mercury filled recoil suppressor for the stock: http://www.precisionreloading.com/recoilsuppressors.htm
The MR100345 10oz 3/4x5" was my choice.
As the existing holes, which happen to be 3/4" converged on the wrong angle (thought I would get away without drilling) I filled the holes with epoxy based wood filler and let it harden. I then concocted a jig to drill a 3/4x 5 3/4" hole parallel to the bottom of the stock and slid the tube into place.
OH YEAH! This DOES make a real difference! It has no "crack" to the recoil, just a gentle push. Bare shoulder shooting is a total pleasure.
It's a little more than a .22 but not so much as you can even notice it.
I'm still looking for the right gel pad for the butt plate just to keep it from sliding on the shoulder. The metal plate just wants to slip a bit.

Wed afternoon, time for the first test run with the current evolution.
It was absolutely dead calm with no wind at all when we got there and a slight overcast. I threw 5 clay birds onto the berm when we set up the targets at 200yds.

Lining up the scope with the iron sights, I was about 6" high but hit the left/right dead center on the first adjustment. A couple turns on the elevation dial brought it down and the first clay shattered.
I marched it right across taking each one in turn with one shot including the one laying flat with only the side exposed!
They clays were no match! One shot, one clay!

I could see the guy in the next booth watching with a keen eye so I invited him to try it. He was beside himself when his first shot hit a 2" rock out on the berm. He nailed a couple more in succession burning off a magazine. It proved she was dead on and I wasn't just getting lucky.

I commenced to working on the remnants of the busted clays.
A half of a clay was a one shot kill and half of that was another.
That is roughly the size of a 50 cent piece at 240 yds! I keep shooting the pieces until there was nothing left to shoot at and hitting them consistently. Golf balls at 240 yds? Wouldn't have been a problem!
I took a felt pen and marked off the settings on the scope dials.

I started working on a nice 2" group on paper at 200yds. Slight change in elevation and it had to come down 3". By then, a breeze started stirring with the usual right drift this range often gets when the breeze deflects off the left berm.

The major problem I have on this range is wind. It plays hell with 8mm, far more so than 7.62x54. 8mm seems to ride the surf and the least little gust of wind blows them all over the map. I no sooner had the 6" right drift accounted for and it changed again. We had to give up as the wind increased and the group spread. There is just no holding any kind of group or predictable impact point with the least little wind and impossible to calculate as it is different at the target than at the booth. Yugo 7.62x54 heavy ball seems to plow through it a lot better. It must have something to do with the shape of the bullet and the sharp taper of the 8mm must be a factor.

Fri. afternoon. The breeze seemed calm and I just had to have another go at it. Walking the targets out, I quickly realized that it was as strong as Wed with unpredictable little gusts. There is a bad hole on this range at about 180 yds where smoke will swirl in all directions with the least little wind and I promptly found just that. Hold your breath for the wind to calm and take the shot is about all you can do.
One little puff of wind throws it a foot off.
Zero was still dead on right out of the case when I started off whacking dirt clumps on the berm.
I did manage to plant a couple right on the 2x2 cross drawn on the paper but the overall group and flyers made it an exercise in futility so we quit. I did put a few through the FN49 and they were not quite as tight as usual. I like the FN49 but it ain't no Hakim!

I have yet to finish a few things. I can't locktight the screws on the scope rings yet and until I do so they continue to loosen up slightly.
Since Bubba removed the wire springs from the bolts on the trigger group, they tend to get very loose very fast and require a tweak with a screw driver every 20 rounds. Forget to do that and they are at least 4-6 full turns loose! It's either make new spring wires or some kind of lock screw like a K98. Have yet to ponder that.

Maybe next week I can get around to the stress free pillar glass bedding job with Devcon 10110 epoxy and find a way to torque those bolts down and keep them tight. I think that has much to do with accuracy as it goes to crap when they loosen up.

I still need a close examination of the muzzle brake and maybe a crown job to smooth out the business end of the barrel. That may need something done but I'm not to that point for a while yet.

