Quote Originally Posted by NeiljohnUK View Post
Ugly threads, even when done by a competent smith, are the bane of many long-guns, I have a knurled cover on one my father had done, it also meant no fore-sight remained so scopes only now, which with the factory rail are a royal PITA. I was looking at moderators (we don't call them suppressors or silencers as it frightens people) for a Mod.70, everyone needed threading of the barrel thus ugly and reproofing needed too. One day I may investigate a collet clamping system in a long sleeve back over the barrel for the collet clamping, with a precision guide ring over the muzzle, but I've more important jobs to do for now so it's a sometime never round-tuit for now.
For the past year now, I have been putting together a selection of 20TPI 28TPI 32, 36 and 40 TPI taps and dies for my work in hydraulics, I have done a few barrels for a couple of friends who do competition shooting, even though I prefer to single point thread a barrel I like to make the final few thousandths with a die. Many barrels are too thin at the end to accept a very coarse thread not that I would ever recommend a coarse thread on a barrel for any reason. To me coarse on the end of a gun barrel means any thread of 20TPI of fewer, 28 TPI seems to be an accepted thread pitch by a few smiths I have talked to but if someone desires to have a modified or full choke added to their 12,16,20, 28, or .410 ga shot gun most of those barrels are way too thin for 28 TPI but 32 or even 40 TPI in some cases will leave 75% of the barrel thickness. The threads must be proportionately longer but the trueness to the center bore is amazingly easier to maintain.