Who is or have made a bolt from it?
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It was long suspected LMT and KAC were using Aermet 100 for their bolts. Apparently this new Ferrium M54 is being used as a direct replacement for Aermet 100 in the aircraft industry these days which also might explain the electroless nickel finish switching to chrome plating recently.
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Anyway the point Im trying to make is that after deep diving into the world of bolt steels to find out why I can't have a $70 uber bolt this is what I found. This Aermet 100/ Ferrium M54 stuff that E-Bolts and E3 bolts are made of are crazy expensive and very limited in their production which is why you can't uber bolts any cheaper.
I've never bought a crappy bolt, and I've never had one break. Only ever seen gas rings broken.
Vanadium modified 4330 is the steel all your modern US Navy aircraft* tail-hooks are made from, with the exception of the old F-4 Phantom, that required a Inconel hook as it resided right in the exhaust wash of two J-79s . . .
M54 is actually only used on one type/Model/Series, the T45. And, it is not used in the hook, but the hook shank. The Navy seems to have bought 60 of them.
I don't think you're going to like bolts made from your "uber-steel". In order the get those high material properties they are working in a HRc range of 52 to 54. Carpenter 158 and 9310 bolts are surface hardened to low 60s for wear.
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* F-35 Lightning, C-2 Greyhound, E-2 Hawkeye, EA-6B Prowler, A-6 Intruder, F/A-18C/D Hornet, F/A-18E/F/G Super Hornet/Growler, A-4 Skyhawk, and S-3 Viking.
So whats the current uber bolt steel if its not Aermet 100 or M54?
I've broken 1 bolt in an ar and have seen a few go down. Usually in a short suppressed postie. A friend broke a psa bolt in one but it was thousands of rounds in. Mine was a colt bolt in a 10.5 suppressed gun, I've seen a bcm bolt go down as well.
Last bolt I broke was sadly not in an ar style gun. I broke a hk21 bolt in my K gun(10.5 inch 308). Short full auto 308 though with god knows how many rounds through it. I know the gun was run pretty hard before I got it.
There are three major properties a steel used for a bolt needs:
1) High strength
2) High toughness
3) High surface hardness
Just because a steel has a yield strength of 300,000 psi does not automatically means it will be a good steel for a bolt if it achieves this strength at a hardness of HRc 48-52.
Actually, the best steels for bolts are the same steels used for gears. If you want a new 'superalloy' for bolts you might want to look into Ferrium C61® or C64® steel.
I always enjoy reading your posts Lysander. Thank you for contributing.
No clue. I've personally never broken one in 25 years of shooting.