Thanks Mr F. :-)
I think I am going to pull the trigger (so to speak) on a 501. Would prefer to get a 503 (HMR) 1st but no luck yet finding one. Anyone thinking of selling theirs?
Also did the 504 make it into production (HM2 / Mach II) I see the Mark II mags fit 501 & 504 so I would assume the 504 was the Mach II.
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