Adjustable arm brace for the AR15. This allows improved handling and stability on AR15 pistols, and mounts directly to a Commercial-spec carbine extension tube. Extends and collapses to however many positions are available on your tube, and requires no mods. Latch is also included; you need to source your own spring, plunger, roll pin, and nut.
Included are 2 designs: 'Open' which has the hole through the full length of the brace, and 'Filled' which has the hole filled at the back end. The 'Test' file should be printed first to confirm fit on your extension tube. A one-piece file is provided if your print bed can handle the full size, and a 2-piece set are also provided to allow printing vertically on a bed that doesn't have the full Z-range.
Full CAD files are provided, please feel free to adjust to your needs and style.
Disclaimer: This is for a PISTOL AND/OR AIRSOFT ONLY. This is NOT A STOCK, and is designed NOT TO BE SHOULDERED. DO NOT REDESIGN AS A STOCK. Follow all BATFE and NFA rules and regulations at all times. ATF guidance is included for your reference, please print and use responsibly and legally.
I printed the 2-piece set vertically in PLA and with 'everywhere' supports. Depending on your slicer, it may orient it at a slight angle; check the very bottom to make sure you don't have a couple layers of support or partial profile. If you do, just drop the model 1mm below your Z-zero plane and it will print fine.
205°C Head, 50°C Bed, Fan 100%
50mm/s inner wall, 25mm/s out wall speed, 5 layers all around
Post was easy, supports come right off. I mounted both pieces on an extension tube, and bonded with CA. I didn't need to touch the inside of the hole at all, just worked it back and forth a few times to break off the edge and allow smooth travel.