First ever build was the Spectre SI15. Build guide said to melt a brass threaded insert into the lower. That way the pistol grip would be screwed into metal instead of plastic.
Reading the Ubar3 guide, Ivan chose to tap threads into the lower. I trust Ivan’s judgement because he’s been polishing the ubar for 10ish years. In my mind though… the brass threaded insert seems like it’d be stronger since it’s metal on metal. Harder to strip out the threads etc.
Thing is… with Ivan’s method you can use the actual screw that’s meant for the pistol grip. If you use the threaded brass insert. It’s a much smaller flanged screw. I’m not sure what to think.
Would appreciate thoughts/advice.
I yolo an M6 into the hole. But we should all do what the Alloy(?) does and have a captive M5 nut instead of a heat-set insert or raw plastic tapping.
Realistically, any approach works, but the more you try to muscle a solution, the more you’re gonna stress the plastic in one of the weakest areas of the AR-15 lower receiver.
Yea that makes sense to me. I printed a bunch of test fins and practiced tapping them. Surprisingly worked well. Still seems like metal on metal would be stronger to me. Recent picked up sets of m4/m5/m6 screws/nuts so I can play around with which one fits best while removing the least amount of material.