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Discussion Starter · #1 ·
I have a No4 Mk2 that shoots extremely low. Attached picture is at 200 yds with 174gr BTHP, with the shortest front sight attached. Does anyone have a gunsmith they'd recommend? Plus if in the DFW/north Texas/southern Oklahoma area I have one I can ship it to but would prefer to hand it over in person rather than trust it to UPS or FedEx.
 

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I'm not sure what a gunsmith would be able to do for you, other than take a bit more off the front sight blade with a file.
That's a pretty good group at 200m, and if you're using a 6 o'clock hold on the target, you're almost spot on.
Otherwise just wind up your rear sight, or add a bit more powder to your cases.
 

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What number / size of front sight do you have fitted ?
The sight blades are replacable and vary in size so it is very easy to DIY replace (no gunsmith needed)

Next question - what ammunition are you using, and what distance marking are you using on your rear sight ?
The only time the rear sight is accurately calibrated is when using original Military MkVII ammunition. Commercial ammunition can be many inches low (or high, or left or right) compared to MkVII.

You have a couple of options :

1) Assuming that is what you are getting with your rear sight at 200 yards, wind it up until POA = POI. It could be 300 yards, or even 400 yards. Make a note in you shooting book at actual required settings for various distances.

2) Are you sure that you have the lowest front sight blade available ? Replace front sight with one lower. Measure how low your POI is. Each change in 1-size of front blade will give you a change in POI of 3.9" at 200 yards.

Check which sort of front sight block you have as sight blades and sight bases (blocks) varied.
If you need help to identify model of sight block come back and ask.

This will show you what sight blades are available :

Rectangle Font Parallel Pattern Number
 

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It is a -0.30 sight blade. I was using a center mass hold. Ammo in question was Hornady match 174gr bthp. Rear sight was set at 200yds.
Your sights will never be 'on' unless you use MKVII ammunition.

Just 'wind up' your rear sight until you are on the X, make a note of the setting and you can then be zero'd in next time you shoot at that range.
The Mk1 sight on a No4 is ~1 MoA so if you are (say) 6" low, just go up 6 clicks at 100 yards, or 12" / 12 clicks at 200 yards

Your group looks pretty good so once you accept that the ammunition you are using is not what the sights are zero'd for and need to make your own-zero you should have some fun.

Just as an aside, if you put the rear sight onto it from a No5 rifle, you'll get ~0.5 MoA adjustments instead of the 1 MoA of the No4 sight
 

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Shooters have been recording sight calibrations for generations. So it's not a hokey fix.
Once you settle on your load simply record the sight settings as Alan suggested. Some use a notebook with a page dedicated to a particular rifle. Others use a tag on the trigger guard. Some, if possible, store the record with the rifle.
A small card in the trigger assy/magazine bottom of an M1 to a laminated file card rolled and inserted inside the butt trap of a Lee Enfield etc. Just make sure you can easily recover the card!
Tie a string to a small wad of rag or similar. Put the wad in first leaving the string hanging out. Insert the loosely rolled card then drop the string on top.
When needed, pull the string to bring the card to the top to be easily fished out.
Notebook in the range bag is the most practical. Note in the butt is for when you might forget to bring the book.
Title the loading (notebook you title the rifle then the loadings)
Two columns below that.
Range in one column.
Sight setting alongside

For example:
100 yards.......125
200 yards.......250

Whatever it works out to numerically, the system itself is simple.
Tip: fold an inside corner of the card facing outward towards yourself. Gives you something to grab to roll the card a tad tighter should the edges get hung up.

added As has already been mentioned.. Your group is already in the ballpark. You need not hire a gunsmith to show you to your seat.
 
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There are 'womans things' which would do the job and there would be no rattles, (or, could also be used as a pull thru). Make everything multi-purpose.
That would work in a dry climate. I think they might attract moisture and swell on particularly humid days?
While I've never tried them, I suspect having something swelling in the butt might lead to an unpleasant experience. Espeçially if needed to vacate quickly.
 

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or, from a Service Rifle shooter's perspective,

get some model paint, or raid the wife's fingernail polish, and mark your rear sight,

white out works too,

all are permanent enough to not wipe off w/o effort or chemicals, but won' t harm the sight
 

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I think you're just seeing the difference between the "real" Mk VII ball & the Hornady offering. Remember the "real" Mk VII ball had that filler tip, which makes the bullet longer than a traditional lead-filled jacketed round of the same mass. Probably also not Cordite-filled either so that may also be having an effect on barrel harmonics.
 

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Just to show what Plonker is referring to :

Bullet has an aluminium portion (about 30% of the length) meaning it is much longer for the same weight as a 'solid' lead bullet would be,

The bottom of the bullet is also 'open' so is very easy to 'upset' to fit properly into the rifling,


Handwriting Line Rectangle Font Triangle




Utility knife Tool Natural material Wood Knife
 

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Discussion Starter · #13 ·
Thank you all! I guess its one of those mental things that not having the sight graduations match that drives me nuts. I do have a reloading setup so I may use this as an excuse to work up some reloads. (if only 311/312 bullets were available!)
 

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Thank you all! I guess its one of those mental things that not having the sight graduations match that drives me nuts. I do have a reloading setup so I may use this as an excuse to work up some reloads. (if only 311/312 bullets were available!)
You'll get used to it soon enough. We all do.
Having sight graduations out of sync isn't as bad as having a speedometer which misreads by several mph. Or having a 4 foot level that's out of whack.
 

