As an update, I have "revisited" the Buffalo Bore 220 gr Hard Cast loads after switching to the Glock 6" barrel, 22# recoil spring, and stainless guide rod. No problems at all, pistol loads and cycles as it is supposed to, fires without incident, and is accurate. I have not yet had the opportunity to shoot the Double Tap 200gr Hard Cast and Nosler JHP loads, but expect no problems with them, either. While 10mm recoil is not excessive, the heavier spring and rod DO make a difference. I am now much happier with the Glock - maybe one day I'll like it as much as it's legions of avid followers do? Still prefer my 1911, but for a semi-auto hunting handgun, I think this one will do fine.
