Shallow action threads?

[shortgrass]

Thank you Edd, that was my plan, HOWEVER, I was bored and thought I'd test fit it again with some shooters choice grease... Ended up being able to tighten it a tad bit more with a bit of force just with my hands and it contacted the go gauge!!! The nogo gauge doesn't allow the bolt to close and it will close on the go gauge without resistance!!!

Now I'll be taking my action and pinned lug to my gunsmith to have a recess drilled into the action. Jim at NSS suggested having the recess 1 thou wider and 4 thou deeper than the lug pin. Sometime down the road I'll probably have the rest of the action trued if i think it will help accuracy, as well as the threads tapped with the standard 1-1/16x16 tap so prefits will work, but hopefully that will take out that small taper at the end of the action threads, allowing an easier headspace job.


I appreciate all the advice from everyone, but understand this is not a standard conventional rebarreling. I am not going to alter the barrel. Barrels are disposable after being shot out and need to be replaced. Id rather alter the action threads minorly, than have to alter each and every barrel I order and put on this action in the future!!

Ryan

What makes you think the next barrel will be exactly like this one? Did you take the original barrel off? Was it OK? I am much more inclined to think it's the barrel tenon, not the receiver. Remington wouldn't have "jacked around" with two parts that wouldn't immediately screw together, they'd have been laid aside and examined later. This sudden and massive surge of installing a barrel with a barrel nut means production of those barrels has been at a 'push', by many different companies, to supply the demand for them. Each company establishing their own tolerances and standards. I'm sorry, I gotta' say it's the barrel, not the receiver. Been working with this stuff too long to think otherwise. Not that Remington can't make mistakes, but those barrel makers can, too. Neither one are perfect, by any stretch of the imagination. I guess I look at this differently because I didn't learn on my own or by watching YouTube videos.

 

[Pdvdh]

More than likely, one or the other has out-of-spec threads, unless you're one unlucky guy.

I'd figure out which is faulty before I started modifying threads. Or you could end up with two sets of threads - both bad.

Time for the gunsmith. Then decide after inspection.

 

[Trickymissfit]

A barrel should be 'fit' to an action, not the other way around. Sounds to me like it's an 'older' 700 action that was threaded during manufacture with a tap, not single point threaded on a CNC turning/machining center, as they are now. In this case, alter the barrel, not the receiver. Chit happens, "drop-in" ain't always "drop-in"! If you try to alter the receiver I can just about guarantee you'll end up with sloppier threads than you have now, unless you buy a 1 1/16" 'bottoming' tap and then all bets are off!

1.06-16 tpi is a standard off the shelf item (still not cheap). Find a bottoming tap, and run it thru the action. If the tap feels loose, place a strip of .001" brass shim stock on one thread flute, and re-cut. If it's still loose you have a serious issue. I've used .0025" a few times but the results can be iffey at best.

The next issue is not uncommon, but few understand it. The threads in the action were either single pointed (still have yet to see a Remington that wasn't done with a tap), or drilled and tapped. Just because you cut the threads via a lathe doesn't make them any good, contrary to popular belief. A headstock out of alignment will give you a tapered bore and a tapered thread (very common). Next issue is the two different machines cutting threads. Every machine has lead error, yet most will never see it unless the threads are very tight. As the thread turns the error starts to stack up.

Before doing anything, take a black felt marking pen and blacken the entire male thread. Now clean the female thread with brake cleaner. Thread the two together till they are very tight. Now remove them and look for bright metal on the male threads. That will show you where things are binding up. If it's all over, then you have bad threads (lead error, or just plain cut wrong). If it's the first two or three threads, then indeed you can run the tap thru the bore. I'd forget the idea of re-cutting the female threads on a lathe unless your a tool maker with a lot of practice. If it's not much of a bind, a tap might fix it.
gary

 

[Deleted member 46119]

What Gary said.

I purchased an action. Similar problem. Would not thread on a couple take off barrels.

I chased the threads with a bottoming tap. Problem solved.

I had a barrel I wanted to use that would not thread on multiple R700 actions. I chased that with a die.

The action is now a 277/26-Nosler that has been pushed far enough to know it's sound.

The barrel is a 28-Nosler. Same.

 

[shortgrass]

MSC Industrial part numbers for 1 1/16"- 16 UNS H4 bottom chamfer hand taps; Import 04861217 $117.24 , made in USA 74861212 $240.44 I'd figure out which was bad, the receiver threads or those on the barrel , before running a tap in. Most would have just sent the barrel back to where it came from if it didn't fit. After all, you did pay for one that "fit", didn't you?

