Sidearms & Scatterguns Glock 21 -20 conversion

acts238

Sergeant
Full Member
Minuteman
Mar 2, 2011
762
19
66
N W Montana
I've been looking for a 10mm conversion barrel for my 21
Can't seem to find any
If you know a source please post it
While I was polishing several Glocks last night for a friend and noticed that the 20 barrel fit perfectly in the 21 and vice versa - the ID diameter if the hole in the slide and the OD of the barrels seems to be the same on both
Has any one tried shooting a 20 barrel in a 21 ?
I don't see why it wouldn't work
 
I was given to understand that converting either of the large frame Glocks to the other caliber required a corresponding slide (See note next to G20/G21 slides: Lone Wolf Distributors - Products - Slides), but if you're saying that the barrels are interchangeable... have you simply fitted them together, or have you measured the barrel OD and the slide "barrel hole" ID of each gun to confirm sizing?

If this actually works, it could be pretty interesting...
 
The chamber hood on the factory G20 barrel is thinner so it won't work correctly with a factory 21 slide, you'll need a conversion barrel. The recoil spring is the same. You can either swap the extractor back and forth or modify the G21 extractor so it will work with both the .40 and .45 cal. If you use your "Google Fu" you'll find quite a little info on it. I bought a Storm Lake conversion barrel and G20 extractor for mine but then a member here had a new G20 barrel and top end for sale so I just grabbed it and just swap the whole deal back and forth. Obviously you'll need G20 mags.
 
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Here is a photo of my Glock 30 with a BarSto 10mm conversion barrel, shoots really well. I like the KKM barrels and have a few but got the BarSto at a great price. LoneWolf or the Glock store should have everything you need.
 

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