Porting a 1911

[team06]

1911's are recoil operated, not gas operated.
All the recoil energy is transferred into the slide well before the bullet leaves the barrel.

I agree, but gas pressure is still an integral part of the gun cycling. By putting in pressure relieving ports, you are essentially shortening the barrel length. The gun will not behave exactly the same with a different length barrel or different weight barrel. There are pressure issues and inertia issues. If all of the energy is expended in only the point of firing, then why would you need to respring and lighten the slide on a comped and ported 1911 just to get it to perform as it did in a solid unported barrel? Another thing that will show up is a decrease in muzzle velocity because you have what is now a shorter barrel.

My original point still stands though, when you start modding a gun, you may well need to start tuning on a lot of areas to get it to run 100%.

MustangO3:
Good luck in your project! and if you get stuck someplace, please post on here and see if we can give you a hand through any issues. When I started shooting and building open class guns, I wish there was someone there to clue me in on a lot of these details. It would have made debugging open guns problems a lot easier.

[38super]

Expect to drop the recoil spring by 2 to 4 lbs, mainspring may need to be changed to a 19 or 17 lb. too. It appears you're still using a bushing, so there will be a large gap between the barrel and slide ports. You'll find a lot of soot in the slide after shooting. HTH

[Beelzy]

Ruined a good top end if you ask me.....which you did.

[eijjie33]

shoot it and let us know how it went

[vta]

you may want to consider drilling out more of the slide as in those first milliseconds when the slide starts to move backwards, the ports wont be able to release the gases which will defeat the purpose of compensation.

[ar15barrels]

you may want to consider drilling out more of the slide as in those first milliseconds when the slide starts to move backwards, the ports wont be able to release the gases which will defeat the purpose of compensation.

The bullet is already out of the barrel before the barrel unlocks and the slide moves to cover the ports.
The barrel and slide are moving together while the bullet is still in the barrel.
Then the bullet leaves and barrel and the barrel starts getting cammed down by the link.

[MustangO4]

Thanks for all the comments. I am basically playing with it as it is a no name, kinda worn slide and barrel. I will report when I get out to shoot it and try to get some video as well. It basically was to satisfy the urge to do this on a cheap gun, before I messed with it on a nicer gun. As of now I know I can do it, but the question is what will it give me in return. "real" gunsmiths put a lot of science and research into doing this professionally. I am just drilling holes in my gun because once I get an idea in my head, I have to do it or it keeps me awake at night. Here it is after a quickie paint job:

[Jayskuh]

Gunna be a really dirty gun to shoot no?The 45 is kinda bad i guess, but dont think this should have been done
It looks legit though =)

[vta]

The bullet is already out of the barrel before the barrel unlocks and the slide moves to cover the ports.
The barrel and slide are moving together while the bullet is still in the barrel.
Then the bullet leaves and barrel and the barrel starts getting cammed down by the link.

yes and no. It is true that the barrel link will delay the separation of the slide and barrel connected via the barrel lugs in a 1911 but the bullet might be out but gases are still on its way out behind the bullet. I would drill the bores another millimeter or 2 bigger on the slide. the difference is negligible but you will see that most commercial porting jobs will do just that.

[xxdabroxx]

how did you remove any burs from inside the barrel? I have always wondered how that is done. (Have a 4" 44mag super blackhawk that could use some holes)

[MustangO4]

I run a bore brush through a few times. If you didn't push too hard, the burrs won't be too bad. I have cut a few barrels, drilled gas ports and opened them up. I have never had issues. Any remaining small burrs will be cleaned up by the first round. That being said, I am NOT a trained gunsmith. I am a hack and don't recommend that anyone try the stuff i do in my shop.


I took it out to shoot. Fired fine for a couple of mags, then the build up in the slide started it jamming. It was a mix of FTE and FTF and the slide just getting "gunked" up. I brought it back and opened up the slide port a lot. Hopefully this will solve the issue. I will shoot it again Thursday. Here is the new port. Still needs a little cleanup and I will wait on a paintjob until it gets running right.

[38super]

Still using stock springs? Recoil any lighter, is brass flying further or less?

[MustangO4]

I shot it last night. On full power loads it is running great. Still gets a little dirty, I may open up the slide some more, but with clean ammo and good lube it is running good. I put the barrel bushing comp on and it actually does push down a little. I would not pay for it, but as it came with the gun, I'll take it for free. For a play with it gun, I am satisfied.