I bought a Glock 22 over 10 years ago, and it was an old one then.
If one looks at SAAMI registered toleranced drawings for cartridges and chambers, they are sloppy [wide tolerances]. They do not over lap. The chamber wide sloppy range is just above the cartridge wide sloppy range.
If one looks at actual cartridges and chambers, they both tend to be at the small end of their respective SAAMI ranges.
If from the bottom of the cartridge range to to top of the chamber range would be a distance of [2] sloppy ranges.
The clearance between most ammo and most chambers is then [1] sloppy range.
But the old Glock 22 40sw chamber did not conform to the trend.
It was so big, it did not even make it into the TOP of the sloppy chamber range.
So we put typical ammo in an old G22 chamber we have a clearance of [2+] sloppy ranges.
This makes the case change [2] sloppy SAAMI ranges when fired.
Then along comes a sizing die. It is so small that the hardest springiest brass will come out at the bottom or below the bottom of the SAAMI range for cartridges.
Now when the case is fired, it stretches [2++] sloppy SAAMI ranges.
The old G22 has feed ramp intrusion of 0.235".
The 40sw brass has a web that is 0.180" thick.
There is then 0.055" of thin unsupported case wall.
A Nosler 200 gr JHP .400" dia bullet is 0.68" long.
The 40sw cartridge is 1.135" OAL max
1.135" 40sw OAL - 0.68" length 200gr bullet - 0.18" 40sw case web = 0.265" length space for powder charge
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What does it all mean?
If the brass gets expanded and resized a long way it work hardens.
If the brass is thin over wide unsupported areas, it will blow out with less pressure.
If the powder is confined to a small volume it makes more pressure.
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What does THAT mean?
If you keep reloading like that, you will have incidents of brass failure.
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Why would Glock do that to us?
Glock gets blamed if a gun jams.
Glock does not get blamed for old worn out ammo.
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What can be done?
1) As a reloader, I own a Glock 22 barrel that I have modified to be smaller in diameter and 0.18" feed ramp.
2) As a reloader, I own a KKM 40sw aftermarket barrel with 0.20" feed ramp
Now instead of case bulges, my 40sw can push 200 gr faster than my 44 mag can. The 44 mag is limited by finger tip extraction. The 40sw can extract with hundreds of pounds of force.