There is an elevation shift as it heats up. I have yet to be able to calculate the shift until I get a sustained session with no wind where I can hold a group. I'm also not sure what effect powder residue accumulation in the barrel is causing. I do think it may be a factor as clean and cold vs. hot and dirty (300 rds later) may be spreading the group. We know the point where melted polymer and lacquer coating on the cases start to jam the case and prevent extraction (having already replaced a broken extractor on the other one). Only drilling it out with a brush soaked in lacquer thinner seems to get it out, one brush for the case area of the chamber and one for the throat area.
Sparkling clean, it's good for about 300 rds before you know it's time to quit. By 300 rounds, a chambered bullet will eject covered in black so you know there is considerable crap build up in the throat.

"Babe" is turning into quite a little project and will be well worth $1250 when I am satisfied. But then, being able to whack a golf ball at 240 yds cold out of the case makes her one mean motor scooter!
Besides, with the sun shade on the scope and the bi pod ... it sure do look awesome and gets everyone's attention on the range!
(no batteries for the camera but I will get a picture up soon)

Unfortunately, there is only one 600 yard range in the state and it is quite a drive. I do believe Babe is quite capable of some serious distance. The scope is good enough to see the eyeballs on deer at 600 yds across the field in back of my house and I could easily make a head shot on one if I knew the bullet drop.

Don't let anyone tell you a Hakim isn't a sniper! This thing has real serious potential when I work out all the bugs. Just don't let Bubba do the work for you as "critical" is measured in millimeters and single degrees to get accuracy. I'll quit tinkering when I achieve consistent 1" groups at 200 yds. ... with milsurp ammo!
 
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Sounds like a nice project! post some pics if you can. And about the trigger guard screws, just use some blue lock-tight and they won't budge. But you'll still be able to loosen them when you need to.
 

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Discussion Starter #3
A little more work

Got the case deflector mounted to the scope mount today. That should keep them from dinging the scope up.

Found something interesting with the muzzle brake cap...
On close inspection, I found it loose as a goose despite seeing wire in the slot. Wobbles back and forth quite a bit.
I had to compare it with the other one to figure out the spring, that was the rest of that wire, was broken off and missing.
After a bit of a fight, I got the remaining wire out of the slot and was able to unscrew the end cap. Threads have a real sloppy fit. Screwing it down tight, it goes a half turn too far and the ports don't line up.
The bullet has considerable clearance passing through it as the hole diameter is much bigger but, having it wobble around could effect the bullet with an uneven pressure release behind it.

So... as long as it's off. I am ordering an 8mm lapping tool from Midway. I want to lap the end of the barrel before I put in a new cap and spring I am ordering from Numrich, they list them.
May as well as I plan to order a hammer and sear so I have another set to polish down nice and smooth, in case I go a little too far!

The design of the muzzle brake is as good if not better than any you can buy so no sense changing it. Lapping the end to make sure it is perfectly concentric will be in order once I get one seated nice and tight.

I would still love to find an old retired Egyptian army armorer who can shed some light on these things. Several emails to their army website technical institute received no reply.
I'm sure they must have some tricks to accurize and fine tune these rifles. It would also be nice to find out what role and squad assignment they played. I can see it as a long distance dune to dune heavy support rifle. With that bi pod on it, you can thump away like a BAR!
 

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Discussion Starter #4
Pics

Let's see if the pics come out ok
 

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come on, BARSKA, you gotta be kidding. start shopping. :D
 

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Discussion Starter #7
come on, BARSKA, you gotta be kidding. start shopping. :D
Well... my pockets are not all that deep...
The objective was being able to clearly see the holes in a 200yd target without putting it down and going to my telescope.
After trying a 26X and finding it wasn't quite enough, I bought the 32x.
When you get over 30x, choices are limited and the really good stuff is way more than I have intentions of spending, as in really big bucks!

The Barska is quite adequate. It is crystal clear and very bright even at 32x. It is holding zero perfectly. It hasn't broke yet! I can watch the bullet impact. Click stops on the turret allow precise adjustment.
The rings are pure crap. That's why they are welded to the mount. I have no need to take the scope off. I am quite satisfied being able to hit something the size of a golf ball at 240yds on the berm and see the hit. Seeing as that's as far as I can go on my range, it's more than adequate for the job.

It would be nice to determine the real reach potential of the gun but I doubt I will ever get the chance to try it out on a really long range as there just aren't any around here. There are still a few remaining items to tune up for accuracy. I am still pondering how to bed it as the actual contact areas with the stock are not all that much and how much wood to take out is questionable. I'm not sure there is enough wood to put pillars front and rear or just let the epoxy fill the holes and re-drill.

