That Hammerhead is a great tool. I've removed at least one castle nut that I can think of with it that I couldn't previously on a couple other wrenches.
Which reminds me I also have a Starrett spring loaded center punch that does good on staking for the receiver extension nut. I wasn't sure how well it would do when I bought it but I've been quite pleased with the results.
Sig Sauer LE Armorer
Glock LE Armorer
Colt AR15/M16 Armorer
T.O.S.S. (Tactical Officer Survival School) inst. Tom Long
Vicker's Tactical Pistol 1 & 2 Carbine 1 Advanced carbine Inst. Larry Vickers
Intermediate pistol Inst. Ken Hackathorn
Combat Speed Inst. Dave Harrington
Performance Pistol Inst. Frank Proctor
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