Glock 20C vs Glock 20

[johncmng]

Since the G20 has a ported comp on the barrel, I assuming, it will have a slower velocity than the G20 with out the ported barrel. Therefore, is it safe to pack more powder into the case to "make up" for the lose in velocity? I will be reloading this cartridge and will be measuring it with a chrono.

[tundraotto]

no - the pressure spike happens before the bullet reaches the compensator. You would just increase the pressure level.

[civilsnake]

The difference in velocity would be negligible. But no, it's not safe to load powder beyond specification due to pressure in the chamber. The velocity isn't the issue. Stick with published loads until you're ready to incrementally step up through experimentation.

You'd do well to post this in the reloading forum, as well.

[Oceanbob]

No...you would just produce more 'Flaming Dirt' .

I reload 10 and just follow known recipes.

A good resource with some speeds and barrel lengths is here:

http://www.gunblast.com/10mm.htm

[DRAB_81]

Skip the "C" model, it's not worth it in my eyes. As Bob said, about the only thing that's guaranteed is flames and unburned powder shooting up into your line of sight. The porting is probably not enough to have a significant effect on recoil/muzzle flip, and negligible effect on muzzle velocity. The 10mm is very powerful, but the ported barrel isn't necessary. The Glock 20's heavy slide & large frame soaks up a ton of recoil, and make follow up shots fast and easy.

[johncmng]

No...you would just produce more 'Flaming Dirt' .

I reload 10 and just follow known recipes.

A good resource with some speeds and barrel lengths is here:

http://www.gunblast.com/10mm.htm

Great article. I was surprise that the velocity increased with a comp.

[Noah3683]

Skip the "C" model, it's not worth it in my eyes. As Bob said, about the only thing that's guaranteed is flames and unburned powder shooting up into your line of sight. The porting is probably not enough to have a significant effect on recoil/muzzle flip, and negligible effect on muzzle velocity. The 10mm is very powerful, but the ported barrel isn't necessary. The Glock 20's heavy slide & large frame soaks up a ton of recoil, and make follow up shots fast and easy.

This

[civilsnake]

Great article. I was surprise that the velocity increased with a comp.

Well the difference is that the Comp on the LW top was added to the end of the barrel, whereas the Glock "C" models are ported before the end of the standard barrel. So it's not really the same thing.

[DRAB_81]

no - the pressure spike happens before the bullet reaches the compensator. You would just increase the pressure level.

If that were true, there would be no such thing as a 9mm Major Open Gun. Compensators do have an effect on pressure in pistols. Try and shoot some 9 Major rounds through a stock G17 and see what happens. Also, like said above, a comp'd barrel is an entirely different animal than a ported barrel.

9 Major = 115gr @ 1480fps or 124gr @ 1370fps.

[modls7]

If that were true, there would be no such thing as a 9mm Major Open Gun. Compensators do have an effect on pressure in pistols. Try and shoot some 9 Major rounds through a stock G17 and see what happens. Also, like said above, a comp'd barrel is an entirely different animal than a ported barrel.

9 Major = 115gr @ 1480fps or 124gr @ 1370fps.

What he meant was, pressure is highest while the bullet is making initial movement. That's why bullet setback is dangerous, it increases pressure early on. Simply adding powder because pressure is lost down the line is not always safe. A comp will not lower this initial pressure until the bullet has traveled down the barrel and gas starts venting.