slugging the bore

[eljefe]

There seem to be quite a few newbies whose enthusiasm for guns unlimited is infectious.Made me get off my hands and slug my 303-so that I could post it here.
steps
1.GUN IS UNLOADED- no exceptions.Remove bolt and magazine as well.
2.Keep butt on a firm surface, not a carpet
3.Take a lead ball, slightly larger than the bore dia.
Keep on muzzle and strike with a hammer,drivin g it into the bore.
use 6-8 inch engths of dowel-in this case ,its 6mm dia dowel, to drive the lead through the barrel.
4.keep a cloth in the action to catch the slug and prevent it from getting
deformed if it falls on hard floor.
5.measure the slug

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[snIPer]

Thats nice. Thanks
/s/

[nagarifle]

a genius or what amigo?

[MoA]

I have never really had the need to slug a bore. What made you do it?

[nagarifle]

he did it for me and el jefe was feeling the blood rush to his head, as that s what happens when your are down under.

[Sakobav]

he did it for me and el jefe was feeling the blood rush to his head, as that s what happens when your are down under.

[TwoRivers]

I have never really had the need to slug a bore. What made you do it?

There are three good reasons: a. Curiosity b. An unknown rifle/chambering/caliber c. Finding out the exact groove diameter for cast bullets, up to .003" larger.

[MoA]

I have never really had the need to slug a bore. What made you do it?

There are three good reasons: a. Curiosity b. An unknown rifle/chambering/caliber c. Finding out the exact groove diameter for cast bullets, up to .003" larger.

Curiosity is one thing, cast bullets another. With a known caliber the dia is a known comoddity. I always though that the .303 should've measure .310 or thereabouts.

[TwoRivers]

No, exact bore diameter, especially in older military rifles is not a known commodity. With a usual tolerance of .002" on the diameter, often relaxed in war time, it's a good idea to slug the barrel. Smaller nations often re-cut rifling when it became worn. And with lead bullets we are often talking of rifles that were made in the 1870s to '90s. By different manufacturers, before any standardization. Often with different rifling profiles, though the same caliber. With barrels of modern manufacture, the groove diameter is pretty much a given. Though .002"/.05 mm is still acceptable tolerance on diameter.

The .303 British has a nominal .303" bore diameter, .314" groove. Post WWII the allowable bore dimensions for the No.4 were .301" to .304". British military barrels could be up to .320" in groove diameter before being rejected; during the time when grooves in the forward part of the barrel were deepened to reduce friction. Accuracy, as well, I would venture to guess.

With the five-groove rifling of the S.L.M.E. #3, either bore or groove diameter is impossible to determine without a special gauge block. With calipers or micrometer you are measuring land-to-groove diameter.

Cheers.

[eljefe]

I have never really had the need to slug a bore. What made you do it?

There are three good reasons: a. Curiosity b. An unknown rifle/chambering/caliber c. Finding out the exact groove diameter for cast bullets, up to .003" larger.

Curiosity is one thing, cast bullets another. With a known caliber the dia is a known comoddity. I always though that the .303 should've measure .310 or thereabouts.

I was given a couple of hundred 155gr FMJ projectiles, which miked out to 308-some of the regulars were using these for years in their smelly's, and very happy with the performance

Yup, wanted to see how good a bore this smelly had-Cast bullets are being used for some smelly matches, so what am I getting into? and the ones I am reloading now are the 174FMJ running .311"
Finally, I have a exec condition 2 groove 303 bbl waiting to go on in case this one needed to go...

...And read a couple of posts on "unknown calibers, 7.92 mm confusion"-dont feel like doing a chamber casting with sulphur just now, maybe if I get 'cerrasafe' alloy?

Oh, the groove dia is .309

[TwoRivers]

Asif: What's the number of grooves in your barrel?

[eljefe]

2 Walt, its a No.4 Smelly, made by Enfield

[TwoRivers]

2 Walt, its a No.4 Smelly, made by Enfield

Come to think of it, you mentioned that in an earlier post. That one should handle .308" bullets well. Would be interesting to know whether they just got sloppy; or actually changed specs, and allowed such deviation of tolerance.

[Sakobav]

eljefe

Do post pictures of the SMLE as is now and whether its IOF or Aussie make?

Cheers

[TwoRivers]

The No.4 was made in the UK, US/Savage, and Canada/Long Branch only. Australia and Ishapore stuck with the Mk.I.