Quote Originally Posted by MarkCO View Post
I tried several different configurations with .223 and eventually came to the conclusion that the .223 in a short barrel was not optimum for anything. Sure, it can be done, and I got them to run, but I am much more pleased with the 300BO upper in terms of shootability and performance. I can ring gongs at 200m 1 for 1 and it works great for close stuff too. Runs from 110s to 240s with less muzzle blast and less stress (and wear) on the BCG and upper receiver. If you are sold on .223, I found that moderate 77s worked the best, but still pretty punchy. I would go with 10-12" over a 7 or 9" based on my experience. I'd go with a Noveske Pig (or just a thread protector) over a comp myself. You could go retro and try and find a Vietnam Era Colt conical. That is bascially what the Noveske Pig is anyway.

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I have read with the short barrels you generally want to run light/fast rounds like the 50gr stuff so you get that fragmentation??