man i thought those specs in the letter sounde familiar mine was made september 7 1891 45/90 caliber octagon barrel converted to 45-70 octagon heavy barrel plain trigger 1/2 mag serial #606xx maybe we have brothers!! and i do shoot it! wish i could post picts.
Bleated congrats on the letter! Moreover, congrats on a nice 1886 in any context! These Browning masterful design veterans, century+quarter later, still viable and emulated in new production!!! What kind of a record is that as well; another feather in John M's cap!
Yours, a gun to be proud of! Factory new barrel and functionally "improved" as moving to newer/stronger "Smokeless" barrel steel! Sad in context of moved to a nowadays (wrongfully - my opinion) obsolete chambering. The .33 Win a respectable cartridge and better as all round heavier chambering performer than some of the 'lingering lot' of 'also rans'! Ironically, my prior conjuring of shooting these 'but for ammo prices', in context of custom stuff available. Nowadays, just about everything with availability issues as yet often second of pricing! Such the nowadays 'but for' shooting factor!
I'm with several original1886 models, from 1903, 1905 & 1920 manufacture; takedown, solid frame and solid-full mag, respectively. All in .33 Winchester. Two of which in the same configuration resembling yours and other as noted magazine. All 3 with 24" barrels. My appreciation for the '86 design reflected in also acquiring a Browning '86 Carbine, Miroku faithful reproduction, product of the early nineties. Also a Winchester current production '86 with the 'ugh', but somewhat acceptable tang safety. So here, much verbiage to say the short of it; a Model 1886 fan if simply overshadowed by 'pre 64 Models 70 & Models 54; so many & so little time! Incidentally, if you didn't know, your rifle year of 1891, year production of 13,877 rifles alleged.
My three originals, quik pix below. Best & Stay Safe! John