I have a Sako with a 3 locking lug action I would like to lap the lugs, how do you lap lugs and what lapping compound do you use? Thanks for any help!

Jeffe should give you his procedure cause he is the expert but I will caution that this is a perfect way to lap you chamber OUT of headspace spec.

First thing you want to do is check the headspace to make sure you can safely remove material.

To do it right, you need to apply steady, even pressure against the face of the bolt to keep the lugs in contact during the procedure. Removing the barrel facilitates this a lot better than trying to do this with the barrel in place. I would completely strip the receiver so as to avoid getting any abbrasive into critical parts.

Brownells sells a pretty slick kit for doing this job:

http://www.brownells.com/aspx/NS/store/productdetail.aspx?p=414&s=

The procedure itself is simple. Apply the abbrasive to the receiver lugs, insert the stripped bolt body into the action, apply steady pressure to the bolt face while working the bolt handle up and down.

You may want to get a coffee can full of Kerosene and brush to wash the abbrasives from the bolt and receiver at the end of each cycle.

I will usually cycle the bolt handle 50 times, then wash the parts really well, check the headspace and repeat as necessary until I see uniform contact. Then I will switch to a finer grade (800gr) abbrasive and give it one more set. After that I will detail clean the bolt and receiver, re-check the headspace, oil and assemble the gun.

If your lapping the lugs prior to re-barreling, Brownells has a tool that screws into the receiver and has a spring loaded plunger that bares against the bolt face while you lock and unlock the bolt. As Peleg says, I wouldn't do it on a rifle with the barrel already fitted. You could very definately develop a case of excessive headspace.

quote:

Originally posted by Masterifleman:
As Peleg says, I wouldn't do it on a rifle with the barrel already fitted. You could very definately develop a case of excessive headspace.

Like Malm say's, that's why you measure the headspace first. To determine whether it will be safe to proceed or not.