RDA 226sig
Member
- Joined
- Mar 9, 2008
- Messages
- 150
There have been a number of threads posted regarding 40 S&W brass that came apart during firing. Why 40? Are these cases overworked and are the failures due to strain hardening? Did the loader make a mistake? Maybe all of those things?
In an effort to answer these questions for myself I purchased five boxes of FACTORY ammunition and fired them through four different 40 caliber pistols; Glock 22, Springfield XDM, Sig Sauer P229, and Tuarus PT840. After collecting the brass and running it thourgh the tumbler I separated it by primer strikes and inspected each case.
Interestingly enough the XDM and Taurus were very consitant with regard to the diameter of the spent brass with the largest cases measuring .428 and most measuring .427 or less. The G22 was consistently measuring .429 or larger with the worst cases around .430 to .431. Typically my P229 produces spent brass that is in the .426 or .427 diameter but to my suprise a small percentage of rounds that were abnormally large with one of them measuring .433!
.433 will not go back into the chamber and I am pretty sure this had to be the result of residual pressure during extraction. These pistols are clean and in good working order, according to my Sig Sauer certified gunsmith. This reloader is going to be a bit more picky about the brass he reloads and is going to throw out some older cases.
In an effort to answer these questions for myself I purchased five boxes of FACTORY ammunition and fired them through four different 40 caliber pistols; Glock 22, Springfield XDM, Sig Sauer P229, and Tuarus PT840. After collecting the brass and running it thourgh the tumbler I separated it by primer strikes and inspected each case.
Interestingly enough the XDM and Taurus were very consitant with regard to the diameter of the spent brass with the largest cases measuring .428 and most measuring .427 or less. The G22 was consistently measuring .429 or larger with the worst cases around .430 to .431. Typically my P229 produces spent brass that is in the .426 or .427 diameter but to my suprise a small percentage of rounds that were abnormally large with one of them measuring .433!
.433 will not go back into the chamber and I am pretty sure this had to be the result of residual pressure during extraction. These pistols are clean and in good working order, according to my Sig Sauer certified gunsmith. This reloader is going to be a bit more picky about the brass he reloads and is going to throw out some older cases.