Don't forget, I'm shooting milsurp and while that 80's Yugo is nice stuff ... Once I get it really tuned up, I'll spring for a box or two of new factory loads. Can't afford to drop a couple hundred of them every time I go...

There must be some old retired Egyptian Army armorers who worked on these guns and really knew what to do with them. The problem is finding one, who can speak English, to get the kind of information we could all use to make them better. I'm open to proven suggestion rather than experimentation. Don't want to do something I can't take back!
 

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anyway..... i hope you have good luck with the barska, i bought a barska set of binocs from SG once, total peace of crap. knew a cop that bought a baska sniper scope like yours, put it on his 308 savage "sniper", it crapped out really fast. i recommend anyone get a tasco/bushnell/simmons etc, before a barska, but we'll wait and see. good luck.
 

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nice job! btw do you have a closeup of the scope mounting system?
just curious about the setup.
 

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Discussion Starter #10 (Edited)
Rear monopod

monopod

Having trouble holding that heavy rifle steady even with a bipod or sandbag rest on the front end?

Bubba’s Squirrel Gun is starting to approach the weight and size of a BAR and 32x magnification makes it a wee bit tough to hold steady at distance even with the bipod and pulled tight to the shoulder.

Son recalled something he saw and hunted it down.
Original 1922 BAR
http://world.guns.ru/machine/bar1922.jpg

Note the rear adjustable monopod support.

Finding and building a suitable approximation of this looked like a difficult task.
Numerous trips through the hardware store with a wary eye failed to locate anything that remotely resembled the necessary parts.
Then, while digging through some boxes in the basement, I tripped across a treasure stashed away that had not been used.

Reiker Easy Fan Brace Cat #33300
http://www.galesburgelectric.com/Re...Duty-Brace-Support-p-2258.html#Detailed_Image

http://www.passandseymour.com/pdf/Q02.pdf

This hardware item proved to be the perfect choice for modification.
1. Unscrew right end, tap out the screw cap that fits in the barrel end.
2. Remove screws and barrel
3. Locate 3/4x6” flat steel stock
4. Locate a 1/2x13 nut
5. Bend flat stock into a U shape, 2x2x2
6. Weld nut to flat stock in the middle
7. Cut a rubber liner (an old mouse pad was used for this) 1/8” thick by 3/4x6”
8. Glue rubber liner into U
9. Cut threaded rod to 3 ¼”
10. Cut barrel to 3 1/8”
11. Replace the threaded end cap into barrel = 3 ¼”

Note that the angle created by the bracket at the bottom matches the angle of the stock.
Glue rubber feet (again from mouse pad material) to the front legs.
The conical points on the bottom of the casting will dig into the wood on the bench for a solid slip proof base.
Elevation adjustments can be dialed in by simply rotating the barrel portion to screw the butt up or down with very precise adjustment.
Combined with a bipod or Caldwell sandbag rest, this is a solid and stable as an artillery piece!

The longer piece of threaded rod you cut off is perfect for use with the bipod legs extended for a higher mount while laying prone. Simply unscrew the short rod and replace with the longer one.
 

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Discussion Starter #11
missed a pic

stand close
 

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Discussion Starter #12
scopemount

The aluminum plate is 1/4" thick, top part was 1/2" thick where the rings mount, 4" wide, 4 1/8" high.
Stock inletting was flush with the bottom of receiver frame.
4 4x32 hex head bolts were countersunk into aluminum, drilled and tapped into left side of receiver frame. These were filed flat on the inside of the frame but do not interfere with anything.
There was evidence of some Locktite on the threads but they rattled loose after ten rounds. I was going to insert two pins into the thick block in the middle of the receiver frame but a much more liberal application of Locktite, including around the head of the bolts, seems to be holding.
It took much heating with a torch to get one out!

The hole for the turret is 1 3/8".
The low profile rings were milled flat on the rear and the clamp and thumb screw removed. A 3mm deep slot matching the base of the ring was milled into the plate and the rings welded on.
Note the anodizing changed color from the heat. That will get a paint job when I take it apart again. Intentions of shooting it tomorrow so that will have to wait.

