SIG Sauer 1911 Ultra Compact 9mm? Anyone?

[Howland937]

Just wondering if anyone here has one? Was eyeballing one earlier and got to wondering. Looking at some specs online, it appears there's not a huge difference in the .45ACP (what I have) and the 9mm. Mostly trying to decide if I wanna buy a 9mm barrel and try to make a conversion. Barrel ramp cut appears the same and of course length is. My question is diameter since this is a bushing-less design.

9mm is described as a "bull barrel" and I'm curious if they just cut all the barrels from the same blanks and possibly used all the same frames. I know the full size are different, and it's pretty obvious visually. These, not so much.
But the guy that had it wouldn't let me try to swap out parts to check fitment.

 

[Lo-Profile]

There's more of a difference that what you think there might be.
I don't recall all that's involved, but it wasn't cost effective.

 

[Howland937]

I know there's a big difference on full size since the 45acp barrels aren't ramped. My ultra compact barrel is ramped very similarly to the full size 9mm with the Wilson/Nowlin cut.

Nevermind. I'm sure the breech face is also different...so I guess it's kinda moot without a new slide. Was just thinking of the ultra compact with a 9mm barrel re-cut to 38 Super would be a fun carry option.

 

[Lo-Profile]

Swapping from 9mm to 38 Super is easy.
Barrel, bushing and recoil spring. You can even use 38 Super magazines with 9mm

Yeah, a whole different slide, ejector and some other internals and springs

 

[Howland937]

Yeah, I've already done the 9mm to 38 super, but it's in a full size. The ramp cut on my 45 Ultra Compact is definitely the same as the 38 Super and 9mm, so I could definitely get by with a complete 9mm slide.

 

[Blue68f100]

Barsto makes quite a few conversion barrels for Sig's. Don't know if they make one for your application. You may want to see it they have one. If they do I may be drop-in, or minor fitting.

 

[BBBBill]

Barsto makes quite a few conversion barrels for Sig's. Don't know if they make one for your application.

As the OP realized in post #3, the breech face of a 45 slide is too big for a 9mm. You can get by with a 40/10mm slide, but one made for 9mm is far better.