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Discussion Starter · #1 ·
The M39 Project Tutorial

’67 M39 Custom stock, pillar post bedding, recoil suppression, Huber trigger, bolt and sear tuning, bore conditioning, scope mounting.
Full detailed step by step instructions.

The custom M39 project nears completion and as the weather improves, I have had the chance to test drive her enough to be satisfied with the results. It has a good 300 rounds or more through the bore now. Still waiting on the X-Caliber bipod, due to go into production any time now.
Bolt is on the way to Charity Littleton http://www.boltcheckering.com/ for a little dress up. Extra panels to be added on the flats on the top as well. Thinking about having the stock done eventually http://www.checkering.com/.

While I have not drilled a hole through a quarter at 200 yds with it yet, too much wind and being unable to hold it steady enough on a sandbag rest without that bipod, it has shown that it can and will do that. I have not touched the adjustments on the scope since I got it zeroed. Cold out of the case, it will reliably nail a golf ball at 250yds, first time, every time. Zero has not changed even a hair. I have seriously taken up golf, chip and putt at 250 yards, bouncing golf balls around on the berm until there is nothing left of them.
BTW: That’s with milsurp Polish 7.62x54R, the last cheap case I bought. One of the guys on the range says he can hand stuff some really accurate 54R. That I have to try!

Yes, I do admit to spending entirely too much money on this project, especially when the machinist ripped me on the scope mount, but it is still cheaper than any new production “sniper” with accessories you can buy. Satisfaction from building this “toy” has proved worth the time, money and effort!

Bear with me on the remainder of the tutorial as I am behind on the pictures and text and have some catching up to finish it.

pics: right side, left side, scope mount.
Playing card 200 yds, 1 shot 8-10 mph wind
Golf ball 250yds, 5 holes 8-10mph winds
Group 2/11 20 mph winds
Group 12/3 15mph winds
 

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Discussion Starter · #2 ·
Disclaimer for “Purists”.
My name is not Bubba nor am I descended from any of his clan or gene pool.
I am a serious collector of vintage milsurps.
I do like to tinker and invest a lot of time, labor, and money in the tools and parts for the “project guns” which I find as satisfying and entertaining to build as shooting them. This is a “hobby” on which I enjoy investing considerable time and money.
These projects are not for those who are not slightly mechanically inclined or have difficulty operating a screw driver.

Previous exploits:
http://forums.gunboards.com/showthread.php?p=282054&posted=1#post282054
Dressing up an M44
http://forums.gunboards.com/showthread.php?t=21165
Bedding a Hakim
http://forums.gunboards.com/showthread.php?t=36415
Smoothing out a Mosin bolt

Why customize an M39?
Looking for a rugged and accurate rifle that shoots the cheapest milsurp ammo currently available for training purposes, as I am a firearms instructor http://sepulvedainc.com/ and http://www.shootnj.com/instruct.html, I got hot to trot over the Finn M39. Mosin rugged and able to stand up to much abuse, the fully adjustable high quality sights make it perfectly suited for the job. The Finn is just a much better Mosin!

I purchased a 1970, “unissued” “new bore”, or so it was advertised. There is conjecture over ’67-’73 rifles being made for “officer and sniper training” with superior imported Belgian barrels and hand tuning. You can either believe that or fight about it, I can only attest that the 1970 had a bore so clean it looked like it just came from the factory and the bolt and trigger had received some very good TLC from someone who knew what they were doing! It has proven to be one of the most accurate bolt rifles we own and in no way compares to your average Mosin of any type!
The ’70 now ranks as one of our favorite 7.62x54R rifles!

I get a kick out of plinking with my Hakim sniper. Shooting small objects at distances longer than possible with iron sights and the naked eye is most entertaining. A year long process of building and correcting the Hakim yielded valuable experience. 8mm is scarce and expensive these days and I just can’t afford to shoot it like I used to. I had need of something that good to shoot 7.62x54R at small targets and long distance.
There are simply limited options available. While I have some very nice Mosins, they are no equal of the M39. Finding a good bore on one that isn’t “collectible” or otherwise too nice to customize is a crapshoot with limited odds. I long held intentions of making a custom long range bench shooter out of an M91 but, after considerable searching, I was never able to find the right one for the purpose. The long barrel M91 would be a good foundation but all are either too good to scrap or too worn to use.

