Would like to convert my 220 to 38super. Need info on what parts it will take to make this work.
Can I just get a barrel,Will I need differant mags ,Will I also need differant sights ,,all info will sure be helpful ,,thanks in advance

To do it right you will need a different slide.

The 45ACP breech face is too big and yes you will need different magazines which will be your biggest problem

I LOVE 38 Supper

But the more that I think about it, the ejector might be wrong and you will probably need to change the locking piece in the 45 donor frame.

I need to grab my 38 Super and compare it to a 45. Fortunately I know right where it is, we shot it less than two weeks ago

A new slide and, when I asked Bruce Gray snit such a project, he thought the locking block was also different. I'm not sure about the ejector.

Such a conversion would require at minimum a dedicated .38 Super breech block, locking insert, barrel, recoil spring and magazine. I suspect you would also have to change the sights for proper regulation. I'm uncertain whether or not the the ejector is caliber specific. To my knowledge, SIG only offers one item number for this part though the attached thread suggests there may be dimensional difference between ejectors of various calibers. It's quite possible that before P220 became synonymous with .45 auto there were multiple part numbers for the ejector assembly.

https://sigforum.com/eve/forum...450053094#5450053094

Numrich may wind up being your friend.

Question: what kind of slide do you already have - the folded over version or the version milled from stainless steel? The folded over version can be converted with the parts hjs157 mentioned, and that should be true for 9mm and .30 Luger as well. The milled version will require gunsmith modification. FWIW, Grayguns has converted at least one milled (220 Match) .45 slide to .38 Super that I know of; the thread where Grayguns showed it off here may still be around if you do a search for it.

Thanks for all the help.The converstion is going to be more than I anticipated,Still gonna try.now the hunt is on for parts

Consider the barrel is a different diameter also. You may be able to weld and drill the slide to the correct diameter.

After all of the time and effort it may take to do the conversion, it may be cheaper to just buy a .38 Super.

It would also be easier if you started out with a P220 in any other caliber.

I know the P226 9mm barrel drops into the P220 .38Super slide and functions reliably- in my tests.

If you have a P220 in .38Super, you can use 9mm for the cost of a barrel, a recoil spring, and patience with the magazines. I wouldn't trust a .38Super mag with 9mm ammo in it for carry/home defense.

But for range swapping, they work ok.


I don't know the dimensions of the P220 .45 barrel diameter at muzzle for comparison- and mine are locked in the safe, behind a sleeping lady [don't mess with momma when she's sleeping].

I am not stating that the barrel outer diameter for .38Super and 9mm are exactly the same- but the 9mm barrel fits/feeds fine in the .38 slide.


I really do enjoy caliber conversions just for the fun of it.

That said, I wouldn't attempt this, as the cost to source all of the parts might run you more than a .38Super p220.

I picked mine up around summer of 2019 or 2020 for about $700. For my neck of the woods, that is pretty good.

I would not be surprised if the proper barrel and completed slide ran you over $500. I would hope for less, but wouldn't be surprised.


Oh, my 1995 P220 .38Super is also an internal extractor- look for a backup P220 .38 or 9mm extractor while you are at it.

I am curious how this turns out.

I personally went the separate P220 route.

Now, in my nicer 1911, I DID set it up to allow me to swap the upper/slidestop/recoilspring/magazine and switch between .45acp and .38super/9mm.

That was a bit hit & miss- and wasn't cost effective- but I am content.

It was easier to convert a Glock 21 to .38 Super than what I can imagine a P220 would need.