Two Random Questions

[wIg SpLiTtEr]

1. Why is it that you get glock bulge in reloads but not factory ammo?

2. Is .126 thou too deep to uniform primer pocket and ensure reliable ignition? Just wondering because I think my tool is slowly cutting deeper and deeper as steel wears off the base(part that head stamp bottoms out on)?

Thanks for the input!

 

[ksthomas]

Re: Two Random Questions

1, The bulge is caused by the fact that Glocks have an unsupported chamber. That is, a portion of the brass isn't backed or supported by chamber walls, which allow it to expand more than it would otherwise. This is what leaves the bulge. Take the barrel out, and drop a round in the chamber. Take a look at the area of the case just above the feed ramp, and you'll notice that you can see a portion of the side wall of the case ahead of the extractor groove. That's the portion which is unsupported and where the expansion takes place. Compare that to say, a S&W autoloader, and you won't see that much of the case; the chamber extends all the way back to the extractor groove, or is fully supported.

2, You're not wearing steel off the cutting tool by turning it against the face (head) of a brass cartridge case. You're fine here, don't worry about it.

 

[wIg SpLiTtEr]

Re: Two Random Questions

Thanks for the reply! I understand why this bulge occurs, I was just curious as to why it happens with reloads but not factory ammunition.

 

[MtnCreek]

Re: Two Random Questions

It sometimes happens in factory ammo. I have a lot of speer once fired in 9mm and 40sw from a police range. Many have a slight bulge. If your reloads are producing a bulge, you should consider backing off on the charge.

I load once fired 9mm pretty hot with HS6 for a Gen2 G17 without problems. After first reload (brass is now on second firing), I back off to a mid range load with HP38. I have loaded 9mm brass several times with hot loads, but decided I was tempting fate and changed my practice.

With a Gen3 G22, all reloads are mid range loads. Any defensive loads or copies of defensive loads (Horn HAP's) are loaded with new brass. After being fired at near max, they'll go in the once fired (mid range) box. That may be a little overly conservative, but I still have all my fingers and eyes.

 

[ksthomas]

Re: Two Random Questions

Oh, it happens with the factroy ammo too, it's just not as pronounced. But a quick check in a Wilson Chamber gage will show this very quickly. Just becomes more noticeable on the second go-round. There's a couple solutions to this, such as the Redding push through dies, and the plate sizing machines that some USPSA shooters have taken to.

Best solution, though, is precisely what MtmCreek describes; back the loads off a bit, and don't try to firewall them in any gun (not just the Glocks) which have an unsupported chamber. That goes tenfold for the 40 S&W, which can be a touchy little SOB to load for anyway. Factory ammo for defensive/duty rounds, and mid-range handloads for training ammo. Definately don't want to push that one.

 

[wIg SpLiTtEr]

Re: Two Random Questions

Thanks a lot guys, y'all have cleared me up a bit!