Re-boring question black powder rifle or pistol barrels.

[Ugly Sauce]

When, let's say a .50" barrel is rebored to a larger caliber, is the reamer stopped before the breech plug threads?

Am I right to assume so, as then, or if not (barrel bored all the way through) a breech plug with larger diameter threads would be required?

Can the rifling tool then cut rifling without the barrel being bored all the way through?

I'm sure there's a "no duh" answer to this, but I can't quite figure it out.

TIA

 

[Jackrabbit1957]

I would think it could be done either way but I am not a barrel maker so any one else chime in please.

 

[PapaG]

Going from 50 to 54 probably wouldn’t affect the threads. A barrel maker would remove the plug, rebore, and then recut the rifling, probably from breech to muzzle. Direction doesn’t matter but they go all the way.

 

[Ugly Sauce]

So, the threads would be of a (much) larger diameter than the bore. ?

 

[PapaG]

So, the threads would be of a (much) larger diameter than the bore. ?

Should be. Has to be as the bore goes all the way through.

 

[Ugly Sauce]

Okay, thank you, I understand it much better now.

 

[PapaG]

For safety, the thread root would have to be larger than the bore dia. I remember that when I was building muzzle loaders, the thread size for a .45 cal was 5/8-18. The tap drill was way bigger than the .450 groove dia.