03A3 bore

[brande]

What is the proper or good bore for an 03A3?

I have an arsenal rebuild (one punch mark) and shows no wear on the green parker.

Unfortunately, doing a bullet test in the bore with commercial 150gr ammo.
Results are bullet is 1/16 to 1/32 from the case.

What is the reasonable bore diameter? As a welder and machinist, I have the tools and ability to measure these bores
properly.

What should I be looking for?

Many Thanks

brande

Information

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[Mike D]

I don't think a commercial round will show as much bullet as a military round.

Looking at Brophy's book, Stargauge barrels, average for land diameter is .3000 - .3002, groove diameter .3080 - .3084. These are 03 barrels.

I could be wrong, but I'm guessing 03a3 barrels would be the same.

[Kirk]

The "Muzzle Wear" or MW measurement seen quoted is the the lands or tups of the rifling. The ideal land measurement is .300" On a MW gauge, that is read as 0. A barrel, even new barrels, that reads 0 is rare; many new barrels left the manufacturer in WWII with a MW as high as 3.

The "bullet test" is only an approximation since it depends on that particular bullet - in may or may not be in spec, etc.

Just as important as the MW reading is the condition of the crown; it should be perfectly round and sharp without any dings, wear or other imperfections.

[Chuckindenver]

well,
personally id put the gages down, take a day at the range, shoot it..if it shoots, then its good, if it doesnt shoot for beans..dig out the gages and tools.
KISS

[Emri]

well,
personally id put the gages down, take a day at the range, shoot it..if it shoots, then its good, if it doesnt shoot for beans..dig out the gages and tools.
KISS

......somewhat, a simple exam could save some time, range fees and ammo costs. I KISS a lot; don't make a problem where none exists in the first place, but if there is an obvious problem, address it first before shooting.
I agree, too many people make too much fuss about what the "gages show".
I just eyeball muzzles and throats. See some wear at the muzzle?? Just turn a countersink a few times to sharpen it up and then shoot for effect. Can't see any rifling for 6" in front of the chamber?? Don't shoot and look for a new barrel.

FWIW,

Emri