 

[Trickymissfit]

MSC Industrial part numbers for 1 1/16"- 16 UNS H4 bottom chamfer hand taps; Import 04861217 $117.24 , made in USA 74861212 $240.44 I'd figure out which was bad, the receiver threads or those on the barrel , before running a tap in. Most would have just sent the barrel back to where it came from if it didn't fit. After all, you did pay for one that "fit", didn't you?

had to drill and tap

years back I was building a very large robotic cell (it is still the largest in the world). I had to drill and tap a hundred or so 1.06-16 thread holes. So I had the boss order in a dozen taps, and drills and reamers. I asked for machine taps (I didn't have an apprentice to hand tap all these holes<g>!) A box of stuff showed up, and I went to work on a big radial drill press (I was there for the better part of a week). Here comes the boss, and he's white as a sheet! He's got the bill in his hands for the drills and taps. Each one was a tick under $150!! The bill was a little over four grand. A week or two later I got a similar project for leveling screws on the same project. This time about two hundred of them, and they're 1.50-16 tpi threads. I had a similar tap on hand, and asked the folks if they could re-sharpen them. They could, so I only ordered in four taps, and the needed drills and reamers (good idea to ream the hole on big fine threads). The bill for those taps were $350 a piece! Looked around and came up with some reamers, so I needed drills only. Then I had to buy the leveling screws at about $25 a piece! Boss said I was going to get him fired when it's all said and done!
gary

 

[RyanTrials]

A few photos of old vs new barrel. You can see how the old bdl barrel has a few smaller OD threads on the end vs the new barrel.

I do a decent amount of iron threading at work and other mechanical things, im no dummy average joe shmoe weekend gun hobbyist, lol. I've also been looking into getting into gunsmithing, either schooling or apprenticeship type deal hopefully in the near future. No i'm not an experienced gunsmith yet, but I know what i'm looking at. Remington built these things on a production line, im pretty sure their quality control was a lot lower than Criterion (Krieger company) match grade hand lapped barrels.
Maybe remington wanted the last few threads to really bite into the action on their factory barrels to guarantee a mechanical lock type fit? Who really knows, unless you know someone that was personally there and knew the ins and outs of the tooling and operation. Can't just sit here assuming things on the internet saying Remington wouldn't have variation in their factory production line action threads.

The action threads are fine, its just towards the end where they taper that is making it a tight fit. You know the taper taps have at the first couple cutters?

Either way, ended up being able to slightly tighten the barrel up a tiny bit more and it headspaces perfectly! I would have taken some photos of the action but I just dropped it off to my gunsmith yesterday to get my recoil alignment pin recess notched in the action.

I am not going to mess with the threads yet. If the barrel doesn't perform as it should, i'll take it back to my smith and have him carefully put a tap through the threads to clean em up , face the action and bolt face. I'll lap the lugs myself. It should be interesting to see how it performs untrued vs trued. I am going to do a before and after test

 

[Hired Gun]

Using your headspace gauge, what is the difference in headspace between those two barrels measuring from the chamber end of the barrel to the base of the gauge using a good depth mic? No calipers for this one.

I'm betting the new barrel is more than a few thou deeper.

No barrel threads should ever be an interference fit. That could cause them to distort and gall. This is not a self locking joint like a pinion nut on a car. The less stress the better it will work. Nice evenly loaded threads is what you are after.

When fitting a barrel I draw up an action print and a tennon print including the calculated head space. On a hunting or tactical rifle I keep the end of the barrel .010" off of the front of the bolt lugs and the bolt nose .010" off of the bolt nose recess. The bolt nose relief should be about .010" bigger that your bolt nose for the same field clearance. If any of these touch accuracy can suffer.

Using a nut on a Remington could leave you a bit tight. One unburned grain of powder or one loose cleaning brush bristle will shut down your rifle if it's too tight.

 

[Punisher]

Thread mic.

Just measure the darn thing!

 

[RyanTrials]

okay okay... disregard my last post. I'll be having my gunsmith chase out and clean up the threads to even them out and see what he says about the fit... might as well just do it right the first time. He's going to true the face, clean threads, lap lugs, maybe bolt face cleanup (he thinks its overkill), as well as make the notch for the lug alignment pin!!

Got all the stuff to load for the new 7mm rem mag cartridge (new for me), already loaded up a load workup/break in rounds. This rifle used to be a 8mm rem mag, after hundreds of different loads and workups it seemed like I could not find a group better than 2", not to mention bullet selection sucked with 8mm. Stock will be here monday!!! Finally ill have a rifle I will really be proud of, im hoping. Exciting!!

 

[Edd]

Got all the stuff to load for the new 7mm rem mag cartridge (new for me), already loaded up a load workup/break in rounds. This rifle used to be a 8mm rem mag, .......

It defies all ethics known to mankind for someone to rebarrel an 8mm Rem Mag to anything other than a 7mm STW.

 

[RyanTrials]

Lmao. I know i know, I really was going to do it for a long time, bit decided ill take the reduced barrel wear and recoil vs added velocity. Im saving all my 8mm brass, and ill probably rebarrel to 7stw in the future with a 1-8 twist for those 195 bergs! :drool:

 

[Trickymissfit]

It defies all ethics known to mankind for someone to rebarrel an 8mm Rem Mag to anything other than a 7mm STW.

Ed; I gotta argue with you on this one. Take the 8mm mag case and neck it down to 30 caliber. You pretty much have a sharp shouldered .300 mag, or a .300 Jarrette. Just a great round. Of course you could neck it up to .338, and have a sharp shouldered .340 mag. (better yet a .358 Shooting Times Alaskan)

good day
gary