CaptainMal
Silver $$ Contributor
Own a few Marlin 336 lever rifles in different calibers. Posted an article on the Marlin Owners Forum on loading for a 30-30 lever and shooting "long range". Couple responses noted and warned of my not crimping bullets and movement during recoil and magazine tube reloading. My response was "bull". It's not needed but just how much pressure is required to move a seated 30-30 bullet?
YOU are way more technical than the Marlin group. Let me say I measured interference fit by taking cases, using the RCBS Case Master and a good mike to measure neck thickness, fired outside diameter, re-sized diameter, neck thickness again and did a quick run-out check. Also measured the Sierra 150 gr. flat points diameter and the bearing length of the seating depth. That was .35" and not all the way to the bottom of the neck but more than bore diameter.
This may have little to do with pressure required to move bullets OUT as I did not test that issue. Only tested pressure to push the bullets in.
Surprised that one case only had .003" interference fit. Two others had .004" and one had .005". That was the range and I thought it would be easy. Just used a bathroom scale to push down the bullets into the case and read the scale. Close enough for government work.
About 30 lbs of downward force on that .003" interference case is all I could do with my old, arthritic bare hand. The bullet never moved.
Used a shell holder for the 30-30 and placed that into a socket so I could get a better handhold. 60lbs and the bullet moved and pushed in. That's with only .003" of interference.
Grabbed another one and nothing. I could make a Herculean effort and get above 70 lbs and that's about all I could do with that hand on the socket without pain. Lots of pain. I could NOT move those with the .004" and .005" interference and never did.
This test would only be applicable to the caliber and components at hand. I doubt you can transpose these results to other issues and remember - there was .35" of bullet seating contact.
My conclusion to the Marlin Group is you do not need to crimp the case mouth into a cannelure with any kind of reasonable interference fit. I did not anneal these necks, know little about their hardness, know only what I just related.
Man it's a heck of a lot of pressure to move those bullets and doubtful any magazine tube or light recoil would move these bullets.
YOU are way more technical than the Marlin group. Let me say I measured interference fit by taking cases, using the RCBS Case Master and a good mike to measure neck thickness, fired outside diameter, re-sized diameter, neck thickness again and did a quick run-out check. Also measured the Sierra 150 gr. flat points diameter and the bearing length of the seating depth. That was .35" and not all the way to the bottom of the neck but more than bore diameter.
This may have little to do with pressure required to move bullets OUT as I did not test that issue. Only tested pressure to push the bullets in.
Surprised that one case only had .003" interference fit. Two others had .004" and one had .005". That was the range and I thought it would be easy. Just used a bathroom scale to push down the bullets into the case and read the scale. Close enough for government work.
About 30 lbs of downward force on that .003" interference case is all I could do with my old, arthritic bare hand. The bullet never moved.
Used a shell holder for the 30-30 and placed that into a socket so I could get a better handhold. 60lbs and the bullet moved and pushed in. That's with only .003" of interference.
Grabbed another one and nothing. I could make a Herculean effort and get above 70 lbs and that's about all I could do with that hand on the socket without pain. Lots of pain. I could NOT move those with the .004" and .005" interference and never did.
This test would only be applicable to the caliber and components at hand. I doubt you can transpose these results to other issues and remember - there was .35" of bullet seating contact.
My conclusion to the Marlin Group is you do not need to crimp the case mouth into a cannelure with any kind of reasonable interference fit. I did not anneal these necks, know little about their hardness, know only what I just related.
Man it's a heck of a lot of pressure to move those bullets and doubtful any magazine tube or light recoil would move these bullets.
