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FWIW, I learned how to take apart & service my B78's because I thought to purchase a Field Service Manual from Browning.
The early (1970's) B78's have both a easily-adjustable trigger (IF you have made the correct 2-pronged tool from a small screwdriver), AND an external hammer - the M1885 was simply an upgraded/improved B78, with a different, non-externally-adjustable trigger & heavier barrels.
The NEW B78's, OTOH, have shorter bbls than the originals ( 24" v 26" ), and are just renamed M1885's.
I owned several older B78's, when they were first introduced, and can tell you their tapered octagonal bbls were a joy both to shoot & behold. (The .45-70's had a straight octagon 24"bb w/iron sights, though)
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