Host platforms for the 38 Super are somewhat limited, being 1911 variants, or else Sig P220, Taurus PT38 and CZs.  The first category is expensive if double stack and single stack is not attractive to me.  The second category is either single stack (the Sig and Taurus) or else not my cup of tea (the CZ).  So that makes for slim pick'ns.

So here's my thought: 38 Super fits in 10mm mags .. (like 9mm fits in 40S&W mags), and the 10mm platforms are the 1911 (once again), the S&W (single stack ), the Witness (not a bad gun, my first handgun was a Witness but just not my favorite) and the good old Glock.  I carried a G27 for years so no issues there, even have the old leather goods still.

So perhaps I can fit 38 Super in the G20 mags.  But then I need the right top end.

Idea 1 - take the mags and try to fit them in something like the G17 or G34.  Don't have a mag handy so I can't try ...

Idea 2 - the mag from the G20 doesn't fit the G17 or G34, will the slide from the G17 or G34 fit on the frame of the G20 (I doubt it).  Reason is that I need the proper bolt face and extractor for the 38 Super.

Anyone here ever try?  Have any ideas?  I would think I could take the 9mm barrel and rechamber it to 38 Super and that this might be a do-able project.

Or am I once again seriously "confused"

Magazines for the Glock 20 and 21 will fit in the 29 and 30 but no others. They are too wide. So you can't use them in a 9mm or .40 frame.

The slides will not interchange either.

Sorry.

Only way I can see doing this is on one of the "big" frames (10mm and .45) due to the length of the cartridge.  Maybe you could get the barrel made custom, and a slide.  Sounds too expensive.  Might as well go double stack 1911.

Only way I can think of to do it would be to get a G20 and have a .38 Super barrel made for it - rim of the rimmed .38 Super is pretty close to that of the rimless 10MM, so the breechface and extractor should work just fine.

There have been a couple of people that have converted G20 or G29 to 9x23 using Barsto barrels.  Its been awhile since I saw this on one of the other forums, but I believe the pistols were very reliable after the conversion with just a little tweaking to the mags.  

Try doing a search here or here.