Colt 1911 38Super to 9mm Conversion

[Ματθιας]

I have a Colt 1911 in 38Super and I have been wondering about converting it to 9mm. I've read different things, but I wanted to ask you all before I start dropping money.

Is it as easy as dropping in a 9mm barrel and magazines or is there more than that? Is it worth it?

If it's just a barrel and mags who makes a decent barrel or should I look to auction sites for a used one?

Thanks!

 

[DWalt]

I have a Colt 1911 in 38Super and I have been wondering about converting it to 9mm. I've read different things, but I wanted to ask you all before I start dropping money.

Is it as easy as dropping in a 9mm barrel and magazines or is there more than that? Is it worth it?

If it's just a barrel and mags who makes a decent barrel or should I look to auction sites for a used one?

Thanks!

Nothing to it. All you need is a 9mm barrel and magazine. You should be able to find a 9mm barrel and magazine easily on eBay or one of the auction sites. Have done it for many years. .38 Super and 9mm slides are essentially identical. You may want a lighter recoil spring to use with 9mm. You can go from 9mm to .38 Super the same way.

I have discovered that using a .38 Super magazine for 9mm is unreliable, better to use a 9mm magazine.

You did not ask the question, but a .45 ACP slide, barrel, magazine, and ejector will allow you to use your same frame for .45 ACP. You may have to do a little slide fitting, or maybe not.

I am sure someone will jump in and say 9mm-.38 Super swapping shouldn't be done, but I am here to tell you it will give you no problems at all.

 

[Ματθιας]

Nothing to it. All you need is a 9mm barrel and magazine. You should be able to find a 9mm barrel and magazine easily on eBay or one of the auction sites. Have done it for many years. .38 Super and 9mm slides are essentially identical. You may want a lighter recoil spring to use with 9mm. You can go from 9mm to .38 Super the same way.

I have discovered that using a .38 Super magazine for 9mm is unreliable, better to use a 9mm magazine.

You did not ask the question, but a .45 ACP slide, barrel, magazine, and ejector will allow you to use your same frame for .45 ACP. You may have to do a little slide fitting, or maybe not.

I am sure someone will jump in and say it shouldn't be done, but I am here to tell you it will give you no problems at all.

Thanks, thanks for the info! What are the optimal spring rates for 9mm and 38Super?

 

[DWalt]

Thanks, thanks for the info! What are the optimal spring rates for 9mm and 38Super?

Your existing .38 Super recoil spring may be OK. I carry about five different spring strengths with my setup. Just use whatever spring weight causes empties to fly no more than three or four feet from the gun with whatever loads you use.

Everything said applies to barrels with unsupported chambers. That is what I have. No experience with supported chamber barrels.

One further detail. My .38 Super barrel is actually a 9x19mm barrel that I rechambered to 9x23mm Winchester. But it handles .38 Super ammunition equally well. My normal reloads use Starline .38 SuperComp cases, basically rimless .38 Super. I also have a good supply of 9x23mm Win brass for very hot loads.

 

[Rock185]

I've done a few of those conversions on Colts and Kimbers, and my experience is similar to DWalt's. That being said, sometimes the new barrel may need some fitting, an extractor adjusted, etc. Usually not a big deal. The most recent .38S to 9mm I did was on a Kimber. I did need to fit the aftermarket barrel I used, but didn't even need to change the recoil spring or ejector, adjust the extractor or anything else really, other than using 9mm magazines. I've had this pistol for a few years and probably have about 1500 rounds of each caliber through it. Shooting all manner of 9mm and .38Super ammo, I have had precisely one malfunction in each caliber..

FWIW, I also have a Colt Gold Cup 9mm I converted to .38 Super. Almost as easy, and it's more reliable with with the two .38S barrels I have than with the factory 9mm barrel.

 

[STCM(SW)]

My PT 1911 in 38 Super is a better round but do have the barrel and spring for 9 mm.
Only because of the cost difference in ammo at one time......
Now, it makes no difference in cost and back to a better defense cartridge in my opinion......
I hand load for both...

 

[minconrevo]

In an optimal, 100% dependable sense, the slide breech dimension of a 9mm and a Super 38 differ. That is because the case head dimensions differ when optimized. You may get the swap to run, but don't expect optimal accuracy from both with the same slide. The magazines are definitely different.

 

[stansdds]

Although there may have been a time when the breech face of 1911 slides in 9x19mm and 38 Super may have had different dimensions, most modern slides will have the same dimensions for both cartridges. A barrel and 9mm magazines should be all that is required to convert a 38 Super to 9mm. Factory 38 Super ammo is scarcely more powerful than 9mm +P ammo, so the 38 Super recoil spring should work just fine with 9mm.

 

[Old Corp]

My 'Super' is a RIA in 5" GI configuration, with supported chamber.
I bought a RIA 9mm barrel, and already had a mix of several M1911 9mm mags.

Actually, I was surprised how easy it was - and the OE recoil spring has worked fine with every 9mm load I've tried.

Did it mainly 'cuz my range is grass and weeds and I HATE losing .38 Super brass! Don't care if I lose much 9mm - have so much I'll never use it all.
Good luck!

