OK the .35, .30-30, and .444 are all 0.650" on the outside diameter. I suppose it isn't too critical as long as the cartridge will fit in it.... would imagine that the .45-70 and probably .450 Marlin tubes are larger.
Probably the most critical dimension is the recess in the front of the receiver that the mag tube fits into.
A forum community dedicated to Sport shooters, owners and enthusiasts. Come join the discussion about optics, hand casting bullets, hunting, gunsmithing, styles, reviews, accessories, classifieds, and more!