No one has a Anvil-30 ARC currently so no one has one that is adjustable outside of a few testers. All traditional arca-type/style clamps are friction clamps. If you put enough force on it, itll slip. For extended firing we put satefy stops on our rails to act as recoil lugs to place the bipod against. Our new SC-ARC clamp and Anvil-30 ARC now have a indexing pin so that cant happen along with some other rails and clamps out there namely Area419 as in this post. Area419 arca-lock is made with the RRS 1.5" spec although they did remove surface area while adding in that feature so loss of the contact pads may be a result of it.
OP best things I can tell you:
1. If you believe everything from all companies is in spec, put a piece of gaffers tape on one side of the rail where you clamp in, you may have to trim it to be very small! That should lock it up probably uncomfortably tight.
2. If you feel something is out of spec send it in to us or AREA419. We have a clamp gauges for clamping pressure and they (did, cant speak for daily operation) use our go no-go gauges for their rails.
