A GI-ish 1911 in .40 S&W conversion project

[Bigslug]

Interesting. . .

Put me firmly in the camp of those wanting to cram the .40 into its coffin impaled with a stake soaked in garlic-infused holy water, slam the lid shut, padlock it closed, and fill the grave in with roughly the amount of concrete used to build Hitler's Atlantic Wall, but hey, whatever floats your boat named Demeter.

Given that the GI recoil spring was 16#, and I've found 5" .45's to just simply feel better running 230 grain spec ammo with an 18.5#, you might give some additional thought to your lighter-than-stock spring for the "hard takeoff" .40. I'd probably also go the extra steps of a stiffer mainspring and less radiused "early" style firing pin stop. All to slow/smooth the unlocking and rearward stroke of the slide with a round known for eating the nominally 9mm spec parts of it's early generations launch platforms. The more you can do to make the pistol think it's shooting nice softball 200gr match .45 loads, the happier you'll be in the long run.

[elmacgyver0]

There is nothing wrong with the .40 S&W, if you like it, I say go with it.

[DocSavage]

I was going to suggest a heavier recoil spring as well.
I've a Ruger 1911 in 10 mm I can shoot 40 S&W with the q0 mm barrel and magazine but decided to get a 40 S&W barrel ro make life easier and ro keep from possibly breaking some thing. I surprised you just buy a slide cut for 10 mm breach face and go from there.

[jmorris]

I surprised you just buy a slide cut for 10 mm breach face and go from there.

He might think it's easier to open up the breech face than fit a slide to a frame, especially a 2nd slide to a frame you still want to fit the first.

A reason why I really like SVI slides and their removable breech faces.

https://www.sviguns.com.au/breechface/

Change it, the ejector, extractor and barrel to any caliber and back, with the exact same frame/slide fit.

[Willbird]

It might work just fine with the 9x19 barrel too. There are a fair number of 9x19 conversion barrels made for other guns that use the 40 extractor and work good enough to practice with.

Bill

[Divil]

Jarvis probably won’t have my barrel shipped until September. So everything is on hold for a bit.

[Divil]

I spoke with Jarvis and the barrel is off at their vendor getting its DLC coating. So another 3-5 weeks at the vendor then back to Jarvis for final inspection before shipping. At this rate I may have the project done by early December.

I learned an important lesson which is that the completion arc for speciality items like this is a much longer arc than I had anticipated. If I want to do another .40 1911 build in the future, I will order the Jarvis barrel earlier and skip the DLC coating and be happy with a regular stainless finish.

[MUSTANG]

A few decades ago; I believe it was SARCO that sold a .400 Corbon barrel for the 1911. I have one and shot it quite a bit in my Springfield 1911's for a while. The .400 carbon is essentially a .45ACP case necked down to .40 caliber. I used a 175 Grain Lee TC mold which was accurate and functioned flawlessly. For a Drop in barrel conversion with performance similar to the 10MM; it was a good choice. Over time, I migrated back to the .45 with 230 grain cast. Loading down slightly; can get the 40 S&W velocities out of the converted .400 carbon cases - without all of the conversions necessary to the firearm described for the project in this thread.

May have to dig into stores and try the .400 Corbon Barrel again with the price of lead today.

[deltaenterprizes]

What might be interesting is to go the fbi route chamber in 10mm then spring for 10mm lite with a simple spring change you could go from 40 s&w performance to 10mm full power.

I was going to suggest that!

[Divil]

Mustang- If this thread makes you dust off the .400 Corbon, then Rock On! Starline does make the brass to my knowledge.

To all suggesting I go the 10mm route:

Unless/Until I get the funds for a nice S&W 1006 and 4 good factory magazines, that is not happening. A 10mm 1911 is not really appealing to me. A .40 1911 is very appealing to me and after this G.I. -ish project is done, I will be doing at least 1 more 1911 .40 build.