The deflector plate is just a thin piece of galvanized sheet metal with a little tab bent over for two 4x32 screws tapped into the plate.
You can see the ding in the scope from the ejected brass which makes this necessary.

It ain't real pretty but that's what I started with so it will be what it will be. At least now, it is rock solid and the plate don't come loose nor the rings loosen up.
It may require a little Locktite on the screws in the rings as I already partially stripped one. Longer screws and nuts may be in order. They did loosen up a little after 50 rounds.

I want to be assured that I can take it out of the case and have the scope dead on zeroed and maintain a rock solid perfect zero. That's getting there quickly.

The crown lapping tool is in the mail along with the new muzzle brake cap and spring as well as a spare hammer and sear for some fine honing to a smooth and light let off.

Bedding and securing the trigger group bolts so they don't loosen up will wait until the weather gets bad and I can't visit the range.
For now, it's a turn or two with a screw driver every 20 rounds or so.
 

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wow, looks like a very sturdy setup!
thanks for posting the update.
 

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Discussion Starter #14
Muzzle Brake cap

Found an interesting point all Hakim owners need to take a look at...

While moving on up to the business end, I had noted that the muzzle brake end cap wobbled around quite a bit and the spring clamp was broken.

Numrich has these:
http://www.e-gunparts.com/products.asp?chrMasterModel=4040zEGYPTIAN 8MM&MC=
part 1032070 and the lock spring 1032110

Figuring I was going to attack these in some way, I ordered both which arrived yesterday.
The one already on the gun was in better shape as it appears the Numrich part was taken off with hammer and chisel.

Comparing all three of these cast pieces, it is quickly obvious they are very crude and the machining is not very precise.

I have been doing some study on barrel crowning and how uneven gas pressures from an asymmetrical crown induces yaw in the rear of the bullet as it leaves the muzzle. This is a major cause of FLYERS and spready groups.

While the muzzle brake cap has about .002 clearance around the bullet and the bullet does not contact it as it passes through, being out of true does open the possibility for unequal gas pressures inducing yaw in the bullet.
It is impossible to tell how much gas pressure vents from the front behind the bullet after passing through the lower portion of the brake and vents in the cap but it is probably enough to effect accuracy.
I had plans on lapping this with a crown lapping tool anyway which is why I got a spare.

A trip to the machine shop today was immediately revealing.
The cap was placed in a lathe chuck where it was immediately obvious that it was way out of round.
The rear face, towards the barrel, was perfectly true and received only a very light trim to smooth out some of the casting marks.

The front end had a very visible wobble in the chuck and the inner bore appeared to have abnormalities.
This was more obvious on a pass with the cutter that showed it definitely was not 90 degrees true to the bore or flat.
After finding an appropriate size bit to ream the bore, the first pass from the front end bucked in the chuck showing it was out of round and off center. It cleaned up true to center without removing much.
It was obviously off center as one side cut clean while the other side still shows a little copper residue inside. It may yet require another oversize reaming. As it does not contact the bullet, opening it up a little more to get it symmetrical and true to the bore wouldn't hurt anything. If anything, it has to be an improvement!

The inner cavity, formed by cutting the gas vents, had a considerable accumulation of corroded copper residue including visible lumps of build up. It took ammonia and steel wool worked around in there for a while and a good soak in Formbie's furniture stripper to finally get the junk out. This buildup was pronounced enough that it certainly had to cause turbulence and uneven gas pressures. There was a visible and rather large lump of green junk on one side by the vent slot.

What appears to be an inherently poor design, from the machining of the vent slots and loose fitting threads, leaves an uneven mating surface for the cap to mate with the bottom of the muzzle brake.
As previously noted, it does not screw down tight without passing the point where the vents line up. In the proper position, there is a slight gap where it can wobble in the threads. Allowing the cap to wobble around can't be good.
The first attempt to correct this will be with teflon thread tape vs Locktite as I still want to be able to remove it.

Regular inspection and cleaning of the inside may be required.

When the 8mm lapping tool arrives, I will lap front and rear of the cap as well as the barrel end inside the muzzle brake.

This should have considerable effect on accuracy as the plainly obvious flaws have to induce problems. It may be satisfactory for military spec but it certainly can't be considered the best design for long range accuracy.
Removing the muzzle brake entirely and having it replaced with a high quality one would be expensive. While the existing component looks very effective, it definitely deserves close attention and some tune up work.

