Cutting threads

Clark

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Oct 19, 2006
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756
It looked good until I saw the pictures. Now I see tearing.
 

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MW204

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I use an indexable carbide insert, lots of cutting oil, no setup for fluid, small increments, and my threads look pretty good when I'm finished imo. My two cents anyway but it is free.
 

tobnpr

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May 30, 2013
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Meh...matters not. Ain't gonna affect how it shoots.
So you're doing a 6.5 Vostok, huh?
That's on my list- I got the reamer print from Manson but haven't pulled the trigger on it because I'm not clear how I'd neck that 54R brass down. Not much shoulder on that barrel, is that one of the receivers with the inner torque ring? Savage take-off?
I think that's one bad-*** round. I've never found ballistic charts on it- but I see it being right there with the .260 on paper.

Details, please !! :)
 

Coyote Shadow Tracker

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It looked good until I saw the pictures. Now I see tearing.
Well I usually don't post on things like this, because there are soo many to respond.
First we need to know what you level of machining is?
What machine and tooling you are using, what speed?
Are you using HHS tooling at what speeded: 75rpm<
What lubricant's did you use?
I suggest that you use a HHS steel tool (not carbide) and "VIPER VENOM" cutting oil.
 

shortgrass

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Mar 31, 2010
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Sure, it'll work as it is. But there used to be such a thing as "Pride in Workmanship", and maybe that's what he's looking for. My guess here (and it's just a guess) is carbide tooling that is being run too slowly. Run any tool too slow and it begins to 'tear' instead of 'cut'. Any machine shop I have worked in would 'reject' that thread finish.
 

RuninL8

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Feb 20, 2019
Messages
37
Location
Columbia, mo
Ok, so yeah surface finish is not great, my worry is that the top of your threads are not filed, which most likely means that when you fit the reciever to the barrel the bearing surface is the top of the v in the threads instead of the back side of the threads. If you filed and fit disregard. However be advised if you didn't, you may only have a few thou of metal for a mating surface. Could be dangerous/will not produce repeatable results.
 

RuninL8

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Feb 20, 2019
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Location
Columbia, mo
I'm sorry, as far as surface finish, if you are using carbide and you are turning slower that 115 rpm. You have to take less than .002 passes with oil. Makes for alot of passes but it will work and give a better finish. Now, if that was with HSS then, you took too big of a cut (more than .003) or your machine needs adjustment, which could be a number of things. Happy to answer questions via pm.
 
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