 

[AJ]

I have several M1911's. I have one that started life in 1958 as a .38 Super. Someone turned it into a .38 Special, by rechambering it. As of now it is a project gun. I have a 9MM barrel, the ,38 Special barrel, a .38 Super barrel , a 40 Cal barrel and a 10MM barrel for that frame and slide combo. I also have a ,45 slide and barrel for it. Oh and also a Colt Conversion Unit in .22LR for it. Fun project.

 

[DWalt]

Factory 38 Super ammo is scarcely more powerful than 9mm +P ammo, so the 38 Super recoil spring should work just fine with 9mm.

True enough for factory loads, but if you reload, especially using Starline .38 SuperComp cases, you can exceed 9mm performance significantly. My hot load with a 124 grain jacketed bullet has a MV of around 1450 F/S. I don't shoot it much any more, but it is there if and when I want it (8.7 grains of AA#5). I do use a heavy spring.

 

[stansdds]

True enough for factory loads, but if you reload, especially using Starline .38 SuperComp cases, you can exceed 9mm performance significantly. My hot load with a 124 grain jacketed bullet has a MV of around 1450 F/S. I don't shoot it much any more, but it is there if and when I want it (8.7 grains of AA#5). I do use a heavy spring.

I agree, if you reload you can load the 38 Super to its full potential, just like the 10mm Auto.

 

[SuperMan]

Depending on the maker...one can run 10mm/.40 S&W and .357 SIG all on the same slide as the 9mm/Super.

Kimber for sure uses only one breechface cut for both 9mm and 10mm slides. Have a Stainless Target II .38 Super that has all of the above barrels and a Campguard 10mm that has had a .38 Super barrel added to it...zero issues with reliability...

Added a .45 slide to the Stainless Target II but instead of changing ejectors just had my smith deepen the .45 slide ejector channel to fit the Super ejector....zero issues with reliability...that added .45 ACP and .45 Super to the package...

All-In-One 1911 | Single-Actions

Bob

 

[Grayfox]

Why on Earth would you want to convert a perfectly good .38 Super to 9mm? 9mms are everywhere. Everybody makes 'em.
OTOH good 38 Supers are hard to come by. Don't screw up a good gun.
I went the other way. I bought a 9mm 1911 just to try one out. Hated it! Changed the barrel to 38 Super and now love it.

 

[Dvus]

I have a Nowlin built 2011 in .38 Super and shoot 9mm in it for cheap practice. No changing barrels or anything. Yes, I know the 9mm is only headspacing on the extractor, but it works fine for practice with only a bobble about 1 in 20 rounds. That gives me practice for clearing stopages. I would not recommend it for anything more serious than paper punching.

 

[stansdds]

Why on Earth would you want to convert a perfectly good .38 Super to 9mm? 9mms are everywhere. Everybody makes 'em.
OTOH good 38 Supers are hard to come by. Don't screw up a good gun.
I went the other way. I bought a 9mm 1911 just to try one out. Hated it! Changed the barrel to 38 Super and now love it.

Availability of ammo and ammo cost. Tons of 9x19mm once again on the shelves and compared to other centerfire pistol calibers, it's darned cheap. Swapping barrel and magazine is certainly not going to screw it up.

 

[DWalt]

Speaking from experience, firing 9x19 in a .38 Super barrel is not a good idea. The 9x19 case will headspace on the extractor claw, not the case mouth, and sooner or later the extractor will fail. I had it happen to me once. The extractor claw separated. I welded it back up and shaped it with a file, but did not use 9x19 ammunition again. The 9x19 should always headspace on the case mouth. So you should use a 9x19-chambered barrel.

In my incident, the fired 9x19 case remained in the chamber and did not extract.

 

[DWalt]

Added a .45 slide to the Stainless Target II but instead of changing ejectors just had my smith deepen the .45 slide ejector channel to fit the Super ejector....zero issues with reliability...that added .45 ACP and .45 Super to the package...

All-In-One 1911 | Single-Actions

Bob

I suppose you could do that but as it takes maybe a minute to swap ejectors, why bother? My answer to 10mm/.40 is to get a .400 Cor Bon barrel. The .400 Cor Bon will do anything a 10mm will, except you need to form cases from .45 ACP and load your own. Only drawbacks are you have to handload as I don't think .400 CB ammo is available today as a factory load, and magazine capacity is limited to 7 or 8 rounds. Those limits do not bother me at all. In my situation the .400 CB groups better than any other caliber with lighter lead bullet loads. Too bad it never caught on. It is a good cartridge.

My .38 Super barrel is actually a 9mm barrel that I rechambered for 9x23 Win as I mentioned previously. Works for .38 Super as well. Still have most of a case of 9x23 Win that Winchester handloaded for me for a special USAF project using 124 grain M882 bullets.

I have understood that .45 ACP M1911 magazines work OK for 10mm/.40. Have you tried that? I would like to get a 7.62x25 barrel for a 1911, but I have read that does not work so well, partially because the factory 7.62x25 COAL is too long.

I like the idea of having guns with multi-caliber capability.