Reloading help for No1Mk3*

Have a Lithgow No1Mk3* I bought several months ago, all matching and in good condition. bore is dark and a bit rough but strong rifling (5 groove)

I cant seem to get this gun to group well, even at 25 yards its like a shotgun, wondering if anyone had any advice I can try or recommendation for hand loads to try, here is what ive tried already

311 sierra match king with 38 to 43 grains of h380
316 208g noe cast bullet, 16 to 18 grains of 2400 (pure and #2 alloy)
311 175g #2 alloy cast bullet, 16 to 18 grains of 2400
308 150g jacketed hawk brand bullet, 40 grains of h380 (halved the group at 25y but still a 3 inch group)

Tried Sellier and Bellot and Prvi Partizan factory ammo and couldn't get better than 7 inches at 50y

I really like this rifle and want her to be a better shooter, any help is much appreciated.
I am still relatively new to reloading

Have you done a chamber cast what is the crown like

Have you tried 100m? The bullets might not be stabilising that close.

Many other possibilities but try one at a time.

Try to obtain some MkVII ball and see how it patterns. If it still is shooting over 4 MOA, I'd consider that the rifle or the shooter is the issue. Look up the Instructions for Armourers either 1912 or 1931 and inspect the rifle as described. The bore could be worn out, forend warped, spring and plunger missing from the nose, inner band or nose spring worn out, etc.

Guessing your barrel has been fired more than it's fair share with Mk.7 cordite ammo. Try switching the 174 SMK for the Sierra 180 grain Pro-Hunter or another flat base equivalent. Boat tail projectiles in well used LE barrels usually won't perform. It's because of the wear pattern in the throat/leade cased by cordite. Use a .310 plug gauge to check the barrel at the throat end. If it enters .25" or more, you need a new barrel.

I had a similar issue with a No1MkIII*; shooting over 12 MOA at 50 metres with SMK hand loads and PPU factory.
Barrel was worn at the muzzle and also poor fit of the wood. A replacement new old stock barrel got it half way there, and careful attention to the fit of the wood got it down to a proper 2 MOA.

No chamber cast but had the muzzle recrowned, cant be shooter error, shooting from a bench. Ive heard of some crazy stuff before but how can bullets be so unstable at 25 to 50 yards and hit well or better at 100?
When I slugged the bore it was a bit larger than new but not so large that people say to replace it, some say replace it if the groove diameter is larger that .316 or .317 and its not that large

Obviously the bullets aren't stabilizing so I suspect it's oversize. If they show stretched holes at 25 they won't be better at 100. Prove it to yourself, go out and do it.

Quote:

---

Originally Posted by browningautorifle

Obviously the bullets aren't stabilizing so I suspect it's oversize. If they show stretched holes at 25 they won't be better at 100. Prove it to yourself, go out and do it.

---

Thats what I figure but i never said the holes were stretched, im not seeing any keyholing

By stretching I mean keyholes. The hole isn't round. Anyway, I suspect your barrel is oversize so you aren't getting accuracy.

Quote:

---

Originally Posted by browningautorifle

By stretching I mean keyholes. The hole isn't round. Anyway, I suspect your barrel is oversize so you aren't getting accuracy.

---

Yes I know, theres no keyholing, and I am using oversized bullets in my current loads .316

Try the Hornady .312 174 rn bullet seated with the whole crimp groove showing and about 19.8 grains of SR-4759 or 20.8 of XMR-5744 . Use a mag primer and measure the powder well as it does not meter well . If your rifle will not shoot that load well at 50 yards I think there is something really wrong .

All the speculation is great but useless. Take my advice, go to BRP or APEX, buy the .310 and .307 plug gauges. If they respectively enter the barrel more than .25", your barrel is out of spec and needs replacing. There's no speculation using correct gauges. Everyone worried about their barrels should add these gauges to their tool kit while they're available. You need the .310 for the throat, .307 for the muzzle and .301 which must run through the barrel. If the barrel gauges in spec, you most likely have a forend bedding problem.

While test firing over 2000 different types of military rifles for accuracy I never needed a gauge to check anything to see if it would shoot . A good slug reading will get you the land and groove at the muzzle and barrel , which will tell you how much rifling you have and the sizes . If you know your land and groove and use your eyeball to check for obvious problems at the muzzle and down the bore , that will tell you what you need to know . Bedding will not cause that bad of problems at 25 yards . Gauges like that are for military armorer's to see if a weapon meets their spec but will not help much for reloading for problem guns . Try the load I gave .

As there is no such thing as a "perfect" bullet, let alone a "perfect" barrel, the slightest eccentricity of the bullet core and of the bullet in the rifling will become apparent as soon as the bullet leaves the muzzle. The bullet WILL spiral around the nominal trajectory, (precession). If the bullet were not presented to the bore such that it was perfectly co-axial, then it will start into the leade"out of whack".

When such a bullet leaves the muzzle it will then be under the influence of "drag" and gravity, despite traveling at 2440 fps and spinning at several thousand rpm.

The old Mk Vll ball was base-heavy and took a couple of hundred yards to settle down or, as the old target shooters put it, "go to sleep".

Running ANY boat-tailed bullet in an original. "much-loved" .303 barrel will do two things. Drive you nuts and rapidly eat away at the already worn throat / leade.

Remember, this is nineteenth century engineering and thought processes at work here. When the official drawings and gauging allow the nominal groove diameter to run out to .319 AT THE FACTORY and such barrels are being fed with .312" bullets driven by fast and hot burning cordite, it is all a losing battle.

Using an "oversized" bullet will work up until you get to the point that the bullet is so fat that it causes the cartridge necks to be too big to fit into even the "generous" mil-spec Lee Enfield chamber.

Then, there is the bedding for the standard barrel. This was carefully arrived at, to tune the barrel to a factory standard round, typically, the Mk Vll ball cartridge. Changing the ammo may well (very likely, in fact) nullify all of that tricky arrangement of springs, plungers and contact points. Not that there is much original Mk Vll ammo or even a commercial approximation out there, either.

If your non-performing rifle is an otherwise un-molested, all matching piece, clean it thoroughly and set it aside in comfortable retirement and buy or build a "bitza" with a NEW, commercial barrel for competition work. This will cost money, but will reduce the frustration factor enormously.

A good explanation of bullet flight and it applies to all bullets , they settle more as the range increases . That is why saying a gun shoots MOA at all distances wrong . A pointed bullet will enter a worn throat at more of an angle than a long round nose bullet seated long , like the Hornady 174 rn . A lower velocity loading will put less pressure on the bullet and let it ride straighter . A cylinder shaped bullet will stay straighter in a loose bore than a bullet with points at one or both ends . The load with the 174 has always given the best 100 yard results in my really worn 303 rifles , for those reasons .