Quote:
Originally Posted by incarcerated
The problem here is unsupported case heads, particularly w/ the .40 S&W. The .40 is a reasonably high pressure cartridge, running around 32,000 to 35,000 PSI. The designers of many automatic pistols have cut away a small crescent portion of the chamber at 6:00 to facilitate feeding as the round comes up the ramp. Remove your barrel and check it out. Cartridge brass can (doesn’t always) bulge slightly in this unsupported area near the case head. Resizing works the bulge, weakening the brass ever so slightly. When a piece of .40 brass has had the misfortune to bulge in the same place repeatedly after multiple reoladings, it can fail. When this does occur, it is usually found in Range re-loads at public ranges, or hand-loads. New factory ammo, steel case ammo (Wolf), and the 104 year-old .45 ACP (at 21,000 PSI) do not tend to experience this problem.
Springfield XDs and, if memory serves, Walther P99s are fully supported. Most Sig, Glock, Taurus and other autos generally have the unsupported (i.e. not fully supported) chamber.
Further discussion can be found:
http://38super.net/Pages/supported.html
and
http://www.hkpro.com/forum/showthread.php?p=661911 |
Incarc:
You might want to read the registration message you received and comply before posting again, or the rules and stickies posted at the top of the forums here.
TR
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De Oppresso Liber 01/20/2025
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