The reason I ask is my LGS has a TON of 45 GAP ammo in stock for a decent price and since the dimensions of the 2 rounds are close-ish, I was wondering if anyone made a drop-in conversion for a G21 to accept 45 GAP and if anyone had any luck with it.  I ran a google search as well as a search here to no avail.  





Thanks!



B_E


 

No it wont work.  

45gap runs off a 9/40 frame and mags.

There is no reason why it wouldn't work, that is if an aftermarket barrel was made for the G21 to accept .45 GAP.  You could use G21 mags, but I'm not sure if there would be extractor issues or not since the two cartridges are designed a little different, although the same caliber.  

Call KKM and ask.  If it's been done before they've probably done it.

It might be cheaper to track down a g37.

I'm sort of afraid of that



 

I have a fair amount of GAP ammo and for years I did a lot of shooting with a G21 (Duty gun was a 37).  One day I had my head up my ass and grabbed some GAP ammo and went out back to shoot my 21.  I was nearly 150 rounds into things and I noticed I was shooting GAP ammo out of my 21.  I had no malfunctions.  However, during clean up I did notice that my firing pin was significantly rounded over.  I don't know whether this was due to improper headspacing or just coincidental wear.  







If someone would make a GAP barrel for a 21 I imagine it would work great.  I would not recommend shooting GAP out of an ACP barrel because of excessive headspace issues.  

True story.

I see GAP guns all the time, and they're cheap.