Anyway know how to figure out what the final muzzle diameter a barrel would be after its cut to a specific length?
Gunsmithing Calculating Barrel OD before cutting?
- Thread starter lonely_wolf
- Start date
Re: Calculating Barrel OD before cutting?
It's going to depend on the barrel maker's contour/taper. So that info is needed in order to figure out the answer.
It's going to depend on the barrel maker's contour/taper. So that info is needed in order to figure out the answer.
Re: Calculating Barrel OD before cutting?
With what degree of precision? If you're hoping to make parts to mate up with it perfect you can forget it. If you just want to have a good idea (+/- .005" or so):
Calculate how many thousandths of an inch of taper there is per inch of barrel.
Multiply that by how many inches are getting lopped off.
Example:
Bartlein M24/M40 is 1.200" for 3", then tapers to .900" at 26"
26" - 3" = 23" (this is the length of the taper)
1.200" - .900" = .300" (this is the amount of taper)
.300"/23" = .01304"/" (this means the barrel tapers .013" per inch of length)
If you cut 3" off the muzzle:
3" * .013"/" = .039" (this means you'll be cutting off .039" of taper)
.900" + .039" = .939" (new muzzle diameter = original diameter + the amount of removed taper)
Hope that helps.
Bear in mind however, if the smith starts with that same 26" bartlein, and makes shortens it to 23" by chopping 1" off the breech end and 2" off the muzzle end, you'll only be removing 2" of taper (.026" in this case) for a new muzzle diameter of .926".
With what degree of precision? If you're hoping to make parts to mate up with it perfect you can forget it. If you just want to have a good idea (+/- .005" or so):
Calculate how many thousandths of an inch of taper there is per inch of barrel.
Multiply that by how many inches are getting lopped off.
Example:
Bartlein M24/M40 is 1.200" for 3", then tapers to .900" at 26"
26" - 3" = 23" (this is the length of the taper)
1.200" - .900" = .300" (this is the amount of taper)
.300"/23" = .01304"/" (this means the barrel tapers .013" per inch of length)
If you cut 3" off the muzzle:
3" * .013"/" = .039" (this means you'll be cutting off .039" of taper)
.900" + .039" = .939" (new muzzle diameter = original diameter + the amount of removed taper)
Hope that helps.
Bear in mind however, if the smith starts with that same 26" bartlein, and makes shortens it to 23" by chopping 1" off the breech end and 2" off the muzzle end, you'll only be removing 2" of taper (.026" in this case) for a new muzzle diameter of .926".
Re: Calculating Barrel OD before cutting?
@Gaslight: Not if I'm looking at specs on a website.
Thanks Turbo54. That should do!
@Gaslight: Not if I'm looking at specs on a website.
Thanks Turbo54. That should do!
