Well, twl has stated that Advanced Barrel Systems uses an MGI QCB upper to accuracy test their barrels, and sub-MOA groups seem to be the norm for them, so I suppose there's little to no practical difference in accuracy.
It should have the potential for more accuracy-it's free-floated. I'm using one of the older MGI models as a basis for a RECCE. Make sure the barrels you buy for it come without the barrel nut and delta ring-you want them totally stripped behind the gas block.
Originally Posted By whoanelly: It should have the potential for more accuracy-it's free-floated. I'm using one of the older MGI models as a basis for a RECCE. Make sure the barrels you buy for it come without the barrel nut and delta ring-you want them totally stripped behind the gas block.
Don't most barrels come standard with a barrel nut, and why would it be a problem? Can't you just slip it off.
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