Breach face dimensions for 1911s of 3 calibers

[peacebutready]

A company that makes or made 1911s in .45, .40, and 9mm, could they have used breach face dimensions that are the same for all 3 calibers, as crazy as that sounds?

 

[wally]

Not very likely. Maybe the 9mm & .40S&W could work as 9mm "conversion" barrels generally work well in .40S&W Glock and M&P pistols.

 

[Rock185]

I've had at least 4 guns with .40/10MM breech faces that workered 100% with 9MM,38 Super and 9X23 Winchester. I seem to recall someone posting,I don't recall which forum, that they had converted a gun with .45 breech face to 9MM or .38 Super. If so, I can't argue with success, but I would be surprised that a 9MM or 38 Super would work reliability with the .45 breech face.....ymmv

 

[peacebutready]

.40 breech-face for 9mm, .40, and .45?

Not very likely. Maybe the 9mm & .40S&W could work as 9mm "conversion" barrels generally work well in .40S&W Glock and M&P pistols.

I've had at least 4 guns with .40/10MM breech faces that workered 100% with 9MM,38 Super and 9X23 Winchester. I seem to recall someone posting,I don't recall which forum, that they had converted a gun with .45 breech face to 9MM or .38 Super. If so, I can't argue with success, but I would be surprised that a 9MM or 38 Super would work reliability with the .45 breech face.....ymmv

I'm actually wondering if a .40 breech-face was used for 9mm, .40, and .45. The .45 breech-face I'm thinking about seemed smaller than any I recall looking at. Also, when loading a round, the ejector would put a small dent in the primer. Hmmm...

 

[AlexanderA]

I have the slides from two RIA/Armscor 1911 clones in front of me as I write this, one from a .45 gun and the other from a 9 mm. The breech faces are definitely not the same. The 9 mm is narrower, and it's machined for a wider ejector. Also, the hole for the firing pin is smaller, and the extractor is placed a bit differently.

On the other hand, the fronts of the slides are the same. The RIA 9 mm barrel has the same outside profile as the .45 barrel, and it uses the same barrel bushing. The RIA 9 mm barrel is very thick-walled.

I found that you can use the frame from an RIA 9 mm to build a .45 gun, as long as you replace the ejector and do a little work on the feed ramp with a Dremel (not so much to widen it but to slope it forward a bit more).