700 tenon thread diameters

[supercorndogs]

I have a Remage barrel I was just putting on. When I screwed the action almost to the recoil lug I could feel the play up and down in the tenon threads. This action has not been trued, and has burnt out several barrels, as well as having a rotation of three other barrels I switch back and forth on it currently. None of them do this. I just measured the major diameter of the tendon thread and I am getting 1.059-1.060. I don't have ring gauges or micrometer , but when I put my caliper in the groves looking for the minor diameter I get 1.004. I measured both with two different calipers. This is unsafe and I should be returned correct?

The muzzle threads are so big my QD attachment also has to be turned on with wrench from about half way. Again none of my other barrels are like this. This barrel is a replacement for a barrel that the muzzle thread cut way undersized for a 5/8/24. With the muzzle device almost at the shoulder you could wiggle it up and down on the threads.

I don't mean by grabbing the end away from the threads. I mean if you grab it by the shoulder over the threads, you can fell it move up and down. For both.

 

[Supersubes]

Unfortunately you have to take a proper pitch diameter measurement to be sure. The thread play is of course an indicator, you just dont know how much. 1.060 is pretty standard. You dont actually know what the root diameter of any receiver thread is, so its common to remove some off the major dia to ensure clearance with the root of the receiver thread, and then cut the pitch diameter to fit or to a go/no-go pitch gauge.


Gunsmith barrel or off the shelf remage?

 

[supercorndogs]

Custom ordered remage.

I thought it was supposed to be 1.063 minimum major for the thread specs I looked up.

Maybe I just want an easy way to document how bad it is with out buying tools. I might try to get a good picture of them next to some Criterion, and Crown Ridge barrel threads, and see if the difference is noticeable. I didn't think to take any measurements on some other Remage and factory barrels I have sitting. I will say the threads looked fishy and extremely rough to me when I looked at them.

 

[Supersubes]

No, thats maximum. Note how wide the max/min is, but the pitch window is much tighter. If you can get some wires and a micrometer(not a caliper), that would be enough. I can link you to this calculator. Google the “three wire method”

 

[supercorndogs]

Ok i wondered I just measured one of the Criterion barrels and its major 1.054. I think this picture is kind of telling though. You can see it didn't even squeeze and distribute the little glob of antisieze on one of them. Let me check out wire, I know where i can use a mic.

 

[Supersubes]

Whats more telling is the crest of the thread is a point, it should have a small flat just like the barrel on the left.

 

[supercorndogs]

They looked way too sharp to me when i opened it.

Hopefully on the mic anyway. I think he has a 1"-2".

I am sure they can fix it. Not sure I can trust them. This is 0-3.

 

[supercorndogs]

Fail

 

[Supersubes]

This is one I did recently. Exactly 1.060 , and pitch diameter is just small enough to thread into a defiance anTi.

 

[supercorndogs]

Those look nice to my untrained eyes.

The threads on the Criterion and crown ridge barrels look nice to my untrained eyes.

The other one looks like crap to my untrained eyes on both ends.

 

[Supersubes]

New gunsmith? I’d just send it back.

 

[supercorndogs]

McGowen, I ground down the pin on the ar-15 barrel extension myself not a big deal. His CS has been fine but repeated stuff like this gets old.

 

[Terry Cross]

I am sure they can fix it. . . .

Nope.
It is going to wire way (like a lot) under even Class II specs.

No way to add material where it is already undersize so the only way to use that barrel at all is to cut off the abused end, re-chamber and re-thread.

.

 

[Rubicon Precision]

Receivers and muzzle devices aren’t gauges, but it does sound like both ends warrant proper gauging and probably the barrel replaced.

 

[supercorndogs]

Nope.
It is going to wire way (like a lot) under even Class II specs.

No way to add material where it is already undersize so the only way to use that barrel at all is to cut off the abused end, re-chamber and re-thread.

.

I didn't mean actually fix the threads. I meant I am sure he will fix the situation. I doubt there is enough material forward of the threads to chop it and re-thread.

 

[supercorndogs]

Receivers and muzzle devices aren’t gauges, but it does sound like both ends warrant proper gauging and probably the barrel replaced.

I am aware, but you should not be able screw them all the way in and rattle them around like a husky with a hulu hoop.

I can see with my eyes that one thread is at least twice as deep as the other.

 

[celltech]

Had the *exact* same thing happen to me on a barrel I ordered back in '18. Was for a Savage and it did seem loose but I didn't think anything of it...was shooting 1/2" groups right off the bat. Another forum member was having issues with his barrel from the same company doing the same thing and sitting cattywampus in his stock. It made me go pull mine off and get a 3 wire set to measure the root diameter...it was way too small.

Sent it back and they discovered some employee had made several barrels just as crappy. They claimed they fired him and cut me a new stick...

 

[supercorndogs]

The real bummer is the first barrel was stolen at a UPS facility on its way to them, so they have already replaced this barrel once.

I might see if I can get it measured, I don't want to send it back if its just on the small side of spec. I don't think that will be the case.

 

[Rubicon Precision]

If it makes you feel better, (going off memory here) there’s the potential for about .012” of clearance in a class 2 fit between a boy and girl 1-1/16-16 thread, and about .009” for a class 3. Things can feel sloppy, real sloppy, and still be in spec.

But you’ve got plenty of concern to get the threads measured properly. Chances are they are out of spec, especially the muzzle.

 

[supercorndogs]

So if i put a dail indicator on the barrel nut, and could move it up and down more than .012" would that be a pretty good clue?

 

[B'N'F]

No, not really. The barrel nut has nothing to do with fitment between the tenon thread and the receiver thread. Likewise, measuring off of the OD of barrel nut introduces additional tolerances and fit that could (and likely would) give you additional errors in your readings.

 

[supercorndogs]

The female threads in the receiver should be inside the same spec as the threads in the barrel nut.

I am not looking for a method to get an exact measurement, but I want to be almost certain these threads are too small before I complain and ask for a shipping label. At the end of the day, shipping it back myself costs about the same as wires to measure it myself.

Just re-read some posts, kind of mis-read the first part the first time. That makes me pretty certain. I will just send it back.

Thanks @Terry Cross and others who helped

 

[supercorndogs]

So I sent Mcgowen the picture, and his response was.

"You can send it to us and we’ll check the threads again as we typically check them before they leave"

I thought this was pretty rich considering the original barrel went back for undersized muzzle threads. The major diameter was way under. They were the loosest threads I have ever felt, even looser than the tenon threads on this barrel. The muzzle threads on this new barrel, need a wrench to thread the muzzle device to shoulder. Same with my 20 Pratical AR barrel from him. These muzzle devices have been on many other barrels with out the same problem.

That got me looking even closer and thats when I noticed this barrel was not even crowned. The rifling protrudes past the end of muzzle when looking with a jewelers loop. It looked way off center at first, but that is just paint lines.

I am not sure I should even trust them to fix this.