A couple years ago, I got a deal on 1,000 rounds of Tula in a mixed lot of 223 and 9mm. With the 9mm rounds in my M&P9FS, I had failure to eject occurring within the first 3 shots on the OEM barrel, and the first round shot from a KKM precision barrel on the same handgun had to be beaten out with a hammer and rod. However, my Sig M11 hummed through 250 rounds of the same ammo without a hitch in the same range session (not 1 failure at all). The 223 ammo cycled at a failure rate of 1 round every 2 magazines fired through a spare Model 1 upper receiver I used on a YHM lower. The ammo shot into reasonable groups, but not consistently enough. About 10% of the rounds strayed well out of group, and half of the strays never hit paper at 25 yards.