I bought another Finn M39, this one a 1967, again “unissued” “new bore”, or so advertised specifically for the project and with all intent to customize it.
The price was acceptable as a starting foundation for the project at $325.00.
The ’67, as received, proved to be just as accurate and “mint” as the ’70 except for the trigger and bolt which were not hand tweaked to perfection. Following a Huber trigger and a bit of work on the bolt, the ’67 proved comparable to or better than the ’70.
The bore was perfectly clean and pristine new looking after removing the cosmoline.
So… here is a fancy Mosin, with a virtually new bore, at a reasonable price and it shoots the ammo I most often use. Good place to start!

pic: 1970 M39
 

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Discussion Starter · #3 · (Edited)
THE STOCK

The original military stock is simply too heavy and too much wood, besides, retaining the original unaltered stock and hardware means it can be returned to it at any time in the future.
Unfortunately, custom Mosin stocks are hard to come by.
No one, other than Boyd’s, is currently turning out any wood stocks for Mosin.
Synthetics are not only ugly, they are hollow and not suited for bedding or recoil suppression.

http://www.boydsgunstocks.com/Replacement-Stocks-for-Mosin-Nagant-s/68.htm
This Monte Carlo style is the only Mosin stock they make.
I asked them about inletting one of the other custom stocks they make for a Mosin and they won’t do it.
This stock is always listed as “Out of Stock” on their site but make a phone call and they will tell you to what dealer the last order was shipped.
I found mine at http://www.dmfirearms.com/index.php...ucts_id=1072&zenid=bq2q3a29io74u5bujg6oitr021
a large order he had waited months for and the second one was one of the last remaining.

I do so want one of these M28-76 stocks!
But alas, until I can get my hands on one, the Boyd’s will have to do!
 

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Discussion Starter · #4 ·
BEGIN FITTING

As experienced with the Boyd’s stock for the M44, rough inletting, listed as 90% is more like 70% and will require removing quite a bit of wood just to mount the action.
As the rear sight mount on the M39 is substantially larger than found on an M44, it is necessary to take out a considerable amount of wood to accommodate it.
Considering the volume of wood that has to be removed in this area, and the impossible chore of correctly matching the area of this rear sight mounting, it will be necessary to bed the area of the rear sight with epoxy all the way to the front of it rather than free floating the barrel from the end of the receiver forward.
Pic 1

Start by marking the end of the sight mount and removing wood from the front lug forward to that point with the Dremel 5/8” drum sander.

The rear section is going to be bedded and will provide the support for the receiver in step #2 of the bedding process. It is necessary to remove wood along the sides of the receiver to provide the necessary 3-5mm space that will be filled with epoxy. (*see notes on Devcon steel epoxy)

At this point, we are looking to create a 3-5mm void for the rounded part of the receiver to be filled with epoxy letting the action mate with the trigger group and torque up against the wood around the screw holes. That process will be reversed once the top layer of epoxy is cured and supports the receiver when we will inlet and bed the bottom areas surrounding the screw holes.
Pic 2
 

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Discussion Starter · #5 ·
Bore out screw holes

Careful inspection of the Boyd’s stocks, in both cases, revealed that the screw holes were not only off center but off angle as well. Their jig must be off by a considerable amount. Both stocks proved problematic in getting the screws to pass and align with the threads.
The holes have to be bored out to 3/8” or more anyway for the steel pillars so go ahead and ream them out with a 3/8” drill bit and slightly oversize them to leave plenty of slack for the pillars and adjusting angle on the screws.
*skip down the section on making the Pillars, make and rough them out and then come back.
The action can now be mounted on the stock. It may seem a little sloppy at this point, as it should, which will allow it to be correctly positioned for the top layer of epoxy. That support layer will determine the fit of the action to the stock for all future steps and allow you to correctly align the barrel with the stock as, with the rough inletting being out of alignment to begin with, the action will not align correctly without considerable free play.
Fit the action to the stock with pillars in place and bolt it in.

On this particular stock, I found the depth of the receiver to be a bit too low, especially in the rear tang area. It would warp the receiver and cause the bolt to bind and the sear not engage properly. It was necessary to use the shims from the original stock underneath to position it at the correct height. The action can now be firmly seated in the stock and tightened down.
Check for proper alignment of the barrel and make sure it centers correctly in the front groove.
NOTE: You can warp the receiver if the correct height for front lug and rear tang are not correct and when the rear screw is tightened down, it can pull the rear of the receiver down enough to cause bolt cycling issues. Be careful to maintain correct alignment and do not torque the rear tang down to maximum until you bed that portion. Use shims if necessary.
 

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Discussion Starter · #6 ·
Fill slot with wood filler

The slot in the front portion of the stock extends over half way under the area of the front sight mount which will be epoxy bedded. This would require a large volume of epoxy and needs an effective dike to shape it at the front of the mount.
Devcon can be sanded to shape but, it is extremely hard and would require much more work to shape in the forward section where the barrel is free floated as well as adding considerable weight.

To fill this void, I chose Elmer’s Epoxy based Wood Filler putty. Standard wood filler will never dry completely with this thickness. I have found the epoxy based (2 part mix) filler very easy to work with. It sets completely hard and cured all the way through in about four hours. It is easily sanded and quite solid as well as being very light.
Fill the void with epoxy filler and let cure.
 

