G22 .40 is the full size partner of your G31 .357 Sig. :thumbsup:

 

I'm running the opposite conversion, a G31 barrel in my G22/gen4. The original caliber mags will work OK, but replacing the mag followers ($2-$3 each) with the right caliber ones makes them identical, except for the writing on the outside.

 

Thank you gentleman for the answer. I see that factory replacement barrels aren't being given away on ebay. So maybe I'll post a want to buy in the WTB section and see if someone has one for a reasonable price that they might let go that is used.

Hartmn

 

The Glock part number for the G22 barrel that you need is SP 04452.

In addition to the issue of the significantly different magazine followers (which I solve by buying new magazines for the new caliber), there are some other things that differ between a G31 .357SIG and a G22 .40SW:

1. If the pistol is Gen4, the ejector that is part of the trigger mechanism housing (TMH) differs. The .40SW Gen4 Glocks use TMH 28927 which comes with the 28926 ejector. The .357SIG Gen4 Glocks use TMH 30561 which comes with the 30499 ejector. But...if you have a Gen4 G31 that does not have 30499 stamped on the ejector, then you have an earlier Gen4 G31 that uses the same (but likely unmarked) TMH/Ejector that the Gen4 G22 uses (it was made before Glock decided they needed to be different). If you have a non-Gen4 G31, ignore this...both .40SW and .357SIG non-Gen4 pistols use the same TMH with 1882 ejector.

2. The rear sight elevation used on factory-installed G31 fixed sights is 6.9mm (short dash above long dash on right). For the G22 it is 6.5mm (long dash on right).

 

You can also buy aftermarket barrels to convert your 31. Lone wolf, stormlake, and KKM are just a few of the more popular brands. A factory barrel is an easy drop in, but so are most of the other brands.

Keep in mind a factory barrel direct from glock is $125. So base your purchase on that figure.