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Thank you all! I guess its one of those mental things that not having the sight graduations match that drives me nuts. I do have a reloading setup so I may use this as an excuse to work up some reloads. (if only 311/312 bullets were available!)
Part of the problem in trying to emulate cordite propelled, open based flat bottomed bullets is not only the supply of the correct bullets, but the very different characteristics of Cordite vs NC.

An extract :

Use of Cordite in Rifles

'Regulations For Army Ordnance Services', Vol.3, Pam.11A (1949) comments:-

APPENDIX 15

(referred to in para.29)

USE OF .303-IN CORDITE AND N.C. AMMUNITION

1. The action of Cordite propellant in the barrel of a .303-in. weapon is quite different from that of N.C. propellant.
Cordite gives a rapid build-up of pressure with great heat, leading to pitting and erosion of the chamber end of the barrel.
N.C., however, gives a more gradual build-up of pressure with less heat, and this in turn gives uniformity of barrel wear from chamber to muzzle, the amount of pitting and erosion being greatly reduced.

2. With Cordite propellant, set-up (upset) of the bullet is most pronounced and even when the chamber end of the barrel is well worn, the muzzle end still has sufficient rifling left to impart the necessary spin. As the wear advances up the barrel, so the accuracy of the weapon is progressively reduced.
With an N.C. propellant, set-up of the bullet is slow and by no means so pronounced, due to the more gradual building up of pressure. The barrel retains its original accuracy until wear reaches a critical stage, when a sudden falling off in accuracy occurs.

3. It can be seen by comparison with the effects of barrel wear that to use N.C. ammunition in a barrel which has fired Cordite will give serious inaccuracy in flight, whereas the use of Cordite ammunition in a barrel which has fired N.C. gives good accuracy, but serious changed the wear pattern of the barrel.
In the first case, i.e. a weapon which has fired Cordite ammunition the barrel will be eroded and fissured in the first few inches up from the chamber, the part in which obturation should occur. The poor set-up of the bullet, in the N.C. cartridge is not sufficient to give good gas sealing in such a barrel and the bullet does not, therefore, receive the maximum impulse. The resultant loss in velocity and instability due to lack of spin lead to a high degree of inaccuracy.

In the second case, Cordite ammunition fired from a barrel which shows uniformity of wear from firing N.C. ammunition, has an adequate reserve of set-up that ensures full gas sealing, with satisfactory velocity and spin. Unless the barrel wear is in a advanced stage due to firing a large number of N.C. rounds, there will be no immediate appreciable loss in accuracy. Furthermore, the decline in accuracy for Cordite ammunition will follow the normal gradual fall-off experience in weapons firing Cordite alone, as the wear at C of R progresses.

4. Trials have proved that even if only a few rounds of Cordite ammunition are fired from an "N.C." barrel, the ensuing accuracy life when N.C. is subsequently fired is reduced considerably. The occasional and restricted use of N.C. in a "Cordite" barrel will however, have little effect on its ensuing accuracy life for Cordite, although naturally the fire of N.C. will not be very accurate.

5.
The effect of wear of barrels can be determined by firing shots through a paper screen at 100 yards. If, on examination of the screen, all shot holes are not perfectly round, then the barrel is no longer fit for use.
The danger lies in the fact that bullets fired erratically from badly worn barrels may overcome their instability in flight and take up a steady flight in the direction in which they happen to be pointing, with short-ranging and disastrous results if used for overhead fire. Except under these conditions of long-range firing there is no risk involved, though in normal range firing inaccurate fire will result.

6. The following instructions regarding the use of .303-in ammunition have been issued to users and are governed by stocks and types of ammunition and weapons in current use:-

(a) .303 in. Vickers M.G.s in M.G. Bns.

(i)Mk.8z only will be used for overhead firing.
(ii) Mixed belts, i.e. Ball, Tracer, A.P., etc., will NOT be used.
(iii) Any barrel which has fired Cordite ammunition will NOT be used for N.C.; barrels will be stamped “7” on the trunnion block and returned to R.A.O.C. through normal channels.
(iv) Barrel life for N.C. will be assessed by unit armourers using the appropriate gauges.

(b) .303 in. Vickers M.G.s in A.F.V.s.

Here the overhead fire problem is not considered; the range is usually less than is the case with ground M.G.s. tracer ammunition is required as an aid to fire control, and prolonged fire programmes are not envisaged. Special mixed belts of Mk.8z and Tracer are provided in boxes clearly marked “For use in A.F.V.s only”. The reduced life of the barrels is accepted.

(c) Light M.G.s.

Cordite ammunition normally will be used. N.C. ammunition, however, gives a relatively small flash at night and if the Bren is being used for a special purpose, e.g., on a patrol, its use is permitted.

(d) Rifles.

N.C. ammunition will not be used in rifles except in such circumstances as quoted in para. “(c)”
above, if necessity should arise.

7. Belt packed S.A.A. for M.G.s is packed in boxes which are clearly marked with labels or stenciling indicating its proper use. It will never be de-belted and used for practice purposes in L.M.G.s or rifles.

8. It must be noted that the above restrictions apply only to ammunition fired from British weapons. All American ammunition is N.C. loaded and their weapons are designed to fire it satisfactorily.
 
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