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will Ruger use the old square style threads or the new v thread on all there new marlin336 barrels and receivers . Might be smart but I may want to replace a short barrel with a 24in barrel. I have 3 rifles here that were 35 remington they all have the 20 in. barrels I would like to replace one with the 24 in. and balard rifling and a full length magazine tub .. sure would be nice to just screw one on .. and being I already reload for 375raptor might be nice to have a 375 caliber barrel to play with .. I would have to make da m n sure I kept the ammo separate by using only nickel casings for the raptor 336..
 

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The Hog Whisperer (Administrator)
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Nobody in their right mind would do square threads on purpose. Too difficult (slow) and tedious to machine. Makes the tooling cost more too. Even Marlin had already gone to 'V' threads for the .450 Marlin - stronger too.
 

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Square threads are easier to index and stronger for their diameter than Vee form. Commercially, they're always milled instead of lathe-made. PITA is very true unless you're a factory set up to do thousands of them.
Square threads means the receiver ring and barrel stub is in pure tension at firing. There is no outward camming of the receiver ring which means it can be thinner in cross section. There is no 'swell' to it under firing pressure so rifles can be made lighter. At least that was the theories set forward by the military. Many styles were tried and some are even worse to deal with. I think its the Danish Krag that has left hand, half pitch, acme barrel shank threads.
I just hope Ruger threads them! The latest craze by the factories is to join barrels with permanent joints. They're cheaper that way.
 

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The Shadow (Moderator)
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Square threads are easier to index and stronger for their diameter than Vee form.
.......Ehhhhhh, no. Whitworth, or Vee form threads Are much stronger than square threads. This is why they are used in all frictional fastening applications. Square threads have less friction, thus more efficient for power transmission applications. You've never pulled any heavy industry fastener that has an insane torque spec(Locomotive engine, mining equipment, etc) and found square threads.
 

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I was repeating what the Ordinance Dept. said in adopting them for the '03. Industrial threads have a much larger nut or threaded cross-section than a hardened rifle receiver. The goal was to prevent radial breakage from expansion. All the forces are in line with the bore instead of spread out at 30 deg. angle.
 

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The Hog Whisperer (Administrator)
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V threads, the receiver can support the radial expansion of the barrel under the threads. Square threads, this is not possible without some insanely tight tolerances. The receiver 'squeezing' the barrel shank makes it stronger as far as radial expansion, much like 'hooped up' artillery tubes.

Yes, Marlin (usually) gets away with very thin receiver threads .... which, with large diameter (ie. .45-70), is pretty much the first thing to let loose with an over-pressure incident. They let go at the bottom of the receiver threads, when the hot-rodding gets too much.
 
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