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Discussion Starter · #7 ·
The front area of the stock where the barrel will be free floating and have no contact needs to be enlarged anyway. The easiest way to accomplish this is sanding it out with a ¾” pipe wrapped in sand paper after roughly removing some of the wood with the Dremel sanding drum.
This just happens to provide the right amount of clearance under the front portion of the barrel to free float it. You should end up with a uniform 2mm of open space around the barrel in this area.
 

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Discussion Starter · #8 ·
Next, we are going to create the 5mm depth for the Devcon under the sight base.
With the action firmly screwed into place, mark a line on the side of the receiver and rear sight base with a pencil where it meets the stock for a reference point. Remove the action.
Measure the distance to the bottom of the sight base which should be 14mm.
Add 5mm to that for the Devcon epoxy and you need to remove wood to a depth of 19mm under the front sight base.
Pic: measure depth

Remove wood with the Dremel drum sander from the front lug hole forward to the front end of the sight base to this depth and leave a 3mm clearance on the sides.
The finished and sanded front portion should now resemble this
Pic: wood removed

Note the small groove in the wood filler and down each side of the stock.
This is cut about 1/32” deep using a small cutter head on the Dremel.
The grooves provide a rough surface and an undercut for the Devcon to “lock” into the wood.
Even though the Devcon adheres very strongly to bare wood, these undercut grooves provide a slot for it to form a tab that will prevent it from coming out of the wood even if the other surface contact areas should separate.
On the M44 stock, there is no evidence of the Devcon epoxy working loose from the wood after hundreds of rounds but, this is 7.62x54R which pounds it like a hammer with every shot. The slots and grooves just provide extra insurance that it can’t come loose.
 

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Discussion Starter · #9 ·
Open up trigger group

At this point, you should be able to mate the receiver and trigger group to the stock and tighten up the screws. On this particular stock, I found the rough inletting to be considerably off, along with the screw holes. The trigger group and magazine fit very tightly and were binding in several spots. Alignment was off enough to warp the receiver and barrel out of correct alignment in the center of the stock. The barrel ended up slightly canted to the right.
This area will be epoxy bedded anyway! Go ahead and remove wood in this area by using the full 5/8” width of the Dremel sanding drum.
Pic: sand trigger group slot

From the top, open up the magazine well in a similar manner
pic: open up well from top
 

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Discussion Starter · #10 ·
Assemble and check

With the action firmly mated in the stock and screwed tight, the only areas of contact with the wood of the stock should be the bottom of the front lug and rear tang. All other areas should have a good 3mm free space surrounding them. The barrel should correctly center in the front of the stock with 1-2mm free space under the free floating portion of the barrel.
Nothing should be tight or binding. The bolt should work freely and trigger and sear should operate properly.
We are now ready for the first application of Devcon and the top bedding layer.
Remember that this first layer will determine the correct alignment of the action and barrel in the stock in the next step when wood is removed from the lug and tang area so correct fit and alignment is critical at this point!

REVIEW NOTES ON DEVCON

Before we begin the bedding process, let’s review some of the things we have found out about Devcon epoxy.

Devcon 10110 Plastic Steel Putty
http://www.devcon.com/devconfamilyproduct.cfm?familyid=101&sr=1

Web research reveals Devcon 10110 appears to be the epoxy of choice for bedding projects.
It is a non-shrink finished product that will completely fill voids without changing size as it cures.
It can be sanded, drilled, machined or otherwise worked in a finished and cured state.
Devcon is one of the strongest epoxy products.
It adheres extremely well to any surface it is applied to with a very strong bond, particularly on wood.
It also adheres extremely well to itself, meaning additional layers that may need to be applied will bond with an already hardened area that will not separate from itself. Any remaining voids can easily be filled with additional applications.

Working with Devcon

The epoxy is mixed 1/3 hardener to 2/3 base. It must be stirred and kneaded continuously for five minutes until thoroughly blended to a uniform color and consistency.
The fresh mixed epoxy is a little soupy. It will run or settle with gravity at this stage.
This is good to fill small areas or smear a base coat over a wood surface. Use the thin mixture to lightly coat wood where more will be needed later, spread around until sticking to the wood in all areas and work out any air pockets. (Note: large areas of epoxy will trap air bubbles. It is important to “work” these areas and probe with a toothpick to expel any trapped air bubbles)
To fill larger voids, let the mix stand for approximately 25 minutes when it will begin to set up and get gradually stiffer. You have about 30 minutes to work with it at this stage where it is more like a putty and will stand and hold shape where applied. It is still easily compressible to final shape and fitting and will flow into voids. It becomes too stiff to work after one hour from initial mixing.

