MagnaPorting was a proprietary process for cutting ports in rifle and shotgun barrels. Don't know if it is still available. If you drill, ream, or mill into a finished barrel, burrs are thrown up in the bore. With Electron Discharge Machining, the part is submerged in an electrolyte, and a shaped electrode is brought up to it. Because the stock removal process does not involve mechanical cutting, there are no burrs thrown up in the bore. The port can pass right through the rifling without any negative effect on accuracy. MagnaPort used trapezoidal shaped ports in rifle barrels.
The barrel length regulations for longarms refer to barrel length, not rifling length.
You contradict yourself. According the the law, barrel length is the length of the barrel that is rifled, add ons, brakes, etc. don't count. The AR180B-2 is the exception to the rule, because it is all one piece.The barrel length regulations for longarms refer to barrel length, not rifling length.
Barrel add-ons - brakes, compensators, etc. - don't qualify as part of barrel length for legal purposes.
You contradict yourself. According the the law, barrel length is the length of the barrel that is rifled, add ons, brakes, etc. don't count. The AR180B-2 is the exception to the rule, because it is all one piece.




























