I have a Glock 20 [10mm full sized].
I have overloaded it to see how much power I can get.
The feed ramp intrusion into the chamber of the stock Glock barrel is .250", and yet the web of 10mm cases is only .180" thick, leaving .070" of thin unsupported case wall to blow out.

I got a Barsto aftermarket barrel for the G20, and although the case support is not up to the web, it is better. The stock barrel gets case bulges with 3 to 30% powder overloads, and the Barsto gets bulges with up to 82% extra powder.

The problem with the 10mm is not just the stock Glock barrel, it is the case design. The large primer [mistake] pocket and the extractor groove are so close, the thin spot in the web opens up and the primer falls out at pressures the 40 S&W and 45 acp laugh at.

This 30-30 case, I cut down, has no extrator groove, and so permits higher pressure in the 10mm

Whatever you do don't load lead bullets in glocks with factory barrels. I've seen pieces of the Glocks that used too many lead bullets. The polygonal bores don't shoot them as well anyway. Use jacketed bullets and you shouldn't have any problems as long as you keep your loads reasonable...........DJ

I got as far a 5 reloads on a batch of 100 pieces of Win brass, plus the factory firing, with my G22 (40 S&W) and ran out of courage. My loads run light...to the point that case bulge is barely measurable. Unless you are really looking for it, and know what you are looking for, you can't see the bulge with your naked eye.

Full power reloads are another story...but after many thousands of reloads through my model 22, I have yet to blow a case. I add that to the many hundreds of thousands of reloads some friends who shoot competitively have been through, and I feel safe enough.

I stay 10% below max for brass I want to last, and throw away full power reloads after 2 reloadings...just to be safe.

5.4 grains of VN340 and a 180 grain JHP is my pet practice load...note that Vihtavouri lists 6.0 grain as max with that bullet/powder combo.

You CAN reload Glocks as safely as any others...it just doesn't take as well to hotrodding as some other pistol/cartridge designs.

Isn't that mod 20 great,,,Ive had one for years now and It has never and I mean never failed to function 100%perfect with thousands of rounds through it, I shot locally in a pistol club for a couple years and went to several Glock Shoots sponcered by Glock. Lotsa rounds and no problems now that the high capacity mags are back I have stocked up!

I always shot the CCI blazer nonreloadable ammo but now that I am reloading I am waiting for a sale on 10mm brass or loaded brass ammo to stock up. I still have many many Blazer rounds I caught it on sale once and bought a 20 year supply.

Corbon makes some impressive hunting rounds for the 10mm and the Win silvertips are hard to beat for a two legged round. They also work OK for deer, expand pretty fast at close range, I have taken a whitetail at 15 yards and one at 45 yards with mine, It sports a ported 6 inch barrel from Alchemy Arms??? I think that is spelled right.

Have fun they are great guns I hope to learn from your reloading of the Glockzilla as they started calling mine around here!