Mix the base and hardener on a plastic plate with a plastic knife. Once mixed, place a small dot off to one side and stick a toothpick into it to monitor stiffness. This control can be used to monitor how hardening is progressing and gauge the correct timing to apply and work with it.

Excess epoxy that squeezes out when compressed can easily be scraped off to remove once it starts to set up. White Vinegar is the solvent to remove any excess that ends up where you don’t want it. Wet a paper towel with straight white vinegar and use to wipe excess off metal parts and wood. It is easier to let excess stand until it is fairly stiff and trim with an exacto knife than trying to wipe off fresh and thin epoxy with vinegar.

Kiwi neutral shoe polish is used as the RELEASE AGENT to keep Devcon from adhering anywhere you don’t want it to stick. Wipe a layer of Kiwi on any metal parts to keep the epoxy from bonding to it. Let dry to a white film and apply two additional coats letting each one dry.
You can apply wet Kiwi to any area you suddenly realized you missed and it will still work.
Be sure to apply a good layer to any SCREWS and THREADS where epoxy may squeeze into them to ensure you don’t firmly epoxy the screws into the holes. Devcon will lock threads as solidly as Locktite!

Plumbers Putty will work as a suitable dike and filler to prevent epoxy going into any voids or areas where you don’t want it. The epoxy will not squeeze into these filled areas and will not stick to the putty allowing you to easily remove any excess later. You may also use modeling clay.

Devcon requires 3-5mm thickness to be effective!
For any areas that will be filled with epoxy, remove at least the necessary 3mm of clearance to fill with a layer of epoxy and, wherever possible, remove a full 5mm or more.

Timing is everything when working with this epoxy!
Allow yourself at least eight hours to complete each application to be sure you can get back to your work before a final set takes place.
In the first hour, you will mix and apply the epoxy choosing when to use a thin and runny application working up to filling voids with a thicker putty like application.
At two hours, the epoxy takes on a firm set and will hold shape but isn’t cured yet.
At this point, loosen all screws to be sure you can break them free. You can tighten them up again once sure they are not stuck. You can also easily scrape off and trim any excess from places where it does not belong. A razor blade or Exacto knife will slice through any protruding epoxy you wish to remove. This is a good time to trim and smooth any exposed edges.
*Although some people recommend leaving the work assembled for three days, Devcon instructions state a functional 75% cure is achieved in sixteen hours. It is hard enough to separate the parts and hold shape in four hours. An additional application to fill voids can be applied after four hours as needed. At 4 hours, the epoxy is stiff enough to hold shape but still somewhat malleable. Torquing down the screws is sufficient to “push” any that is creating a high spot or out of place into a final set. Once you have trimmed off any excess, assemble everything and torque down the screws as tight as they will go. For the purpose of working in phases, let each stage cure for two days before moving to the next.
*Additional hardener above the recommended 2:1 ration will increase the set speed of the epoxy. Do so at your own risk to speed up the process as slight increases will rapidly speed up hardening.
*The chemical reaction of hardening is temperature dependent. The higher the temperature, the faster it sets. The process can be speeded up by placing it over a heater vent.

Fill voids with a second application.
Your first application mold may come out with some voids that need additional epoxy.
Expect your first “casting” to have many such voids, especially in areas where a large quantity is applied.
After it has set for four to eight hours, rough up the surface a little with coarse sandpaper, wipe off dust with an alcohol wipe (which also removes the Kiwi), and apply a second layer. Be sure to apply another fresh layer of Kiwi to any metal parts.
Correct application of subsequent layers should have enough that excess squeezes out when assembled and screwed tightly into place.

**SPECIAL NOTE ON DEVCON – FREEZE IT!!!

Don’t know why this thought didn’t come to me earlier!
Of course, it came too late in the process to use except for the last steps after going through numerous batches of mixed epoxy and discarding the excess.
FREEZE your leftovers!
I had a good 1oz of excess epoxy mix leftover from one of the last batches. As I was applying it to a large area and expected to have a few voids left. I anticipated having to mix another small batch for subsequent filler. Out of curiosity, I stuck the plate with the leftover into my -40 degree deep freezer.
While I was speeding up the curing process of the first application by letting the stock sit over the heater vent (reduces curing time by about half), the leftover froze solid in the deep freeze.

I was rather amazed to pull it out over six hours later to find that it thawed out to just mixed consistency in a few minutes as it reached room temperature! The chemical reaction of the hardener appeared to have been stopped dead in its tracks!

That particular mold turned out perfect without the need for any additional filler so I stuck the plate back in the freezer.
THREE DAYS LATER …
Having totally forgotten about the plate in the freezer, I found it and pulled it out.
It appeared to be solid but thawed within a few minutes and was STILL quite near just mixed consistency!
A small sample on a toothpick was taken and allowed to harden normally. It set up and hardened on schedule.

