These are printed barrels compatible with CMMG, RTB, and PSA dedicated 22lr AR bolts and Redman's barrel liners. I have not live fire tested these, but have tested for feeding and extraction. Included in the STEP are 4.5, 6, and 9 inch versions. There are also modeled in supports that break away with minimal effort. *** This is an untested design and is posted more as a work in progress for anyone to iterate on *** Updates *7/29/2024 - Added 1/2-28 x 8" Barrel - Added STLs for SG22 and Daichi Barrel Nuts and Extractor Filing Jig - Added Extractor Filing Jig *7/27/2024 - Added 1/2-28 and 5/8-24 muzzle options LBRY Tags: gatalog