12 ga upper for M-11/9 project

[rybread]

Still grinding away, making progress during vacation between other things. Still a ways to go- waiting for our community shop to open back up after the new year and get on a regular schedule. I’ll submit dimensions for the dummy bolt. This is simply a 1x1x12 wood block, cut to bolt profile to ensure proper alignment of parts as they’re assembled. This is another challenging part but I’m taking it one step at a time and making sure it’s right before proceeding.

[mwarnick1]

Thanks for the update. I’d been wondering how you were doing.

[rybread]

It’s good to be busy!

[rybread]

All right guys sorry for the delays I‘ve been busy with other projects. The specs for the welding jig have been submitted and accepted. Should have it by EOW. This will guide the final grinding detail and welding to attach the Mac upper assembly in place. Nearing the last mile and pushing hard to get this to the range when it warms up!

[rybread]

Part finished. Will pick it up tomorrow and get to work!

[theduke]

Git busy......I'm quite curious how this is shaping up.

[rybread]

Important piece completed. This is a “ghost” of the “bolt travel” inside the upper, to act as a welding jig- this will ensure perfect alignment as the parts are fitted & welded together. Made from MDF (medium density fiberboard) instead of pine, as it will be more heat resistant.

[rybread]

3D test bolt profile- beside the welding fixture.

[rybread]

Mac upper, prepped to weld the top mount on!