greenjoytj
02-04-2017, 12:09 AM
I read a lot of posts were the handloader is trying to load 40 grains of real black powder into modern 45 Colt cartridge cases, some say it can't be done and some say they can compress in 40 grains.
Original 1872 copper cases with their inside priming systems maybe could actually hold 40 grains in their larger internal volume. Modern solid head cases with possibly thicker side walls definitely have smaller internal volume.
So if an original 40 grain 1872 45 Colt cartridge could be pressure tested on today's modern pisoelectric tester, what reduced quantity of BP would be loaded into the modern reduced volume cartridge case to equal the pressure measured in the old original larger volume case? It maybe that compressing 40 grains of BP into a modern case might be exceeding the pressure of the original 1872 load thereby making the new load something the old load never was. I'm just asking cause I don't know.
If this was a modern 40 S&W ctg. and the bullet was accidentally deep seated by 35 thou high pressure would certainly occur. I see no difference whether the case volume is reduced by a deep seated bullet or a hollow balloon head case is filled in to be solid.
Original 1872 copper cases with their inside priming systems maybe could actually hold 40 grains in their larger internal volume. Modern solid head cases with possibly thicker side walls definitely have smaller internal volume.
So if an original 40 grain 1872 45 Colt cartridge could be pressure tested on today's modern pisoelectric tester, what reduced quantity of BP would be loaded into the modern reduced volume cartridge case to equal the pressure measured in the old original larger volume case? It maybe that compressing 40 grains of BP into a modern case might be exceeding the pressure of the original 1872 load thereby making the new load something the old load never was. I'm just asking cause I don't know.
If this was a modern 40 S&W ctg. and the bullet was accidentally deep seated by 35 thou high pressure would certainly occur. I see no difference whether the case volume is reduced by a deep seated bullet or a hollow balloon head case is filled in to be solid.