Over sized boolit problems?

[jr86]

Hello all!

ive been having problems loading for a lee enfield I've got. I finally go around to slugging the barrel and it appears the barrel is smaller than it should be .308-.309ish... Maybe? 5 groove rifling can be a challenge. I've been running .313 pills though it with very poor accuracy and was wondering what kinds of effects a 0.05ish oversized boolit would do. Leading? Weird pressures?

thanks
Jeremy

[petroid]

If you can chamber the round, the bullet is likely not oversized. Many recommend loading the largest bullet that will chamber. 5 groove rifling requires a special measuring method. A quick search will bring up the info. Do a pound cast of the throat and you will learn a lot. Info about your alloy, lube and load can help others help you

[Shiloh]

What Petroid said.

There is something else going on.

Shiloh

[jr86]

I can chamber the round. But enfields are notorious for throat erosion because of the hot burning cordite. I'm using range scrap made heavily of .22s and trying to make a light plinking load with no gas check. I've tried win231 and unique. Best results being 2" at 25 yards with powder charges varying from 6-8gr.

I wrapped some shim around the boolit and measured with a caliper. Then subtracted twice the width of the shim. Gave me .307"

[RED333]

Try sizing it down a bit, worst is you get some lead fouling.
Others have said a pound cast, it is scary the first time, but done right will give
you valuable info about the throat of your rifle.

[jr86]

Scratch that. The slug measured .3145"

i had a friend at work check it on a CMM machine. Lol thanks guys

[RED333]

Well you know why the bad groups.

[petroid]

Scratch that. The slug measured .3145"

i had a friend at work check it on a CMM machine. Lol thanks guys

ok now you're getting somewhere. You're going to need at least .315" or may .316". What is the ID of a fired case mouth? Try sizing to that if it will chamber. A pound cast will also be very helpful.

[Shiloh]

Scratch that. The slug measured .3145"

i had a friend at work check it on a CMM machine. Lol thanks guys

Sounds more like it.
You will need a bigger boolit. Now you know where to start. The issue now is, can you chamber that large a boo lit.

Shiloh

[runfiverun]

.308 isn't uncommon, but they are hard to find.

you got nothing to worry about on the oversized thing.