Gas check diameter

[ell198679]

On my 8mm Mauser when gas checks are applied, that portion of the bullet has a wider diameter then the rest of the bullet. The portion of the bullet with out the gas check is .325 the portion of the bullet with the gas check is .333. Interestingly, enough I have not had any problems shooting these rounds with gas check applied out of my 8mm. Also, I never noticed the gas check inside the barrel or anything like that it seems to always at least eject with the boolit. I apply my gas check with a rubber mallet with out crimping perhaps crimping would remove the discrepancy 324-175-1R is the mold it should accept gas checks. Perhaps, this is normal occurrence, I have just started reloading..

[Calamity Jake]

The gas check needs to be crimped on, get a lee push thru sizer at .325Ø for your single stage press.
I"m supprised the loaded rounds even chambered in your rifle as the case neck would be expanded oversize.

[ell198679]

Thank you. I read on here that you can also use a .30 caliber factory crimp die. I tried it and after adjusting the technique works fine.

[Larry Gibson]

I suggest you also get a Lyman Cast Bullet Handbook (#3 or #4) or the Lyman #49 reloading manual and study it carefully. Learn the basics as that will better keep you out of trouble in your reloading endeavors. While expediants are helpfull to do sometimes it is always better to get the proper equipment and tools to do the job.

Larry Gibson

[ell198679]

Yes I have been looking into the Lyman Cast Bullet Handbook trying to find one that isn't 50 bucks but hey may be a worth while investment. I will likely get a lub sizer because it takes care of the lubing, sizing and crimping apparently. Something that is easy to forget if you do it step by step. However, they are impossible to purchase.... right now anyways.

[Larry Gibson]

However, they are impossible to purchase.... right now anyways.

That does seem to be the problem these days.......panic buying of everything.......

Larry Gibson

[jonk]

I have often shot bullets with gas checks not crimped, but just superglued in place. I've never had problems with the brass bulging, the case sized down the checks just fine.

The only downside is that unless crimped, they could fly off erratically causing flyers.

Otherwise it's not a problem.

The Lee push through will come in .323, but that can be honed out with some emery paper without issue.

[ell198679]

That is probably because if they are not sized by the sizer, then they are sized by the bore, chamber and or the brass. My gas checks caused my particular wolf brass to bulge so now I crimp em. They shoot fine and weren't even particularly hard to chamber...