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11/24/2012 6:55:43 PM EDT
Is it possible to rethread a barrel to a different thread pitch without cutting the barrel?  Id like to go from 5/8x24 to 3/4x24 (KAC thread pitch) without losing any barrel length.
11/24/2012 7:17:29 PM EDT
[#1]
Generally, no, unless reducing to a new major diameter smaller than the old minor diam. A big increase in minor diam can be handled with a threaded sleeve which itself gets threaded.

Sometimes the old threading can be turned down, a sleeve pressfit on, and new threads cut in the sleeve.
11/24/2012 7:34:32 PM EDT
[#2]
not in this case
11/24/2012 7:36:31 PM EDT
[#3]
Thanks for the replies, looks like Im going to 15.5" and a pin.
11/24/2012 7:42:37 PM EDT
[#4]
Both of those threads that you are referring to, have a pitch of .0417"
Are you sure you want to change the pitch?

It is really hard to make an external thread bigger, ie going from 5/8" (.625") to a 3/4" (.750")

Are you sure you are measuring them right?
11/24/2012 7:55:13 PM EDT
[#5]
Thats whats listed in their catalog.  Im sending Adco a email in the morning to see what they say, Ill send the flash hider with the barrel o they can figure it out.
11/24/2012 8:11:20 PM EDT
[#6]
Quoted:
 Id like to go from 5/8x24 to 3/4x24 (KAC thread pitch)


You know that saying "It's easy to cut things smaller, but it's really tough to make them bigger"....?
11/24/2012 9:30:14 PM EDT
[#7]
Quoted:
Quoted:
 Id like to go from 5/8x24 to 3/4x24 (KAC thread pitch)


You know that saying "It's easy to cut things smaller, but it's really tough to make them bigger"....?


I realized my blonde moment already.  I'm thinking pressed on sleeve and threading it is the way to go.
11/27/2012 7:40:00 PM EDT
[#8]
If it's already threaded 5/8-24 and you want 3/4-24, just have an adapter made.  Basically a barrel thread protector that is threaded on the outside 3/4-24.  Not really that big of a deal.  If you want it to be permanent, sweat in a dab of silver solder and you're done.  If the 5/8-24 internal thread is turned to match your barrels current threads, it will be very concentric, probably within a few thousandths.  If it's just going to be a tapped hole, then have your smith drill and tap a piece of stock 5/8-24 that is .875 outside diameter, silver solder it, then indicate the barrel in and turn the new 3/4 threads on.

Personally I'd lose the what, .750" of barrel length, rethread and recrown, but maybe it's a 16.1" barrel and you don't have that option.
11/30/2012 4:19:29 AM EDT
[#9]
Quoted:
Personally I'd lose the what, .750" of barrel length, rethread and recrown, but maybe it's a 16.1" barrel and you don't have that option.


It sounds like that is the case here (he mentioned he may have to go down to 15.5" inch for a re-thread and then pin the flash-hider on).
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