Figgered I'd start a separate review. Will get to the range tomorrow. Hopefully some video from that but for now, the GCI .50 GI Glock conversion arrived with 60 rounds of fresh ammo. My initial impressions are good and the gun assembles quick and easy, simply put on the barrel/slide assembly, insert a loaded mag of .50 GI and drop the slide. Ready to go. Dry, the new upper assembly passes all function checks. Range tomorrow. The package... The Ammo....(reload data for bullets 180 to about 350g weight is provided with the gun. Brass/dies available from GCI. The oft vaunted 45 ACP, a personal favorite and this one is my carry load of 230g Federal Hydrashok, flanked by a pair of 50 GI rounds capped with 275g hollow points. Inside the box, a slide/barrel assembly with steel guide rod and spring and a 50GI magazine with extension to hold 9 rounds in the mag. Stainless slide. Like the Glock slide, not a single machine mark on it. Both Glock and GCI finish work is exquisite. Inside the slide, all seems to be perfection. Three of the four components needed to convert a Glock 20/21 to .50 GI. Inside the barrel, conventional button rifling. Good for jacketed or lead bullets. I suspect I'll be trying the 255g or heavier lead bullets soon. Wad cutters will be wonderful for hunting. For the time being, the platform will be this every day normal Glock 21 Gen 2.5 45 ACP. Should I like the 50 GI well enough, I may well purchase a dedicated frame for it later next year.