Dedicated 1/2-28 Or 1/2x36 Threading For M-11 Or Mac-10

Send us your barreled upper, we remove the barrel from your upper receiver, reduce the length of the barrel, index down the 3/4x10 threads and re thread the remaining barrel in only 1/2x28 or 1/2x36 . You pay return shipping as well as shipping it to us. Please call with any questions. tell us in the comments section of the order which threads you want, 1/2x28 or 1/2x36.