I absolutely intend to follow the same procedure on the other Hakim and the spare cap.

I would strongly suggest that any Hakim owner pay particular attention to this and do the same! We may note a considerable increase in accuracy and smaller group sizes with fewer flyers.
 

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Discussion Starter #15
Muzzle brake cap update

Received the lapping tool I ordered:
http://www.midwayusa.com/eproductpage.exe/showproduct?saleitemid=824099&t=11082005
R W Hart Barrel Muzzle Crown Lapping Tool Insert #C 30 to 8mm Caliber Brass

A few minutes hand turning this with valve grinding compound was enough to put a nice 11 degree chamfer on both ends of the muzzle brake cap.

It is a little difficult to get it down inside the muzzle brake and do the barrel end but there is just enough sticking out to twirl it with your fingers and do the job. It takes a little longer to lap in the chamfer as the metal is much harder.

Barrel end and muzzle brake cap are now lapped in.

The loose fitting cap wobbling around in the threads has become even more of a problem after the extensive cleaning to remove the grinding compound. The coarse threads just have too much wiggle room.
This is looking like another trip to the lathe.
The cap only seats tight in the threads 1/4 turn past the wire slot where it looks to be .001" too loose. In order to gain the remaining 3/4 turn to again bring it back to that mark and lock it in tight, it looks like trimming the barrel side of the ring on the cap is in order.
Teflon thread tape did secure it with several wraps but that is not an acceptable solution.
 

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Wow DB, following this thread has been a rude awakening. I like to think I can make minor adjustments and repairs to my guns, but man, you must be THE Gunsmith's Gunsmith. My work is basically limited to hand tools :) I will send some parts up to my Grandfather (also an avid collector/shooter) to take a couple .01's off to help fit, but .001's are beyond my rekoning. Most households would wish for a mechanic in the family, maybe now-a-days a computer tech (Which, Unfortunately, I happen to be), but I wish I had you in the family. Obviously you are, or were, a highly skilled machinist. Ever thought about contacting the Dicovery channel, maybe Science channel for How It's Made, or the Military channel? No mocking here, I mean it. Keep up the great naratives/instructionals, but probably over the heads of most of us here. Your fan, Marvell.
 

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Discussion Starter #17
Hakim Muzzle Cap update

Today is the day to test out the results... range this afternoon!

The whole problem has become very interesting indeed!
The problem stems from a poor choice of threads for the cap being coarse enough to allow movement when they are bare metal clean.
They are simply a coarse thread with a lot of play and slop.

Went back to the machine shop and chucked the cap in the lathe.
We already knew from the previous reaming that the front portion was not true to center. The outer end was shaved .002 until it was rotating true. It was then reversed chucking the front end in the lathe.
We took the ring portion down .002 to true up the surface that mates with the end of the brake. It now had even more gap when the gas port slots line up correctly. Some calculations with a micrometer showed we would have to almost completely remove the ring to get the remaining 3/4 turn on it to bring it back around to the index mark and line up. Too much! We also calculated that further trimming would bring it all too close to the end of the threads in the brake where it would bottom out. Further trimming on the cap is out.

Next came the search for a shim, which we figured would be around .020. A 5/8" split ring fit over the threads. Flat grinding on the sander finally brought it down to just the right fit where it locked down tight and lined up when turned with pliers.
Thought I had it! But, after getting home, I found that there was still lateral movement in the threads and some pressure would still cause it to move side to side.
Back to two wraps of teflon thread tape, which will do for today's test firing.
When I take that apart to clean again, I intend to coat the threads on the cap with blue Locktite and let dry then work it in until it threads tightly. I don't want it permanently locked on as it has to come off for internal cleaning now and then (back to the discovery of a copper residue build up on the inside).
I am looking for the correct size copper washer or crush ring to use as a spacer as the steel snap ring does not compress enough to allow tightly torquing it down.

