I went shooting with a group of seven today. We shot a 510 Kodiak express, 700 AHR, ultralite 500 Jeffery, 500 JRH, and took a 500 A Square Hannibal. The first 4 guns roared often with no problems. I think the ultralite 500 Jeffery, kicked the sharpest of them all. The 500 A Square would not chamber the reloads I had made for it. The bolt would not close with a round in the chamber. I checked the over all length of the cartridge, and it was to spec. When I got back to the house, I took some of the 500 A square brass that I hadn't loaded yet and tried to put a piece of brass only in the chamber, the bolt still wwould not close. My conclusion is that the gun, previously unfired,is either chambered incorrectly,or the factory brass is not to spec. I miked the brass and took about ten different measurements. All the measurements were to spec with the cartridge measurements in "Any shot you want",the A Square book on cartridges. Am I missing something? Could a factory actually put a gun out with the wrong chamber size? I guess I will call A Square Monday morning and see what advice Art has for me. The only other thing that went wrong during the afternoon was that one of my buddies flinched big time while shooting my BFR revolver chambered in Win 50-110. He accidently hit my chronograph and ruined it. So now that has to be worked on or replaced. I guess that gets listed under "shit happens." Over all though, I still enjoyed about 4 hours shooting with the guys, beats working any day of the week, and I got to avoid the shopping crowds with my wife, the day after Thanksgiving.