Fixing the Glock .40 S&W Bulge

The trouble with the .40 Smith & Wesson cartridge in the Glock pistols has been well documented and has been discussed ad nauseum on the Internet forums. Here's how to fix the Glock .40 S&W bulge.

What causes the problem known as “Glock .40 S&W bulge” is that part of the chamber is unsupported and when firing, the pressure allows the case to expand and bulge. There are multiple reports of ruptured cases resulting in damage to the guns and shooters. This is, apparently, mostly a problem with handloads. The theory is that if the case is bulged the first time it is fired and that bulged area is oriented in the unsupported section again when the handload is fired, it can rupture.

All I can add to the argument is that I have owned a Glock Model 22 in .40 S&W for 15 years and have fired thousands of rounds. The guy hanging around my daughter for the past several years, Brendan Burns, has a Model 23 and he has probably shot three times the ammo through his as I have mine. Granted most have been factory loads, but in Camp Towsley no gun is ever exclusive to factory ammo and more than a few handloads have been through both guns. We have never had a problem. Not one, zero, nada. But, the technical side of me understands that this is not a particularly good design and the potential for a problem is clear and present.

Ammo is in short supply these days, but I am not going to let this Obama-induced scare keep me from the sport I love most. One way or the other, I am going to shoot and hoarding ammo serves little to aid that goal. With the current ammo shortage and escalating prices, my factory ammo reserves are depleted so we are shooting a lot more handloads, and handloads are where the Glock problems rear their ugly heads most often.

The trouble is that a conventional resizing die does not completely remove the “Glock Bulge” from the case. This introduces two problems; one is the obvious potential for a case failure. The other is that a misshapen case is a jam waiting to happen. Which brings me to the reason for this column. Redding Reloading Equipment has a new tool called the G-Rx die set. I was lucky enough to be one of the first to see this tool and it’s been on my reloading bench for several months.

The die screws into your reloading press and the “pusher rod” replaces the shell holder. To use it, simply place a lubricated .40 S&W case on the pusher rod and pull the handle on the press. This starts the case into the die in a tapered section that aligns it, then the pusher rod pushes the case through the die, forcing it back into size and shape before the case pops out the top of the die. A collection bottle that fits on top is optional.

Now every .40 S&W case we are loading is pushed through this die first. Problem solved.

Even if you don’t shoot a Glock, this tool is still a very good idea. If you collect or buy range brass you have no way of knowing if it was fired in a Glock. The Redding G-Rx die restores the brass to ensure that it will function well in any pistol.

Check it out at:
Redding Reloading Equipment
792 Ridge Road
Lansing, NY 14882
(607) 753-3331
www.redding-reloading.com

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