Despite machining the cap end to the point where we know it is true and on center, the play in the threads means it could actually end up slightly off center on the brake. That would certainly lead to one side being smaller as the bullet passes through, as evidenced by the copper residue accumulation that was already present on one side of it when we reamed it out. The bullet could actually be scraping metal on the cap on the way out! That would certainly account for the random flyers these guns seem to throw. I was writing that off to milsurp ammo but now attribute it to the cap problem. The flyers are evident in both guns and the milspec one has not had the cap taken off yet.
While they both shoot extremely acceptable groups, on the whole, there are always the ever present flyers that throw off by a foot or more! This only becomes evident at 200yds or more where any variance in MOA is quickly apparent.

Repairing a loose fitting original cap could come down to filling the threads with weld and machining new, tighter fitting, threads. The difficulty would be in finding the correct metric die and centering it.
Only a good machinist would be able to mill out a brand new one from scratch! That's not me!
 

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Discussion Starter #18
Back to the drawing board!

Chalk that attempt up as a failure!
Enlightening and revealing for a few factors but a failure when the spacer ring blew out.

What appeared as a dead calm at home turned out to be 5-10mph wind blowing straight out from behind at the range. I already mentioned that wind plays hell with 8mm and any wind on this range is totally squirrelly
as it is unpredictable at different distances. It tends to downdraft when coming from behind and can cause a considerable drop. It also swirls at 200 yds when it deflects off the berm and comes back.

First shots right out of the case were expectations of great results.
I loaded it up and set it up on the bipod and monopod. Steady as an artillery piece. I set the scope to the hash marks previously penned for 240 yds. We threw a half dozen clays on the berm and set the targets at 200 yds.
First shot ... dead on, busted clay
Second shot ... dead on, busted clay
From there on in it was downhill all the way.

Wind was increasing and elevation dropping. Slight left/right variable depending on the gusts but not bad. I was missing low but hitting the same hole with the miss.
Meanwhile, son is shooting balloons and milk jugs with the milspec Hakim with open sights. He was doing really well but having the same elevation drops with the wind. Lapping the front of the cap on that one seems to have made it better.

I shifted to a 100yd target to see if I could get a group. Elevation and windage were way off with the wind and distance change. I missed my aim point but had several shots hit the same spot for a double hole.

Going back over things, I looked at the front and saw the spacer shim all distorted and blown out on one side. The cap was still tight but likely off center. This was a hard steel shim and enough force to distort it and blow it out says there is a lot of gas pressure coming out the vent slots.

I removed the muzzle brake cap and shot without it.
Recoil increased to levels comparable to a K98. I had to break out the shoulder pad and it was jumping on the bench with each shot.

Wind kept increasing and the few other long distance shooters there were having the same problems. It became pointless.

Conclusions:
With continued work, I do think 1" groups at 100 and 3" groups at 200 are possible. Steps to date have shrunk overall group size.
I was missing but hitting the same holes with the miss.
Out of the case zero was dead on to start with so it has the potential to be always on the mark cold out of the case.
I need to come up with a new plan for the muzzle brake cap.
Got to thunk on that a while.

Iron sights on the milspec are still damned good. Son killed quite a few balloons and milk jugs at 200 yds.
 

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4,850 Posts
Discussion Starter #19
Hakim trigger group screws and torque

While I have been fixated on the muzzle brake cap issue, there is another important accuracy issue with this rifle that I have noticed.
The receiver and trigger group are held in place with only three small screws. The free floating barrel design, while very advanced technology for the year of design, means the receiver and trigger group only mate and hold together in the stock on a very small amount of wood front and rear. The open middle is nothing more than a simple steel pillar bushing.

On the sniper version, Bubba took off the spring wire locks for the screws. The milspec still has them intact.
Without the wires, the screws will loosen by a half to full turn after ten rounds and get real sloppy with more rounds if not tightened.
Temperature, as the receiver heats up from firing, produces some looseness even in the milspec where, if you lift up the wires, the screws are somewhat loose when she heats up.
There is considerable play in the receiver and the trigger group when they get cooking at 100 rounds.

Point of impact does change when things get loose!
This definitely appears to be a contributing factor to accuracy increasingly noticeable as it heats up.

The bedding job is still on the agenda soon but I have yet to settle on method. It will be with Devcon 10110 but how much wood to take out and how to deal with the front and rear bolt holes still up for debate.
More importantly, the issue of the screws and even torque is becoming an item for consideration.
As I will have to find substitute bolts for posts during the bedding job, I will be looking for some type of hex head that would be an appropriate fix and replacement. Final assembly using a torque wrench to tighten each one to a set torque may be in order. Even torque, and keeping it there, may play an important role in accuracy.

