Slugging a bore

[IditarodJoe]

I have had two #4s keyholing because of boat tail bullets . They shoot flat tails just fine. Don't know if may be your problem.

I don't load my own so I'm stuck with what is available in the marketplace. Is there a commercial .303 British cartridge that's loaded with a flat tail bullet?

Both the Hornady Match and the Prvi Partizan that I've shot have boat tail bullets (says so on the box) and they both keyhole consistently. I also have some Remington High Velocity that says it has 180 gr soft point Core-Lokt bullets, and some Federal Classic that says they "feature Federal Hi-Shok and Speer Hot-Cor bullets". Does anyone here know whether either of those would be of the flat tail variety?

[Liam]

I used to shoot the Hot-Core, but thought they were discontinued. They are flat-based and, apparently, still available: http://www.speer-bullets.com/product...g/hot_cor.aspx

[PhillipM]

I'm not sure what slugging your barrel will tell you that your target full of keyholes didn't. Since you say it used to shoot fine I'd try recrowning the muzzle and if that didn't work, another barrel or get rid of it.

[IditarodJoe]

Hehe, well Phillip, I'm not sure either. Before I do anything else, I'll take my old box of Federal Classic cartridges to the range and see how it likes them (thanks Liam!).

Having never slugged a barrel myself or even seen anyone else do it (except in videos), slugging the Enfield would be a learning experience. I'm thinking (always a questionable event) that it might give me some idea of the condition of the rifling. If it looks like it's pretty well shot out, then that would likely the end of it. If slugging indicates that there's still some rifling left, I'll probably take it to a smith to see if counterboring the muzzle might return it to "round hole" status for a reasonable cost.

If I have to slug the barrel, my two primary objectives will be (1) to know a little more than I know now about the condition of the bore and (2) to learn to how to slug a barrel. At least, for the cost of a box of shotgun shells, the price is right.

[Sunray]

Biggest issue with commercial hunting ammo is the bullet comes .311" or .312" diameter, depending on who made it. And Lee-Enfield rifling isn't cut square like U.S. rifling is. More like ( ) and not [ ]. Makes the barrels look less rifled or more worn than they might be.
A No. 4 Rifle was used with a 174 grain BT bullet at 2440 FPS from 1938 onwards. This was the Mk VIII(best .303 I've ever fired was 1944 vintage DA. Stuff was 40 plus years old when we got it. Way better than the IVI crap we got later.) used by our lot during W.W. II and Korea. Any commercial ammo trying to emulate it will be a BT.
A OO pellet will do nicely as well. Just not as easy to measure as a cast .30 cal bullet.
Hornady, Prvi, Speer and Sierra all use a .311" bullet. Hornady does make that .3105 174 grain FMJ as well.
Slugging a barrel is easy. Take out the bolt. Put the rifle muzzle down in a padded vise. Drop the cast bullet/shot/sinker into the chamber followed by the 1/4" brass rod(that's longer than the rifle and barrel) and bash on it with the plastic mallet until the cast bullet/shot/sinker drop out the muzzle. Measure with a micrometer. .311 to .315 is ok. Anything bigger means the barrel is shot out and needs replacing. Mind you, if it's .313 to .315 there are always those Montana cast bullets.

[Johnny P]

Slugging the bore is to determine the bore size, and not necessarily the condition of the bore. A visual inspection should give you an idea of bore condition.

Since a M1 Rifle can only be cleaned from the muzzle, a quick check of the condition of the bore at the muzzle is to insert a loaded M2 Ball round into the muzzle. An excellent bore will show about 1/4" of bullet exposed. I have seen some of the Korean imports (Blue Sky) that would take the round up to the shoulder of the cartridge case. Same holds true for the British .303. This is a No.4 Mk.1 that appears unissued after rebuild.

Not scientific, but applying a know to an unknown. Military cartridge is dated 1945.

[Sunray]

"...Since a M1 Rifle can only be cleaned from the muzzle..." Not at all true. And the so called 'bullet test' tells you very little other than what the muzzle wear might be. Tells you nothing about a No. 4's barrel. They can vary in diameter considerably and still be considered ok.

[Johnny P]

Sorry you missed the point. The bullet check is just a quick and easy check to determine whether the bore is completely whipped out at the front, not a precision test. As mentioned, many of the Blue Sky Korean import M1 Rifle had the first inch of so of the barrel completely whipped out from using jointed cleaning rods, showing no lands at all.

As to cleaning a M1 Rifle from the rear, are you aware of any GI cleaning gear to clean from the breech?

[Nate]

180 grain bullets do work but are hard to find. Worst of my #4s is a 7.62 NATO conversion where almost every thing is 150gr or so and boat tail. But US FA rounds are flat based and perfect but will not help a .303 rifle

[IditarodJoe]

Possibly a really dumb question: I have some Olin military grade 00 Buckshot shotshells and will sacrifice one as a source of lead shot. Having never dissected a shotgun shell before, I'm thinking I can just pry open the front crimp and pour the pellets out (right?). Once I've done that I'll want to dispose of the remains of the shell. My question is, is there any reason I shouldn't just put the (shot-free) shell into a break-action shotgun and fire it?

Sheesh!! This thread is really making me aware of my ignorance!