The Firing Line Forums - View Single Post

noylj · July 20, 2010, 06:06 PM

The quoted text:
In no case should you ever allow the cartridge to headspace on the bullet. That is not OK. The bullet needs some run on engaging the rifling. With out that run the bullet stalls in its exit from the case and the fast rising pressures can become too high. While it may not blow up the gun it may do a number on the case, or blow the primer out of the case and into your face (hot primers on the skin are not conducive to smooth skin!).

IF the bullet gets a running start and then hits the rifling, that would seem to be a great place for a pressure spike. Perfectly normal in rifles, so it must be OK. If the bullet is in contact with the rifling, by definition it can't get a running start before crashing into the rifling. I sort of think of it as a really good crimp and Unique, Bullseye, and Red Dot seem to burn "cleaner."
Having the bullet shoved into the rifling with a cartridge running at 55k pressure or more might be a problem, but we are talking about less than 35k and, with the .45 target loads, MUCH less.
Aren't battleship rifles always loaded with the bullets in contact with the rifling?
I have been setting up my .45 lead bullets loads to headspace on the bullet shoulder. Extraction has never shown any push-back and the bullet has never been shoved into the rifling more than to just leave a hint of a mark on the bullet. The main issue is feed reliability and fitting the magazine. I personally do not believe there is a better gauge than your own barrel.
Next, as a reloader, I always work up a load and have never NOT started at the starting load, and almost always check multiple manuals for the lowest of the starting loads.

July 20, 2010, 06:06 PM	#6
noylj Senior Member Join Date: October 22, 2007 Location: Between CA and NM Posts: 860	Headspace on the bullet? Only been doing it for 30 years The quoted text: In no case should you ever allow the cartridge to headspace on the bullet. That is not OK. The bullet needs some run on engaging the rifling. With out that run the bullet stalls in its exit from the case and the fast rising pressures can become too high. While it may not blow up the gun it may do a number on the case, or blow the primer out of the case and into your face (hot primers on the skin are not conducive to smooth skin!). IF the bullet gets a running start and then hits the rifling, that would seem to be a great place for a pressure spike. Perfectly normal in rifles, so it must be OK. If the bullet is in contact with the rifling, by definition it can't get a running start before crashing into the rifling. I sort of think of it as a really good crimp and Unique, Bullseye, and Red Dot seem to burn "cleaner." Having the bullet shoved into the rifling with a cartridge running at 55k pressure or more might be a problem, but we are talking about less than 35k and, with the .45 target loads, MUCH less. Aren't battleship rifles always loaded with the bullets in contact with the rifling? I have been setting up my .45 lead bullets loads to headspace on the bullet shoulder. Extraction has never shown any push-back and the bullet has never been shoved into the rifling more than to just leave a hint of a mark on the bullet. The main issue is feed reliability and fitting the magazine. I personally do not believe there is a better gauge than your own barrel. Next, as a reloader, I always work up a load and have never NOT started at the starting load, and almost always check multiple manuals for the lowest of the starting loads.