Until I satisfactorily resolve this and find a solution, I suggest tightening the screws every twenty rounds when shooting even if you do have the wire spring locks on them.
 

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Discussion Starter #20
Keyholes - Is it you, the gun or the ammo?

Keyholes

Is it the gun, the ammo or you?

The quest for accuracy with the Hakim has lead me through much research on subjects like barrel crowning and lapping to bedding and stock mounting. Some of this has jogged a few memories from back in the days I was a firearms instructor and competition shooter.

Your group sucks, but why?
Is it the gun, the ammo or you? Here is a quick test to make that determination.

We often chalk off a bad day at the range to wind, temperature, something we did, whatever.
It just wasn’t a good day and we chuck our targets and go home disappointed. Other than the obvious, like twenty mile an hour wind gusts, we usually just dismiss it as one of those days when you can’t shoot for crap. Instead, what we need to be doing is bringing those targets home for a careful review the next day.

In the case of the “extreme Hakim” I am futzing with, I did just that and identified mechanical problems I am still working to correct. Yes, the damned “flyers” did exhibit evidence of Keyhole effect from yawing bullets.

Keyhole: definition
A bullet is cylindrical. The base of the bullet is flat. Holes left in your target by the bullet should be cylindrical. Holes that are not perfectly symmetrical and cylindrical are caused by bullets that yaw, tumble, or wobble during their flight to the target. Bullets that do not stay true to their spiral during flight end up off target due to wind resistance.
A “Keyhole” in your target is an indication of a bullet that wobbled during flight and passed through the target on an angle. Depending how grossly the bullet was spinning off center, the hole in the target can be oblong, distorted, depressed or actually have a circle with one flat edge that looks like a Keyhole, where the flat bottom edge of the bullet cuts a straight line as the bullet passes through sideways.

This is much more visible and easy to identify with .38 wad cutters as these flat faced bullets were designed to punch a clean and uniform hole in the paper making them easy to see. It is more difficult to observe with pointed bullets where closer examination of the holes is in order.

The test:

In order to correctly analyze this, first you have to shoot some groups and save the targets.
Most of us shoot a crap group, attribute the problem to something we did and throw the target away without closely inspecting it. Ok, it has a bunch of off the mark flyers … so, was it trigger mash, grip and stance, ammo, the gun? How to determine which and correct it?

First off, shoot at distance! This is not going to show up by shooting a rifle at fifty yards!
You need a good 150-200 yds so the group spread really shows the misses.
Bring the targets home for later when you have time to closely inspect them.
Set them up in good light against a light background where you can clearly see the holes.
Pick out the bulk of your overall satisfactory group, the majority of on target hits, and draw a circle around it.

First, we are going to examine the holes outside that circle. These are most likely the “flyers” caused by one of the above factors. They are the ones most likely to exhibit Keyhole effects if that is indeed the problem.

Find a ball point pen, wooden dowel or other round object that is approximately the same size as your bullet. The correct size tool will fit snugly into your barrel.
Insert this “pointer” into your hole being careful to insert at a 90 degree angle so as not to distort the hole.
Closely compare the hole to the roundness of your pointer. The hole should be perfectly round and symmetrical compared to the diameter of your pen or dowel. If the hole appears oblong, torn on one side, flat on one side, or otherwise not perfectly round, circle it with the pen. We will go back and look at it again later.
Repeat with all the holes outside your circle carefully marking all that appear this way.
Move to the inside of the circle and check the holes inside it. Mark any that appear out of round.
The holes inside the circle may require much closer inspection to determine if they are not perfectly round as these will be the ones with the least yaw and wobble.

Now, back up a few feet and look at the target and the holes you have marked.
If you see a percentage of marked holes, especially outside the circle, you have a Keyhole problem!

