The Firing Line Forums - View Single Post - How many times can you chamber a round safely?

rodfac · January 6, 2020, 08:50 AM

It is a problem, and has a marked affect on pressure, and not only with handloaded ammunition. I've had it with factory fresh Hornady .45 ACP rounds, Critical Duty, 220 gr. Flexlock +P, to be specific. Of the 20 rounds, five (5), set back on the 2nd chambering. I caught the first one after it induced a stoppage, then checked the others through the magazine. It was bad enough that I will not buy that type of round from Hornady again. A call to the factory resulted in them wanting the ammunition back, at my expense. Not a good answer.

The gun(s) in question were 1911's: two Rugers and a Sig that exhibited zero problems with other brands of factory rounds, nor with my handloads.

While I can't definitively point to the cause of the problem with the Hornady Critical Duty rounds, I think the nickled case (less friction than brass?) may have less neck tension than a brass one. That, plus the lack of a sufficient taper crimp. For the suspect Hornady Critical rounds mentioned above, I ran them through my RCBS taper crimper and found that they would not setback with 8 chamberings.

NRA used to recommend pushing reloaded ammunition against a solid, non-movable work bench with 40 lbs. of pressure as a means of checking the adequacy of neck tension/crimp depth. I don't know if that is sufficient as the slide velocity/impact has to be reckoned with as well.

Those that deny the pressure implications of set back should spend some time with Quickload, varying the seating depth and see what the pressure curve looks like...it's an eye-opener.

YMMv, but I'll continue to watch my taper crimp depth, and closely examine factory SD rounds that have been chambered multiple times. Rod

January 6, 2020, 08:50 AM	#28
rodfac Senior Member Join Date: January 22, 2005 Location: Kentucky Posts: 3,623	It is a problem, and has a marked affect on pressure, and not only with handloaded ammunition. I've had it with factory fresh Hornady .45 ACP rounds, Critical Duty, 220 gr. Flexlock +P, to be specific. Of the 20 rounds, five (5), set back on the 2nd chambering. I caught the first one after it induced a stoppage, then checked the others through the magazine. It was bad enough that I will not buy that type of round from Hornady again. A call to the factory resulted in them wanting the ammunition back, at my expense. Not a good answer. The gun(s) in question were 1911's: two Rugers and a Sig that exhibited zero problems with other brands of factory rounds, nor with my handloads. While I can't definitively point to the cause of the problem with the Hornady Critical Duty rounds, I think the nickled case (less friction than brass?) may have less neck tension than a brass one. That, plus the lack of a sufficient taper crimp. For the suspect Hornady Critical rounds mentioned above, I ran them through my RCBS taper crimper and found that they would not setback with 8 chamberings. NRA used to recommend pushing reloaded ammunition against a solid, non-movable work bench with 40 lbs. of pressure as a means of checking the adequacy of neck tension/crimp depth. I don't know if that is sufficient as the slide velocity/impact has to be reckoned with as well. Those that deny the pressure implications of set back should spend some time with Quickload, varying the seating depth and see what the pressure curve looks like...it's an eye-opener. YMMv, but I'll continue to watch my taper crimp depth, and closely examine factory SD rounds that have been chambered multiple times. Rod __________________ Cherish our flag, honor it, defend it in word and deed, or get the hell out. Our Bill of Rights has been paid for by heros in uniform and shall not be diluted by misguided governmental social experiments. We owe this to our children, anything less is cowardice. USAF FAC, 5th Spl Forces, Vietnam Vet '69-'73.