30-30 primer push out

[Gasoline boy]

Thank you all for the replies, my update... I didn't try the O-rings thinking first I should try neck sizing only and load up a few more. After doing this a few times the primer push out stopped and as an added benefit it groups way better. It wasn't a slouch before but if I do my part it's damn near MOA at 100. So no more full length sizing for this rifle! and once more Thank you to all who responded! Who would've thought a lever could group this well?

 

[John Y Cannuck]

Nothing to worry about. The 30-30win is rated for pretty low chamber pressures. Even with a 'full' charge or factory loads, there often isn't enough pressure to fully expand the brass to fill the chamber. What your seeing is caused by low chamber pressures. Now if you had ruptured primers or leaking gasses, carbon, etc. around the primers that's another issue.

Not quite true. The 30-30 has enough pressure to expand the case and seal the chamber. If it didn't, the sides of the cases would have powder stains after firing. It does not however, have much case stretch, so any headspace issue is usually represented by pushed out primers, unless the reloader neck sizes the cases. That done, the case should expand to chamber size and eventually stretched to the bolt face.
P.O. Ackley did a test with the model 94 Winchester where he actually removed the breach block, lengthened the firing pin, and fired it. the lever was held shut with thread, and the action did not open. The case expansion was enough to grip the chamber walls and the case did not push the bolt back, until he lubed the case.

 

[dan belisle]

There is an AI version.

Helps to solve any headspace issues as well, at least the ones related to the rim. Basically let's you run a 30-30 at very close to 300 Savage factory ballistics. Ive owned a couple over the years, good cartridge. - dan

 

[Hmatt]

"O" rings are expensive. Go to Staples or whichever store sells stationary supplies and pick up elastic bands, which will fit tight on your pinky finger.

They'll cost about $2/100 or cheaper. The last bag I purchased came from a Dollar Store.

Those tiny little hair clear/black elastics work very well. I take them from my daughters for situations like this

 

[Leatherstocking]

I suppose it depends on how far the primes are backing out. If they are just a little proud then you are correct and I wouldn't worry too much about it.

A headspace issue can be solved by setting the sizing die to match the chamber. It would be a mistake to continue to size cases down to factory length and then shoot them over and over. That will eventually cause case head separations.

Remember 30/30 headspace is governed by the rim, so sizing the case doesn’t affect headspace.

 

[tiriaq]

If there is enough shoulder for headspacing, careful sizing can result in the cartridges headspacing as if rimless. This can work quite well, often done with belted magnums.

 

[Potashminer]

^ Yep! firing on a "false shoulder" that eliminates end play of cartridge within the chamber works. That totally ignores SAAMI headspace dimensions and conventions - often a way to "make do" when an old gun has been put away wet ..., or when making brass case from something else - not the original chambering.