Blueprinting V/S Square & Lap REM 700 Action

D_Bell

D_Bell

Active member
I am about to rebarrel a REM 700 action, I will be shooting long range varmints with it.

Is it worth blueprinting the action, or should I have the action face squared and the lugs lapped?
 
For me, blueprinting a Rem 700 for a semi custom build is the same as my thoughts on bedding a stock, whether it's worth it or not, I always have it done and just like a proper bedding job, done right, a trued action will only help make it shoot better.

It doesn't cost that much so IMO it's worth it.
 
A couple of things to for you to consider. First, a question for you. What is the goal of lapping the lugs in a bolt action? Of course the answer is "so that both lugs have full or near full contact with the receivers lug abutments." That having been said, what happens to the bolt when it has somewhere in the .008 to .012 clearance in the receiver and the angled trigger sear pushes up on the bolt from the main springs pressure? The answer is that it unseats the top lug off it's seat. Here's the take home message... If you lap the lugs to full contact without the trigger in the receiver the bolt will lift up, unseat the top lug and all your lapping did was to reduce primary extraction by setting the bolt back a few thousandths. You still don't have good contact. If you lap the lugs with the trigger in the receiver you can achieve good lug contact but the bolt now is setting in the receiver crooked with it's back ent up against the rear bridge and THE BOLT FACE IS GUARANTEED NOT TO BE SQUARE TO THE CENTERLINE OF THE RECIEVER. In that situation your cases would have their case heads angled after every shot and you would essentially have variable headspace every shot depending on how the case was oriented in the chamber relative to the case head. That's not what you want.

The only way to do this correctly is to sleeve the bolt body (or at least the rear end of the bolt body) and then do the machine work to square everything else up to the centerline of the action. After that is done you can lap the lugs with the trigger in or out and you will end up with the same result.
 
^^^^ a la Borden bumps. Have customs with that feature built in. Have 700's with sleeved bolts, done in a couple different ways by a couple different 'smiths, but I like the way Greg Tannel does it.

- DAA
 
Bangpop,
I thought after the cartridge fired the 60,000 PSI or so of pressure would be enough to push the bolt back a couple thousands to make full lug contact, regardless of the trigger sear?
 
I dunno if that's true or not. Knowing for sure what happens at 60k psi is way above my pay grade. A couple of things that I can say for sure are that the rifles that I have sleeved the bolt on tend to shoot better than those without sleeves. By that I mean that they are more consistent and shoot very few, if any, flyers that can't be explained by wind or mirage. Another thing that I would point out is that I do have a couple of actions that I have elected not to sleeve the bolt on for personal reasons. I have two OLD 40-x actions that are so slick and smooth, and are chambered in cartridges that I don't put extreme demands on for accuracy/precision, that I didn't see the point in doing the sleeves. I trued both of those actions up but didn't sleeve the bolt and after the machining was done I had a friend blue them to protect the raw surfaces. The top lug on both of those rifles still has virtually all of the blueing left and one of those has about 4500 rounds through it since blueing and the other is getting close to 6000. It would seem to me if there was much in the way of touching that that blueing would have been gone a long time ago.

A good shooting rifle can certainly be had without going to the trouble of sleeving the bolt. There's no question about that. I see enough benefit to the procedure that I do it as a part of the truing process.

This stuff is interesting for sure.
 
You're right, there is a lot to it. There's even more to it than the discussion above. The piloted tap method is popular with many gunsmiths because it's faster and easier that the single point tool and lathe method. The one thing to remember about a tap is that it will follow an existing hole for the most part in spite of the bushings trying to guide it. The only way to get the action threads EXACTLY on center is with a lathe.
 

I have a 700 Remington and 10 Savage that I have had blue printed and timed.
Then, I have Ruger M77 II in 220 swift that shoots just as good.
It is totally stock, I have never had it apart.
It is that pretty gray finish, rings and a Leopold matching gray 4.5X14 scope.
If I can see Mr Groundhog I can hit him.
You can see it nice rifle. I have never seen one like.
I was lucky to find the scope. $$$

0r0BVGP.jpg
 
Willy, I passed up the exact same rifle at the gun show this week-end. No more used 220 Swifts for me unless I know the guy who owned it. Nice rifle though. My smith also has one too.
 
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