So I stretched the number of loadings (and perhaps their intensity) a bit too far. Can or should this be corrected when a new barrel is installed on this Rem 700?

From an accuracy standpoint there's more disturbing things going on with that bolt than the appearance of the bolt face.

If it hasn't already been corrected once or twice before, the answer generally is "Yes" if it isn't TOO deep. It is a matter of turning the bolt face flat again in a mill or a lathe.

Depends on the machinist and his tools as to which he may prefer.

Normally that kind of damage is from primer leaks. I'd back off a bit on my loads, or get a bigger gun/cartridge if I really needed more power.


BTW, it looks a bit like the front of one of your lugs is bearing against the barrel stub...and the other isn't. Vas ist los?

quote:

Posted 11 July 2009 06:25 Hide Post
From an accuracy standpoint there's more disturbing things going on with that bolt than the appearance of the bolt

Right on WestPac.

The rear of the barrel is rubbing against the left bolt lug.

I see said the blind man! And to think this was perhaps the most accurate barrel I have ever owned! Cartridge was a 6.5/284 and the rifle shot in the high 1's low 2's with consistency.

I do however see the issue raised. Perhaps that was only on an empty chamber?

quote:

"...the rifle shot in the high 1's low 2's with consistency"

Would that be in inches or thousandths?

If the rifle is shooting that good why worry about the bolt face?

I find it difficult to determine if that lug is actually "rubbing on the barrel" without having the rifle in hand to check it out. That rub mark may have come from another source. Possibly with another barrel. Hard to tell from a photo.

quote:

Originally posted by Westpac:

quote:

"...the rifle shot in the high 1's low 2's with consistency"

Would that be in inches or thousandths?

If the rifle is shooting that good why worry about the bolt face?

Westpac....are you asking about the ranges at which the barrel shot those groups CONSISTENTLY? Yeh, that's what I thought.

quote:

Originally posted by DocEd:
I find it difficult to determine if that lug is actually "rubbing on the barrel" without having the rifle in hand to check it out. That rub mark may have come from another source. Possibly with another barrel. Hard to tell from a photo.

No, the only barrel to have ever been on that action was the aforementioned 6.5/284.

Ah, yes it was in thousands... funny

308Sako, in that case, I would put some layout fluid or, magic marker, on the front of those lugs and place the bolt in the rifle. Opening and closing the bolt a few times should let you know if there's contact.

DocEd, Thank you for the suggestion, but the action is being shipped off to a full time GS for rebarreling. I will suggest he look at this when he examines the action.

Thank you for your kind reply.

quote:

Originally posted by 308Sako:
DocEd, Thank you for the suggestion, but the action is being shipped off to a full time GS for rebarreling. I will suggest he look at this when he examines the action.

Thank you for your kind reply.

You shouldn't have to suggest anything to the gunsmith. He should be alert enough to catch everything.

quote:

Originally posted by Westpac:

quote:

Originally posted by 308Sako:
DocEd, Thank you for the suggestion, but the action is being shipped off to a full time GS for rebarreling. I will suggest he look at this when he examines the action.

Thank you for your kind reply.

You shouldn't have to suggest anything to the gunsmith. He should be alert enough to catch everything.

Yes that is true, but I rather talk about my action than Mikey Jackson's recent demise.

quote:

Yes that is true, but I rather talk about my action than Mikey Jackson's recent demise.

Why not talk to him about both? I'm sure it would mean so much to him.

quote:

Originally posted by D Humbarger:
The rear of the barrel is rubbing against the left bolt lug.

I don't see that as a problem. I set up my remingtons (and remington clones) this way. When you close the bolt on an empty chamber and release the tension on the firing pin spring, there should be a little slop in the bolt fore and aft. If you slide the bolt back while in battery, the lugs should contact the receiver (obviously) but when you slide the bolt forward and there is no cartridge to stop it, then what should it hit? If the bolt handle hits the front of the notch in the receiver then you get a visible wear mark there. The only other options are for the bolt snout or the front of the lugs to contact the barrel. I prefer the lugs because they offer a wider contact surface that has open spaces to allow contamination to get out of the way (so no binding).

To the original question, that should be no big deal to cut back that bolt face a bit to clean it up.

And if the front of only one of the lugs hits the rear of the barrel, as in this instance, what does that suggest to you that you might want to check, if anything?

