I've read through past posts on this, an one thing pops out that I need confirmation of.

Is it possible to headspace a barrel to a 700 action by varying the thickness of the recoil lug?

eg I have a 22-250 Rem properly headspaced etc etc. I source a brand new 308 Sendero take-off barrel. It fits the action no problem, but the bolt won't close on a "go" gauge ie the headspace is too short. Can I correct the headspace by making up a thicker recoil lug?

Logic tells me you unscrew the barrel slightly, insert the go gauge into the chamber and screw the barrel in till it stops on the "go" gauge. The distance between the barrel shoulder and the receiver face is the thickness of your new recoil lug. Obviously I'd have to keep the special recoil lug with the barrel.

Am I missing anything in my reasoning?

Other than your also increasing the unsupported gap between the bolt head and the chamber?

Wouldn't it be easier to simply run a reamer in a few thou, and not have to worry about mixing up the lugs?

I knew it wouldn't be that simple!

Thanks!

Pete you need to determine how much the headspace is short. a easy way to do this is to screw the 308 barrel onto the receiver but leave it loose. Chamber a round & close the bolt. Then gently screw the barrel till you FEEL tension on the bolt when you lift it. Useing a feeler gauge between the barrel shoulder & receiver lug or the lug & the receiver face you can easily determine the amount of extra depth you need.

Pete,

I know this sounds silly, but have you made sure the bolt will close without the headspace gauge in the chamber? There is a chance the bolt nose could be contacting the barrel. Also, check the new barrel with a loaded round to be sure the casehead is supported to the extractor groove. If the case is fully supported, there should be no issue with the thicker recoil lug or even making a thin spacer.

quote:

Originally posted by Pete Millan:
.

Is it possible to headspace a barrel to a 700 action by varying the thickness of the recoil lug?

eg

Pete:

Yes you can, I have several lugs that I use.

Terry

quote:

Originally posted:
Pete,

there should be no issue with the thicker recoil lug or even making a thin spacer.

I have a .404 Barnes Supreme (essentially a .416 Remington Mag, but using .411" diameter bullets, and 30 or 40 years older). It was barreled by the RCMP national armoury in Regina, using a very, very thin spacer between the recoil lug and the barrel shoulder to achieve the proper headspace. It has worked fine that way for the last 37 years.

just to be safe...don't rely on cases for headspace.. A "go" gage means safe for even the longest facory case

DITTO what Duane says...brass can compress or possibly change throught the same process as case sizing...a steel gage in/on a steel chamber and bolt will NOT unless you get ham fisted or loose your mind...

AND...I was taught to make it simple...and to modify the LEAST expensive and easiest to mess with part...no matter WHERE the part comes from...I would make sure the bolt nose has clearance...you can use lipstick or grease pencil or shims the check that...THEN modify the sizing die or shell holder if I needed to shorten ANYTHING.

Have you tried a factory round to see just how much "camming" is required to close the bolt...or rent a reamer for <50 bucks to lengthen the chamber?

Doug gives you a quick and easy way to find out just how much you need to cut...I use basically the same method.

I guarantee there are much simpler, easier and cheaper ways to solve your problem...ANYTHING rather than messing with bolt heads...

Luck

Thanks guys for the input, I've got a "go" gauge for both 22-250 and 308.

This whole scenario has not happened yet - the 22-250 is still at the smith getting a Shilen barrel installed. Some time in the future I'll find me a new take-off 308 or 243 barrel and stick it on, using the suggestions above.

Thanks again!!

quote:

Is it possible to headspace a barrel to a 700 action by varying the thickness of the recoil lug?

Yes, this should work fine. You may want to consider things like: the bedding arrangement, maybe pinning the recoil lugs to keep them clocked, will each barrel have a different contour, how will you be changing the barrel, will you want to change it at the range, how will you keep track of scope zeros for each barrel, etc. Good luck!

Hi jpl,

I've asked the 'smith to pin the lug. I've got the barrel vise and wrenches, more than likely I will change out at home. All good points, I am going to have a lot of good housekeeping to do.

Cheers

pete