Gunsmithing lug truing question

[steelcomp]

I'm working on a Sako M995 action, and was wondering about doing some basic reworking, like truing the lugs. I used black magic marker on the bolt lug faces, then pushed the bolt in and while pulling back on it with the bolt handle, wiggled it as much as it will move...enough to show that only one of the lugs is making contact...which I don't find surprising. Since I have the barrel off, I can also look down into the receiver and see where only one lug shows any wear.
My question is, is it enough to just remove enough material from the one bolt lug until all three make contact? Without any real means of checking, I'm not sure weather it's the receiver or the bolt that's off...maybe a little of both, but in the end, if all three are making contact, is that not an improvement?
TIA

 

[FALout]

Re: lug truing question

You could be pulling the bolt at a slight angle (without even knowing it)giving you a false reading. I'm sure someone can post a pic, you can make(or buy) a device that threads in like a barrel, this device will be spring loaded to put pressure on the bolt in a more straight line fashion, hence, giving you a better idea of lug contact. You would also use this device with some lapping compound on the lugs to get better, even contact.

 

[steelcomp]

Re: lug truing question

The bolt on this rifle measures .745", +/- .0002, and the bore in the action allows a .749" dia. ground rod to pass throug, but not a .751, so I can safely assume there's only ~.005 clearance, or .0025 in either direction from center. Not sure what that angle is over 5.25", but it's not much. The way I see it, if only one lug is bearing, then putting pressure on the face of the bolt is going to force the bolt to one side of the action anyway, pivoting on the one high lug. (Sako action has three lugs). When I'm applying pressure with the handle, I can actually control which direction the bolt moves, and keep the pressure on the side of the bolt with the high lug.
Does that make sense to anyone?