by Texas Sheepdawg » Wed Nov 16, 2011 1:53 am
From my experience, the 450B functions well with both a rifle and a carbine buffer system. I've shot mine off of 3 different lowers and had no issues. As far as springs' lengths, I really don't know what length without taking one of my rifles down and pulling a spring out to measure. However, I would wait and try the factory mag first.
There is a small mod you can make to a factory mag to make it perform better but I'll need to make a few pics. But if you have laws restricting you to five or less rounds, this mod could get you in trouble. After I did my mod, my mag holds 7!
-Texas Sheepdawg
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