The subtle signs of Keyhole

Now that you have circled the obvious holes, it is time to take a much closer look.
A magnifying glass may be in order.
Gross Keyholes are easy to spot as one side of the hole will have a section of straight edge, where the base of the bullet cut a straight line indicating it passed through sideways or grossly off center.
Less distinct Keyholes will be slightly oblong. Missing a distinct straight line, look closely for holes elongated on one side as compared to your tool.
The hole may appear round but looks dented in one area. The paper may look like it was pulled down and through as opposed to cleanly cut. Look at the reverse side to see if the cardboard looks compressed on one side. Do other suspect holes have a similar pattern?
Sometimes you can place the target a few inches away from a background, like a light wall or paper, and shine a flashlight through the holes from the front. The projected holes are easy to see and you can detect any oblong abnormalities.

If you need to have some examples to compare with, take your pen and push it through the target at various angles to leave such distorted holes until you get a grasp of what you are looking for.

If you are seeing a percentage of these suspect holes and, when compared against the larger percentage of “good” holes in the bulk of your “good” group, you have a problem!

Is it YOU?

We all have our faults which is why we practice. Flinch, trigger mash, bad grip and stance … we all do it at some point in time. These are shooter induced problems we work hard to correct. It sometimes requires a trained observer with a keen eye to catch these little mistakes and point them out as the shooter often does them unconsciously and never realizes what they are doing.
Even as a trained instructor and shooter, I still often catch myself flinching or trigger mashing.

The Keyhole examination of the target will point this out. Misses that have perfectly round and symmetrical holes can then be attributed to wind, ammo or something the shooter is doing. They are not a mechanical problem. The perfectly round “flyer” is a “you done it” and a round you threw with flinch or mash.

Is it the GUN?

Do a little reading on barrel crowning and lapping. At the point where the bullet leaves the lands and grooves of the barrel, there is considerable gas pressure behind it. At that exact point, if anything is even slightly out of round, there will be more gas pressure against the base of the bullet on one side or the other. This pressure differential pushes the base of the bullet off center causing yaw. The bullet will continue to spiral but the base will yaw off center in an arc. Air resistance during bullet flight against this yaw and wobble will cause the bullet to change course in unpredictable ways. This bullet will end up as a “flyer” and often wildly off target depending on how bad the yaw induced.

If a large percentage of your “flyers” exhibit Keyhole signs, it points to a mechanical problem with the gun.
Most often, the barrel crown is out of round. Dented, nicked, scratched, dropped and bent, for whatever reason, your crown is damaged and needs attention. This can be a simple fix, as in lapping it with a lapping tool and grinding compound or require a major fix like having it re-crowned depending how bad the damage is. Lapping usually clears up minor problems and shrinks group size. Closely examine the crown with a magnifying lens, a strong light, and your pointer tool to compare symmetrical roundness. Look for even the smallest dent or gouge.

An extremely dirty bore can distort the bullet. Accumulated build up of lead and copper residue in the grooves can squeeze the bullet causing it to distort as it travels down the bore. It can get compressed off center and cause a bulge or uneven hump in the jacket when the lead is compressed and has nowhere to go. Distorted bullets don’t fly straight!
Extensive and thorough cleaning is in order. Clean and brush thoroughly, clean again, and then clean again until the bore is shiny clean with distinct crisp rifling. Patches should come out clean with no copper residue. You may want to try different cleaning methods with different products and even copper removers until you are sure the barrel is as clean as it can get.
Compare groups and holes after such a cleaning and see if the problem goes away.
If not, we are down to ammo or the bore is shot out.

Is it the AMMO?

Burning ammo to compare performance differences gets expensive!
You have to pump 20-50 rounds into a target to get a representative group to examine.
It is widely accepted that Milsurp ammo is crap that was mass produced for volume and not to the exacting standards of modern factory ammo. However, burning cheap Milsurp until you have eliminated all other potential causes would be the recommended route until you are sure there is little else left to try. Once you reach that point, a trial of several boxes of different factory grade ammo is the last remaining test. Once again, if you are showing signs of a keyhole problem with factory grade ammo, go back and look for a mechanical problem with the gun.

Stop wasting time, energy and ammunition!

If your groups suck and every time you go to the range you are having consistently bad results, take the time to perform the test! Determine if it is you, the gun or the ammo.
If you can spot and fix the problem, your next trip may result in a much tighter group and more pleasing results. A $6.95 lapping tool and a tube of valve grinding compound may be the cure for the gun you are about to give up on! You don’t want to “dump” or get rid of a gun that may, in fact, be easily salvaged just because you can’t shoot worth a damn with it until you have completely analyzed the problem.
 
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