I have a .223 24" bull barrel, no threads, spiral fluted stainless steel barrel, that used to be one of my most accurate rifles I have. I brought it out the other day, and I was barely able to put ten rounds in an eight inch spread at a hundred yards, very unlike this rifle. I was thinking maybe the ammo? Then when I reloaded the rounds because I keep them all separate for each rifle now, I noticed that the brass above the shoulder was too open for the .224 dia. 55 grain bullets I had, so I had to first close it down with my crimper, and then after I reloaded them, crimp them a second time. Since they were all from this rifle, do you think the chamber was cut too big, causing them to expand beyond where they would no longer hold a .223 bullet when reloading? Or it's burned out? There have been about 1000 or more rounds through this rifle, not so many to so quickly, in one range trip, cause it to suddenly burn out I thought. It's either that, or the scope died. Any experiences on this kind of thing?