Why does that matter? I've never heard of anyone truing the front of the lugs. If that left one sticks further forward, that may be a good thing because it will get all the wear, and the right lug (the more visible one) will keep its blue. I've noticed that it's possible to spend a lot of time messing with a remington action trying to get it 'right,' so I still wouldn't bother truing the front of the lugs. In the picture above, the machine marks don't even look consistent from one side to the other.

quote:

Originally posted by jpl:
I've never heard of anyone truing the front of the lugs.

Well, you have now.



Here's another angle.





Infact, the entire bolt head is trued. I true them all. When a customer is shelling out good money to have a tack driver built, you don't want one lug to outweigh the other.

I don't know about you JPL,but having the front of one lug bearing and the other not would make me want to check the trueness of the barrel and receiver threads, and maybe also check whether the action is slightly bent. I mean, the faces of the lugs might be spot-on the same size and true. If so, why IS the one lug making contact and the other not?

Then, using your own logic, I'd want to check to make sure there IS some play between the bolt and the barrel when compression is released. There may NOT be, eh?

Not trying to criticize either you or the fellow who put together the gun being discussed. Just mentioning things that would start going through my mind if I was working on that rifle.

I guess maybe I am just anal that way. When a rifle leaves my shop, I want to know for sure I haven't missed something I should have caught and might have been able to fix for the customer's best satisfaction. I call it "pride of workmanship" but it probably is just considered "anal" these days.

Best wishes,

AC

Generally speaking, whether or not the front of the lugs are true to anything is meaningless. It only makes measuring easier. If the lug was contacting at any time other than when the bolt bounced forward when dry fired, such contact would be very noticable. In fact, galling would be a near certainty.
When a Remington is dry fired, I would expect the left (top) lug to contact and not the right (bottom) lug. Why? The bolt fits in the receiver with a significant amount of clearance (probably on the order of .008" or so). When dry fired, the cocking piece overrides the sear but the sear still holds the bolt up against the top of the receiver bridge when there is no other influencing forces to counteract the sear spring. So, the top lug hits the breech end of the barrel and the bottom lug does not. Remove the trigger and let the bolt bang against the barrel a few times and both lugs will probably be marked.
There is one aspect of machining the front of the lugs which is well illustrated by Westpac's pictures; it makes them pretty!
When I was shown how to barrel Remingtons ( by a fellow AC might have known, Art Bourne) I was told to take a cut on the front of the lugs, the front of the bolt nose, and the circumference of the bolt nose. In truth, the bolt face was the only important surface. The others were just window dressing.
In the case of a bolt face which is gas cut like the one shown, I will face it back up to .005 but don't like to go much further as it may cause primary extraction problems. Regards, Bill

quote:

Originally posted by Bill Leeper:

When I was shown how to barrel Remingtons ( by a fellow AC might have known, Art Bourne)....

Gosh yes! Bill. I remember one time Art was over here (in Calgary) with Bob Hobbs, shooting in the APR annual championship tournament at Sarcee Ranges. Don't recall what action he was shooting, but think it may have been a Savage. Anyway, was chambered in 7 m/m RM, with a left hand twist. He must not have cinched it up very tightly 'cause at the 1,000 yard line it had shot itself loose and turned out about three threads... You should've seen those cartridge cases...!


I was told to take a cut on the front of the lugs, the front of the bolt nose, and the circumference of the bolt nose. In truth, the bolt face was the only important surface. The others were just window dressing.

I see where you are coming from, but I still like to check the WHOLE action out if I see anything which may indicate an imbalance created by a previous effort of a shade-tree mechanic. That, of course, doesn't usually turn out to be the case, but it is amazing what you find some times.


In the case of a bolt face which is gas cut like the one shown, I will face it back up to .005 but don't like to go much further as it may cause primary extraction problems.

And I think that is an excellent guideline, which is why I first said "Yes, if it hasn't been done before..."

Regards, Bill

Regards back at ya, Bill. May see you in a few months. Der frau is about to retire (September) and we are thinking of moving back to either Alberta or the Pinticton area of B.C. I am having a bit of trouble here getting comfortable with the Obamaites' vision of making us wealthy by borrowing two trillion dollars we don't have, in two years....and in addition possibly enlarging the Afgan war.

Thanks for the replies and pictures! That looks like nice work and the information is good too. Is that a tubb extractor?