hammeredsole

I’m still interested. I don’t think the m4 community is as beholden to Titanium per se, rather that they prefer exotic materials. Most aftermarket stuff is 6000 series junk. Lithium AL and 7000 series is a totally different ball park. Obviously, ti works better in a tube, but imho quality billet makes more sense for chunky parts like a cap or mag button, trigger housing, etc.. I think you’d have better uptake on a ~$75 aluminum cap than a $100+ ti item. Only issue could be bimetallic corrosion on ti tubes, which would be a further selling point on your 4130 tube. not sharp shooting you here, just a different perspective. I have extensive materials experience, but little manufacturing experience.

Why not go with 2055/2099 or 7000 series aluminum? Much easier to machine, lighter, and nearly as strong as titanium. At the very least, much tougher than factory FRN.