Colt 9mm to 38 super

[KY DAN]

I have a colt commander steel frame and want to have custom work done to it. Before I waste Clark custom guns time calling can I have a barrel fitted and extractor tuned to be able to shot 38 super in this pistol?

I plan to have original 9mm barrel rewelded and fitted to gun as well so I can have two "match" guns.

I have 500 pieces of brass and enough loading supplies and super ammo actually comes in stock at my rural king frequently so adding a new caliber at moment is not a cumbersome task.

Does anyone have any objections to this and if so please state your reasoning.

I am 29 and I have a great deal of life experience with firearms but I always chose wisdom over chance.

 

[cfullgraf]

One thing to learn is if the 9mm slide breech face will fit the 38 Super case. Otherwise, it should not be a big deal.

You will need 38 Super magazines as the 9mm magazines have a spacer in them.

 

[12Bravo20]

9mm rim diameter is 0.394" diameter while 38 Super is 0.406" in diameter. 38 Super will not fit in all 9mm slides. And if by chance 38 Super will not fit in your slide, you can always use 38 Super Comp/rimless which is the same size as 9mm.

And sometimes you get really lucky and don't have to fit a barrel to the slide. I got lucky when I bought a 38 Super barrel from Rock Island Armory for my RIA 9mm. Maybe I should have bought a lottery ticket after that too.

I am actually using Starline 9mm Largo brass in mine. Yes I checked all the dimensions first and the length after sizing is 0.900" I use 38 ACP dies to load them.

As far as the extractor goes, sometimes you have to tune them and sometimes you don't. Try it first as is before tuning.

 

[bannockburn]

KY DAN

I found that the opposite way by starting with a .38 Super and adding a complete barrel assembly in 9mm. to be an easier way to go. This is because if you start with a 9mm. slide you're going to have to shorten the ejector as the 9mm. one is too long to handle the longer .38 Super case. A shorter .38 Super ejector will work fine in handling the 9mm. case as well.

I like to use a complete 9mm. barrel assembly as it saves time and effort when you go to swap out parts to make the conversion. I also have 9mm. magazines as they have a spacer in them to accommodate the shorter 9mm. round.

 

[fxvr5]

9mm rim diameter is 0.394" diameter while 38 Super is 0.406" in diameter. 38 Super will not fit in all 9mm slides. And if by chance 38 Super will not fit in your slide, you can always use 38 Super Comp/rimless which is the same size as 9mm.

The 38 Supercomp is a little smaller than the 9mm. Their rims measure about .386", with some brands a little smaller.

 

[12Bravo20]

I have found the same with 9mm Largo brass too. Starline is one that tends to be on the smaller side. All of my Starline 9mm Largo brass measures 0.386" at the case rim.

 

[Cemetery21]

I've done it both ways. One was a new Springfield 9mm sent to the custom shop for a match 38S barrel/bushing. It runs perfectly with both and it also doesn't care if it's 38S comp brass or not. Springfield did shorten the 9mm ejector and tuned the extractor.

The other is a Colt 38S that I fitted with a 9mm barrel. It also runs both.

Side note: in my pistols, 9mm runs fine in 38S mags.
Just get a barrel with the same ramp style as your frame.

 

[12Bravo20]

As you can see when it comes to the extractor, ejector, and magazines some times they need tweaked/replaced and some times they don't.

Rock Island uses the same ejector for both 9mm and 38 Super (longer extractor) and my RIA 9mm works fine. I did have to tune the extractor though. I haven't tried using the MecGar 38 Super mags yet for 9mm so can't say there.

 

[Howland937]

Entirely anecdotal, but I ended up with a 38 Super barrel first. It's a Wilson/Nowlin ramp cut, so that narrowed down the options when looking for a gun. Then purchased a Kimber LW 9mm, pack of various weight but heavier recoil springs and some 38 Super mags. Stuck it together and never needed to do anything else. Function was great with factory and reloaded ammo, and 9mm fed from the 38 Super mags without fail.

Picked up a Sig Match Elite 9mm and sold the Kimber. Same barrel, recoil spring and using the same mags, function is perfect. Maybe I just got lucky twice, but I've never had any issue switching back and forth.

 

[Rock185]

As long as there is no breech face issue, and doubt there will be, these conversions are pretty easy within my humble experience. I have occasionally done a dual caliber 38S/9mm conversion on Colts or Kimbers. If your 9mm Colt has that super long ejector, you'll need to trim or replace. I've found the slightly extended 38S ejectors to work without issue in my 9mm Colts.

 

[CoalCrackerAl]

I think you will enjoy the 38 super round. The only G.I model 1911 i have is 38 super.

 

[Walkalong]

This one took no tweaking at all, but I went backwards, .38 Super to 9MM, it runs with either one.

Series 80 Enhanced .38 Super with a drop in 9MM barrel. Lots of fun.