Don’t take this as gospel … I have received a reply from Devcon on a technical inquiry about this. Or course, they do not recommend this although they do verify it as true. Hardening requires the heat released by the chemical reaction and freezing will halt the reaction. For future projects, I have mixed a large batch and shaping the excess into a log roll on a plastic plate, cutting off what I need and freezing the rest to remove additional applications in chunks to thaw out and use later!
It certainly saves a lot of waste material and mixing time!
*Three weeks in the freezer and still good!
*Note: For this project, the Devcon will be mixed in large batches and frozen.
 

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Discussion Starter · #11 ·
STEEL PILLAR POSTS

The purpose of steel pillar post bedding is to provide a steel sleeve for the screws to pass through.
Being steel, they can not compress or expand with changes in moisture in the wood.
The distance between the trigger group and the receiver, at the mounting points, becomes fixed.
Screws can be torqued down to maximum tightness and will not loosen and there is no way this can compress or damage the wood.
While you can skip the steel pillars and encase the screws in epoxy, there are the additional problems of epoxy sticking to screws or threads, which could prove fatal to your project.
It is much simpler and more effective to use the steel pillars and anchor them firmly into your casting. Properly done, no epoxy gets on the screws or threads and there is just enough slack space to ensure they will pass through and mate with the threads.
pic: steel pillar posts

The next chore in order was making the steel pillar posts.
The front post is 17mm long and the rear 35mm long.
(This is measured by inserting the caliper post through the hole until it contacts the trigger group and then crank down the caliper until it rests against wood from the top. You can oversize the exact length by 1mm and then grind down the pillar if it is slightly long.)
When I did this for the Hakim http://forums.gunboards.com/showthread.php?t=21165
I was fortunate enough to find 3/8” steel sleeves at the hardware store that actually fit the screws.
No such luck this time, the 7mm Mosin bolts are just a tad too big to fit through nor could I find one 35mm long!
Spent the afternoon in the machine shop where we crafted the 35mm from a 3/8” bolt shank cut on the lathe and bored out. We then we cut a 17mm from a 3/8” sleeve that had to be bored out. Took a bit of doing but we ended up with the correct pillar posts.
The holes in the wood need to be drilled out to 3/8” and reamed a bit to get the screws to pass through and hit the threads. The pillar post sleeves can be a bit loose in the hole through the wood as the epoxy will hold them firmly in place once the wood is removed from the top and bottom. If, you have access to a good metal lathe, making them from scratch is the easiest way to go as there is no available steel sleeve that correctly fits. Even with good machining, it still required a little grinding with the Dremel to get them just right and properly aligned with the screws.
*Note: on a subsequent bedding project, my machinist just happened to have a length of 3/8” stainless steel aircraft hydraulic tubing that proved to be perfect for these projects with an inner diameter just right for Mosin screws. I scrounged a length from him. It can be cut to length with a pipe cutter very precisely.
*Pay attention the ANGLE of the pillar and screw for the rear tang as it is necessary to bevel the ends of the pillar to match so they are flush.

Oversize the holes through the wood until the pillars pass through easily. You want enough slack in the pillars so that the screws can easily be aligned in the threads and centered inside the pillars without cross threading or resistance.
Assemble and make sure the screws line up correctly with the threads and tighten down.
Check the correct height of the receiver, with the trigger group flush on the bottom of the stock.
If you have to grind a little off the pillars to lower it, do this now until you have correct alignment.
The fit of the pillar through the hole in the wood should be a bit sloppy and have plenty of play.
We will coat the pillars with epoxy anyway in the next stage when they will become firmly anchored and married to the wood in final position.
Rough up the exterior surface of the pillars with a coarse file creating a rough surface for the epoxy to adhere to. Clean off with alcohol. Swab the inside with Kiwi on a Q-Tip.
 

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Discussion Starter · #12 ·
TOP LAYER EPOXY

As previously stated, the top layer is absolutely critical as it will determine the position of the receiver, barrel and trigger group from here on out.
It is absolutely essential to make sure that both the receiver and the trigger group line up in the correct position and height where you want them in the finished stock.
As the receiver, at this point, is resting only on the front lug and rear tang areas, there is some ability to shim it back and forth with the screws slightly loose.
Check and double check this alignment. Place reference marks with a pencil at the front of the stock to center the barrel and down the sides of the receiver to verify the correct height.

