I know the Seekins, Burris XTR & Talley are aluminum. I believe the others are steel.
Talley claims these are billet. From Talley:
"Heavy-duty scope rings are precision-machined from solid billet aluminum with dual recoil lugs to ensure your tactical scope won’t budge under the heaviest recoil. Full-width ring caps are cut from the same billet as the bottom half of the ring for precise fit and held in place with four stainless steel Allen head screws that won’t work loose when properly tightened."

I know the Seekins, Burris XTR & Talley are aluminum. I believe the others are steel.
Talley claims these are billet. From Talley:
"Heavy-duty scope rings are precision-machined from solid billet aluminum with dual recoil lugs to ensure your tactical scope won’t budge under the heaviest recoil. Full-width ring caps are cut from the same billet as the bottom half of the ring for precise fit and held in place with four stainless steel Allen head screws that won’t work loose when properly tightened." Something ain't right about the information they put out. Cutting them from the same billet wouldn't have anything to do strength, as the compressive strength of any grade of aluminum wouldn't vary from billet to billet. If these are true Ø's and made as a single piece and then split, that may contribute to the fit, but then they would be made as oval to allow for the kerf when cut. Also, using a stainless steel fastener, in cast aluminum gives a mismatch on the strength characteristic; the fastener can handle a > torque. I've never bought these, but would have. I may have missed it, but have we not agreed that these are cast, but sold as machined from billet stock?

55-65 in-lbs is a fair bit when talking about aluminum threads. I've stripped aluminum threads when tightening down a valve cover with about that much torque.

At least they're sending you a pair of black ones for now.

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