R700 Lug Rub (outer)

[FoxSpotter]

I finally investigated contact wear marks of the right Lug of a rem700 b series that was supposed to be trued.

Most notable are three lines.

Can be seen on both the bolt and 3 threads in the action .

See pics.


I humbly assume...

A.
The action threads are point downwards...making the rear of the threads...bolt side, high.

B.
This may prevent the nose of the bolt from lowering when the rear of the bolt is pushed up by the trigger sear etc..

So.
Maybe this all works out for the best?

However... I suspect this might be costing me a bit of accuracy

A slight wearing can be felt on the lug...little grooves where it's contacting.

[FoxSpotter]

https://youtu.be/qObTSPjNG0s?si=0YXG8AFiAGYtWPcB

Awkward YouTube footage of ..The Rub

[Wapiti]

Trued?
I assume that the outside surface of one locking lug is contacting the inside of the action threads. Or am I looking at the pics wrong? Or why in the vid, you concentrated so much on those threads with your mirror?
Was another barrel fitted, or is this a "cleaned up" stock barrel?

[FoxSpotter]

Yes...out lug has marks...and the pic inside shows the threads of the action where the lugs rubs on them.
It's a custom barrel...and..the action was paid to be trued.

The barrel itself should not be an issue..unless perhaps the nose of the bolt is contacting the barrel...I hadn't considered this...and don't think it's an issue.

I just wonder how unconcentric the bolt raceway and or the action threads are for this to happen.

And wonder what the effect of this contact might be..

Thanks for your interest.

[deye243]

How does it shoot

[Wapiti]

OK mate, I'm NOT a gunsmith, but I've seen some TERRIBLE work from gunsmiths down on the coast...
My trade and my own stubborn demand that I do the best I can in my own expectation makes me quite keen in the eye though.
Chambering a rifle barrel and cutting the action thread is not a challenging task for a skilled machinist... scary first time though I'll admit.

OK, with that, I've dismantled and rebarrelled Rem 700's of my own, and used barrel blanks from MAB then TSE up here, and from the clearances inbuilt into that design, the ONLY way I can see that a locking lug on a Rem 700 bolt could ever touch the interior action threads is if the "trued" action threads, meaning supposedly cleaned up to the true centreline of the action, were done offset to the bolt raceway centreline.
\
Now that is only going to happen from a bodgy machinist job set-up. Or the apprentice. If there is such a thing in Australia anymore.

If some goose was to thread a new barrel offset, forcing the nose of the bolt sideways into the side of the action, that may also be the case but when closing the bolt it would really "feel" this happening.
The nose of the bolt would then also show wear on it, but I can't see that being the issue myself.

[FoxSpotter]

I don't really want to ..but...I think I'd best contact the company....they are busy and often slow to respond...and I don't like to seem troublesome....however..i did pay for truing..and the threads seem to be well off centre..thus the rub...
I always wondered how I'd know if the action was actually trued...how could one possibly tell....

[Wapiti]

I actually think that, if my explanation is what's happened, that action is now buggered.
But hey, I can't see the rifle so I may be wrong for sure.
As I said, if the barrel could be removed, the action stripped and both set up, clocked completely on centreline, the real culprit will be obvious by running dial indicators over both individually and the action thread pitch be accurately measured and also checked for on-centre.

I think the contact with the threads needs to be addressed though, it won't help with a nice, straight recoil path and therefore the most consistency in the rifle's performance.

If the rifle shoots OK, and it will be completely safe anyway, the only way to stop the contact from the lug against the action threads would be to disassemble the bolt, put it in a 4-jaw and skim a few thou off the outside of the lugs to stop the contact. And re-blue.
This will not in any way, take material off that makes the lock-up any weaker.

[FoxSpotter]

I've contacted the company that apparently tried the action.
.I suspect I'll be selectively ignored...as it's a hair ball...on one hand...bad work or no work done...on the other they should fix it.

The rifle shoots ok...but..should be better...I expected more....but.its adequate. A problem the rifle has had is shift of poi...which might be me..with a poor zero adjustment.re wind...
It's been bedded..fat redoild lug.mfree float...should be no poi shift.(And maybe there wasn't..just me?

[FoxSpotter]

...and ...skim a bit off...problem solved... maybe..but...not the source of the problem.

I noticed on another r700 both a slight wear marl onnoutosee of lug...I dared not further investigate

[FoxSpotter]

https://youtu.be/eEDOPSJzzuQ?si=n_UeOLxoIzRZfHnd


Second video of the rubs...including bolt nose rub at bottom..on bottom half

[Wapiti]

...and ...skim a bit off...problem solved... maybe..but...not the source of the problem.

I noticed on another r700 both a slight wear marl onnoutosee of lug...I dared not further investigate

Mate, I'm a R700 fan, and have had many of these rifles, and still do. As have mates of mine who'll pay that little bit extra for a great working rifle.
I've never seen locking lugs or a bolt nose that misaligned to rub on the inside of the action, on anything.
You gotta PM me who's done that work.

[straightshooter]

Despite the poor photography it seems fairly apparent that the bore in the barrel is offset in relation to the central axis of the barrel.
I come to that conclusion because I doubt whether a receiver with that amount of offset would have left the factory
From the rub marks on the bolt nose one can see that the chamber counterbore is forcing the bolt into alignment far enough to cause the rub marks on the lug.
If the rifle shoots acceptably then stop whingeing.
If it doesn't then a new barrel is required, fitted and chambered by somebody who is a bit more diligent than whoever did your current barrel.
How about giving the receiver internals a good clean. Looks pretty grubby to me.