MASK off any areas you don’t want epoxy sticking to with painter’s masking tape. Coat the exposed tape with Kiwi to keep epoxy from adhering to it.
DIKE the front lug and rear tang area with putty.
Assemble the action and screw tight.
Disassemble and remove any putty that spread or pushed out.
The objective, at this point, is to epoxy cast ONLY the rounded top area where the receiver mates with wood. The front lug and tang area, as well as the flat bottom, will be cast in the next step. We DON’T want epoxy getting into those areas at this time or sticking to wood that will be removed in the next step.
DIKE the area between the front sight base sides and barrel with as much putty as you can work into it. Epoxy will force its way into this area causing real problems removing the action later!

Prepare the wood by blowing out and scraping loose any sawdust from sanding. Pay particular attention to angles and crevices where sawdust will stick. Dig it our with a pick if necessary.
Wipe down with denatured alcohol to remove any final dust layer that could prevent the epoxy from sticking, let dry.
Pic: dike & mask
Pic: dike trigger
Pic: mask top
Pic: dike sight base
 

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Discussion Starter · #13 ·
Mix your first batch of epoxy per above instructions.
Apply the epoxy, liberally, to the wood and work it around ensuring that there are no air bubbles and that it has coated and adhered to all areas of the wood.
I prefer a plastic knife as you can get a whole pack of plastic utensils and throw them out as necessary. Probe any deep areas with a toothpick to expel any trapped air bubbles.
Be sure to “work” the epoxy against the wood in all areas to make sure it is adhering.
You have a good thirty minutes or more to work this application of epoxy into place trying to estimate and fill the required 3-5 mm voids. More is better, excess will squeeze out.
Drop in the receiver being careful to keep it relatively parallel to the stock so as not to squeeze out too much on one end or the other as it settles in place.
Press down firmly until seated. Some excess epoxy may squeeze out. Don’t worry about that, we will remove it in a few hours by slicing off with the Exacto knife.

CHECK THE SCREW HOLES through the pillars.
Some epoxy may have squeezed into the pillars when seating the receiver.
Dig this out with a toothpick.
Drop your screws through the cleaned out pillars but don’t tighten.
Remove the screws and wipe off any epoxy that got on them.
Repeat until you can put the screws through the pillars and remove them with no epoxy on them.
Insert the trigger group and place the screws, making sure they engage the threads easily.
Tighten down slowly and lightly. Excess epoxy will squeeze out.

CHECK YOUR ALIGNMENT! This is the absolutely CRITICAL stage where you want to make sure that the action is properly centered and aligned in the stock and with the correct height, as measured against your pencil marks.
When this stage sets up and cures, the position is FINAL from here on out!
Once alignment is confirmed, tighten the screws down as tight as they will go.
(Note: If it wants to pull off to one side as you tighten the screws, it may be necessary to shim it into position and maintain the alignment with the shims as you tighten the screws)

Set the assembled gun in a level position.
It can be helpful at this point to gently tap the stock in several places with a rubber mallet to “settle” the rather loose epoxy which will flow into any voids.

Take your plate with the excess epoxy and stick it in a sandwich bag and place in the freezer.

Step away and leave it alone for 2 hours!
At the 2 hour interval, unscrew and remove the screws without moving the receiver or the trigger group to ensure you can remove them and they have no epoxy on them.
At 2 hours, even if a bit of epoxy got into the threads, it will break free easily. That is NOT the case once it sets for 4 hours! After 4 hours, epoxy on the threads will be a solid as red Loctite!
Examine and clean if necessary.
Replace the screws and tighten them down hard again.

Depending on TEMPERATURE, 4-6 hours is when you will have a rigid “set” and the epoxy will be hard enough to separate the parts. You should have your “test blob” or epoxy you set off to the side to evaluate hardness. Do not attempt to separate the parts until the test block is sufficiently hard and no longer tacky or you will destroy your mold. It is still quite malleable at this point.
Remove the screws.
TRIM OFF any excess epoxy that has squeezed out above the stock with an Exacto knife. It will slice off fairly easily at this point as the epoxy is firm but not completely hardened.
Turn the gun upside down.
The epoxy will have a rather firm grip at this point and it may seem the action is solidly frozen into the stock. It WILL break loose!
Using a rubber mallet, brace the stock across your knees, grasp the forestock firmly, and WHACK the barrel sharply downward with a rubber mallet. (May require several good whacks!)
It should break loose and come partially out of the stock.
Turn it back over with the action up and keep level.
WIGGLE the barrel up and down with short strokes until the tang area comes free.
Don’t try to lever it out from the front, using the barrel, or you may compress and damage the rear areas of epoxy.
Work it up and out slowly in incremental steps until it comes free.

You should now have a rather good mold of the front sight base and the rounded areas of the upper part of the receiver.
Expect a few voids where you didn’t apply enough epoxy or where it settled out.
Wipe off the surface of the epoxy with alcohol to remove any Kiwi.
Scrape off any excess epoxy that adhered to the receiver.
Trim off excess epoxy that squeezed out of the top of the stock.
Re-apply a coating of Kiwi to the receiver.

