NAA Rare Big Bore: 450 Magnum Express
Not a lot of folks know that back in the 1970s, NAA was sort of a precursor to Freedom Arms. Dick Casull had them make some of his earliest 454 Casull revolvers.
North American Arms built their own big bore single action on a unique large frame, designed around their proprietary cartridge, the 450 Magnum Express.
This cartridge was a lengthened version of the 45 Winchester Magnum, itself most often encountered in the Wildey gas operated semiauto pistol.
Like Freedom Arms revolvers, the 450 Magnum Express was built using 17-4ph stainless steel. It differed in important ways from the Ruger Super Blackhawk (to avoid patent infringement?), such using a sliding transfer bar safety and flat springs.
The standard grips were walnut with an integral filler behind the trigger guard, arguably a more effective way to mitigate recoil than found with Rugers, Freedom Arms, Sevilles, etc.
Because of the rarity of 450 Magnum Express ammo and brass (made by Winchester) most NAA revolvers were sold with an optional 45 Win Mag cylinder or, in rare cases, a 45 Colt cylinder.
One problem with the project was the rimless design of the 450 cartridge, resulting in the necessary compromise between an effective crimp and positive headspacing.
Most NAA 450s were finished in a very nice high polish.