I think my 460 Rowland has Kimber has a 25 lb recoil spring w/ comp. The recoil is stout but manageable. I went to 255 gr RNFP bullets and push almost 1400 FPS at the muzzle. You need to trim brass just a bit to properly fit the magazines. I had no problems feeding factory ammo or Hornady XTP reloads. When I went to the RNFP hard cast I would get a miss-feed every other magazine; bullet has a larger meplat. There was a few thousandths edge between the feed ramp and barrel lug that needed smoothed out; feed ramp polish. Mention since it is one of those normal progressions you go through w/ this round; ball to RNFPs. I'd check the weight of the Glock compared to an all metal 1911; lighter gun more recoil. Overall a very positive experience w/ the round and gun.Sounds nice was thinking about buying a Glock 21 and doing the conversion but I do have a Kimber