Pic: top casting 1
Pic: top casting 2
Pic: top casting 3
Pic: top casting 4
 

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Discussion Starter · #14 ·
Take your plate of excess epoxy, that you stuck in the freezer and let it thaw for 20 minutes or so, while doing the above.
Fill and smooth out any voids with a second layer. Small imperfections and voids are easily filled by placing a small amount of epoxy on the blade of an exacto knife and scraping flat over the area to be filled in.
Assemble as before. Check your screws in 2 hours once more.
Go to bed! Or, wait another 4 hours until it is firmly set once more before removing the action using the same method.

Upon completion of STAGE 1, you should now have a perfect casting of the front sight base and receiver up to the front lug, as well as the rounded sides all the way back to the rear tang.
If you have voids, you can repeat the process and fill them until you obtain this first stage casting to your satisfaction.

Note from the pictures that some epoxy has squeezed into the front lug recess and up into the rear sight base creating ridges on either side.
This can be cleaned up using the Dremel. Using the small cutter head, grind down until you can remove the putty and tape underneath. Leave behind only the rounded side areas that will support the receiver.
The ridges on the sides of the sight base can be sanded down almost flat using a small sanding block.

Pic: sand down ridges
 

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Discussion Starter · #15 ·
STAGE 2
Front Lug and Rear Tang

Remove the pillars.
Use the Dremel to remove any excess epoxy leaving only the rounded sides.
Remove any tape and putty.

The next task it to bore out the screw holes and remove wood from the flat bottom areas.
The area of the screw holes is the area that will support and anchor the pillars.
The front lug and rear tang are the areas that take the bulk of the recoil and need to be the strongest part of the mounting.
Place a straight edge across the top of the stock and use the post in the caliper to measure down inside the screw hole to a depth of 5mm. Place a mark inside the screw hole at this depth.
Turn the stock over and do the same from the bottom side.
Using a 5/8” wood boring bit, bore the screw holes out down to the level of your marks from both sides. You will now have a 5mm deep hole on each side of the stock with approximately 5mm of wood remaining in the middle to hold and support the pillars and marry them to the wood.

Pic: top casting 1
Pic: top casting 2
 

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Discussion Starter · #16 ·
Remove the flat wood in the middle behind the front lug hole to a depth of 5mm.
Use the Dremel cutter head to indent a groove under the side epoxy.
Remove wood to a depth of at least 5mm in the rear tang area, to the depth of the bored out hole.
Using the cutter head, create a 45 degree “wedge” area in the rear to create a tab on the epoxy cast around the rear tang undercutting the wood on top.
Pic: rear tang area 1
Pic: rear tang area 2

Remove wood to a depth of 5mm from the section in front of the trigger slot and make sure the recess for the spring screw is at least 3mm deeper than the screw.

Remove the magazine spring assembly from the action.
Remove the trigger but replace the spring and tighten the screw down.
DIKE this area with putty following the correct shape to create the recess for this area.
Dike the trigger slot with putty.
Pic: dike receiver
 

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Discussion Starter · #17 ·
Coat the inside of the pillars once more with Kiwi and wipe the exterior with alcohol.
Coat the screws well with Kiwi and work some into the threads.

Mix about 2oz of epoxy.
Coat the center of the pillars, in the area that will sit in the wood remaining in the holes, and push the pillars in place. Use a toothpick to push epoxy into the remaining voids around the pillars.

Coat the flat wood areas behind the front lug, rear tang, and under the trigger spring and screw.
Work epoxy down and around the pillars up to the top of the pillar.
NOTE: These areas will trap air bubbles! It is necessary to work the epoxy in these areas with the toothpick until the air bubbles are removed and you are sure the area is completely filled with epoxy.

Let your epoxy mix set up a bit stiffer for twenty minutes.
It will retain shape better when worked against the vertical side areas.
Use visual estimation to pack epoxy against the side areas until it looks like it will match up to the shape of the receiver.

Insert the receiver, keeping it level, and slowly press into place until seated.
Let excess epoxy push out around the sides.
Some epoxy will push inside the pillars. Clean this out with a toothpick as we did before.
Insert the trigger group and press firmly into place.
Check the inside of the pillars once more and clean out any epoxy.
Insert the screws, as before and pull them back out several times removing any epoxy.
Be sure to inspect and clean the threads.
Coat again with Kiwi.
Insert the screws and slowly tighten down letting excess epoxy squeeze out until they are firmly tightened down.

