45-70 short barrel levergun headspace problems?

[diopter]

Tried out the new production lever gun in question late last week. Owner was using Hornady Leverevolution 250Gr factory loads and all the primers were backing out. Some worked out loosed from the primer pocket just using fingertips. No signs of high pressure otherwise and recoil was not a problem for me. Don't want to say what brand of rifle just yet, just wondering if it's a chronic problem I should insist the owner bring it back. Felt no gas leaks.

 

[dahs]

On a completely unrelated note, 250 grainers in a 45-70? That's not right, plus those have HORRIBLE bc's.

 

[burnt_servo]

I don't know if this might be happening ,but something I've seen with 303 brass , there can be up to 7 thou difference between manufacturers in the rim thickness .

so if you have a rifle head spaced on the loose end of the spec , and you then use brass with a thin rim ,you now have a headspace issue .

 

[freebore]

I would first try some new ammo , Hornady loads em -up pretty warm. I suspect you got a Marlin , if this is true and an ammo change doesn't fix your issue then you may have a barrel receiver issue ,I know because I had 4 of these rifles with what is termed BARREL DROOP .It was causing my primers too walk out so far that I could not de-cap the brass on my bench because of clearance issues with the shell holder. The 250 grain Monoflex is a good bullet ,yet I agree with the above saying of its BC

I also ran out of scope adjustment,,,,,, my rounds were too low with full max adjustment ,apparently somewhere in the cooling process the receivers were off alignment with the barrel ,Marlin offered shims but It looked hideous to have the rear base jacked up like a seventies Plymouth duster I use to own