Home Forums Hunting & Shooting Handguns Glock 40 cal question

If there is anyone who thinks that the 10mm can be handloaded to as high a power level as the 40 S&W can be loaded, they could repeat my experiment:

Get a 40 S&W and a 10mm with case support to the case web.
The feed ramp can intrude no more than 0.180" into the chamber, as that is the thickness of both the case webs.

Work up to these overloads. Don't hold the gun. The recoil might injure the hand. Use a trigger string. Glock triggers need a rubber band wrapped around them for this. I can hold the Glocks in my hand for this test, as I am related to the 4 time world's strongest man. My hand still hurts for hours afterwards.
a) 10mm 200 gr 14.2 gr 800X, 1.3", the primer will fall out as the case fails.
b) 40 S&W 200 gr 15.5 gr 800X, 1.171", the case survives and can be used again.

The internet is full of posters saying, "Don't load a 40sw hot, buy a 10mm".
And 69 million people vote for Obama, too.
Those conditionally ignorant 10mm owners would be right, if they used WinClean 10mm brass with a small Boxer primer pocket. It is not easy to find.

Because the recoil is intolerable, this type of experiment is only valuable to understand some of the "kaboom talk" surrounding 40 sw and Glocks. Case support is the key to understanding many gun failures, and the usual suspects that Ackley describes; obstructed bore, wrong powder, too much powder, out of battery, modified and weakened chamber, etc.

The case heads strength [loose primer pockets] becomes much more important in strong rifles, where the recoil can be tolerated.
The SAAMI registered max average pressure may vary for different cartridges, but if they have the same case head, they are good to the same pressure for the individual handloader.

There are 4 common case heads of interest as examples:
1) 1889 7.65x53mm Mauser case head built with large Boxer primer.
Long brass life at 68kpsi in Quickload; In 22-250, 243, 6mm Rem, 250 Savage, 257 Roberts, 25-06, 260 Rem, 6.5x55 [US made brass], 270, 7mm-08, 7x57mm, 280, 300Sav, 308, 7.62x51mm, 30-06, 8x57mm, 338F, 358, and 35W.
2) 1950 designed .222 case head with small rifle primer built with a small Boxer primer pocket will have this problem somewhere above 80kpsi in Quickload; 17 Rem, 204 Ruger, 221 Rem Fireball, .222 Rem, .223 Rem, 5.56x45mm, .222 Rem mag, 6x45mm.
3) 1925 Holland and Holland 300 H&H Magnum built with large Boxer primer will have long brass life at 72kpsi in Quickload; 6.5mm RemMag, 7mm RemMag, 8mmRemMag, 264 WinMag, 300 H&H Mag, 300 WinMag, 338 WinMag, 350 RemMag, 375 H&H Mag, 458 WinMag
4) 1889 Mauser 7.65x53mm case head design, when built with a small Boxer primer pocket will have long brass life up to primer piercing; 22BR, 6mmBR, 6x47mm, 6.5x47mm, 7mmBR, 30BR, Lapua small primer 308.

What does it all mean?
There are some weak case head designs; 30 carbine, 25acp, 7.62x39mm, but the 10mm is the worst.

I take a different meaning - all are perfectly acceptable for their respective SAAMI pressure limits. I also don't fault a flower pot for being unable to make toast.

True, but it is nonetheless interesting that the 40 S&W can be pushed to higher power levels than 10mm.

So do these pistols with modified chambers and feed ramps, still function reliably as semi-automatic firearms?

Hell, try these Clarkm specials on for size:

http://www.24hourcampfire.com/ubbthreads/ubbthreads.php/topics/5153144

With Glocks and decent quality aftermarket barrels, all the examples I've seen have functioned better. In varying degrees, tighter lock-up, much less leading, less of a tendency to fire out of battery, and more accurate. It really is a no-brainer, IMO.

I welded that Glock 22 feed ramp up and cut the ramp to .180" intrusion, and it has fed everything, all kinds of hollow points.

Why Glock cut the ramp so deep and exceeded the max SAAMI chamber mouth diameter is beyond me. Maybe to feed ammo that fell in the mud.

WHAT NIGHT SIGHTS DO YOU USE? I USE A MODEL 22 FOR PRAC PISTOL COMP!