Wait two hours and unscrew and remove the screws. Inspect and clean if necessary.
Insert the screws again, tighten down as tight as they will go.
Wait 4-6 hours, depending on temperature and hardening, until the epoxy has taken a set.
As in the previous step, remove the screws, place the gun over your knees.
Grasping the forestock firmly, whack the barrel with the rubber mallet until it breaks free.
Turn it over and wiggle straight up and out.
Remove the trigger group.

Fill any voids in the casting by repeating the above process.

The top cast should now be complete.

Note that the tops of the pillars are just visible under a thin layer of epoxy that will flake off when lightly scraped. The “ears” that hold the trigger have created their own recess. The trigger slot will have to be cleaned out with the Dremel cutter bit.

Clean up any rough edges and excess epoxy. Assemble and screw together tightly. Let sit for two days to final hardness.
Repeat, filling voids as necessary.

Pic: top final 1-5
 

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Discussion Starter · #18 ·
STAGE 3
Trigger group
Pic: bottom holes

Remove wood from the flat areas to the 5mm depth of the holes.
Coat the trigger group and magazine box with Kiwi.
Coat the screws with Kiwi and swab the inside of the pillars again.

Fill the bottom area with epoxy, again making sure to work the deeper recesses around the pillars with a toothpick to expel any air bubbles.
Press the trigger group into place and press down until seated against the pillars letting excess squeeze out.
Clean out the pillars with a toothpick. Insert and remove the screws as previously and clean off any excess epoxy.
Seat the action and screw down slowly until tight.
Once again, at two hours, unscrew and remove the screws and inspect/ clean as necessary.
Trim off any protruding excess epoxy with an Exacto knife.
Screw back together to maximum tightness and let stand 4-6 hours until set.

Remove the screws.
Tap up and remove the receiver.
The trigger group will be solidly anchored. Before attempting to remove it, work around the edges with the Exacto knife, sanding or even the Dremel until you can clearly see the line where metal meets epoxy and no epoxy is overlapping the metal.
Insert a drift from the top through the trigger slot placing it against the flat metal on the top of the trigger slot. Tap gently both front and rear until the trigger group raises slightly out of the stock.
Use a smaller drift inserted through the front lug pillar. There is just enough of an edge to catch the metal of the trigger group. Tap lightly here until it raises slightly out of the stock. It may be necessary to use the drift and tap the solid area of the magazine box at the very front.
Work the trigger group loose from the stock.
Pics: bottom final

*Note the “tang” that was created just back from the screw hole. I failed to adequately mask this and should have diked it with putty. The epoxy squeezed into this to make a perfect casting of the recess. What I didn’t notice, until I shot it, was the base of the magazine follower has to rotate within this recess and prevented it from accepting all five rounds. The “tang” had to be ground off.
 

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Discussion Starter · #19 ·
CLEANUP

The casting process is now complete except for dressing up minor imperfections.
Cleanup any excess epoxy or high spots with the cutter head on the Dremel and 220 grit sandpaper.
Lightly, sand the sharp edges where epoxy meets metal just sufficiently to round them over (prevents chipping).

Very lightly, rough up the epoxy surfaces with an abrasive wheel on the Dremel and light sanding with 220 grit. Smooth out any obvious high spots or excess and “seams” where one layer overruns another.

Assemble and disassemble numerous times. Any areas that are binding, as in a high spot, will wear with a shiny rub mark. Lightly sand these spots with 220 grit and repeat until they no longer mark.

Final fitting should be very tight, as in a metal to metal fit, but just loose enough that the parts slide together and assemble without force.

There will be a small 1-2mm line of epoxy visible around the receiver where it meets the wood.
As the wood is sanded, this will smooth out. Small defects can be filled by scraping in a tiny bit of fresh epoxy with a sharp blade on an Exacto knife. Allow to dry and then sand flat.
Once sanded and stained, the epoxy line will be barely visible and flush with the wood.
Pics: top fit final

Note: Openings for spring and screw area on left must be left open to clear when receiver is seated or removed.
Pic: make sure this area clears
 

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Discussion Starter · #20 ·
Magazine well

The inside of the magazine well slot is pretty rough to begin with and has to be opened a bit during the bedding process. As considerable amount of epoxy will squeeze into this void, I coated the inside of the magazine well with epoxy.
A tight form fitting magazine does not work well! It needs to expand and stretch a bit to accept the rounds and will bind up feeding if it lacks clearance.
It is necessary to open this up to 1-2mm clearance on all SIDES of the magazine box.

Be sure that the recess for the spring and its tang (top of picture) have sufficient space for this mechanism to work properly and cycle the rounds correctly. If there isn’t enough room for the spring and tang to push outwards, it will bind the rounds and make feeding difficult.

The rifle is now bedded in a rock solid and indestructible base of epoxy, with steel pillars.
Screws will remain torqued tight and there is no possibility of any movement.

Pic: magazine well
 
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