27 March 2022, 10:02
Canadian reloarderAction Work
I was wondering that if you have an action trued and lugs lapped is this a one shot deal or must this be redone with every barrel change. TKS
27 March 2022, 10:21
SlamFireIf you are not deforming the receiver seats or lug surfaces, nor bending the receiver ring, I see no need for addition receiver ring truing, lug lapping, or bolt face truing.
In fact, I am going to claim, you don't need to do any of those on an all original, all matching, all factory rifle. This is assuming you are not going to use the rifle in benchrest of F Class competition. I do not care for lug lapping as it removes case on the surface. I want as thick a wear layer as possible on both the receiver seats and lugs. As I have told gunsmiths if I have 80% lug engagement, don't fool with lug lapping.
I earned a Regional Gold and my Distinguished with this bolt
The contact, as judged by finish wear, is not 100%. Yet this rifle would consistently hold a little more than half the ten ring at all distances out to 600 yards with iron sights. If we were using optics, I am sure the groups would have been smaller. If you shoot a rifle enough, the lugs and receiver seats contact will increase.
Incidentally, removing material from the lugs, receiver seats, bolt face, all have negative consequences. The distance from the lugs to the cocking piece sear is shortened with seat truing and lug lapping. That has resulted in sear over rides as the cocking piece hits the sear too hard. Bolt face truing inevitably causes extractor tension issues in claw extractor actions.
I am also going to claim, nothing a home gunsmith has, will every be as accurate and repeatable as modern CNC machinery. If a guy, with an old Bridgeport lathe, claims he can better the machining tolerances of a modern CNC machining center, that person is mistaken. In my opinion, it is better not to muck with the dimensions on a modern action. If however, you are using some pre history relic, well maybe truing will line things up better. Might also create new, and unusual feed and extraction issues. Especially as bolt face truing increases the distance between extractor hook and rim.
27 March 2022, 10:28
Canadian reloarderThank you SlamFire for your response. What I have is a Trued Rem 700 SA with J C Custom barrel in 6mm BR. The barrel will someday have to be replaced and I was wondering if this work needed to be redone. Thank again
27 March 2022, 22:06
Russ Gouldthe action is trued to itself not the barrel .. the barrel is then fit to the action not the other way round.
29 March 2022, 01:29
SlamFirequote:
Originally posted by Russ Gould:
the action is trued to itself not the barrel .. the barrel is then fit to the action not the other way round.
That's right.
When you plan to have the rifle rebarreled, talk to your gunsmith about the reamer he uses, and the bullets you plan to use. And how he turns the barrel blank and reams the chamber to ensure that it is concentric. It is also worth talking about case head protrusion, and what limits the gunsmith allows on case head protrusion. I also do not want a minimum chamber. I like a chamber that is two thousands over the Go Gage. Minimum chambers are a resizing problem. You want the firing pin strike to be in the absolute middle of the primer, firing pin strike offset is bad. And you want the fired case to come out of the chamber with less than 0.001" runout. A concentric chamber will do that. If the case comes out resembling a banana, that is bad.
29 March 2022, 09:02
Canadian reloarderThanks again. As for the reamer I have my own Manson reamer that he done my 1'st barrel with. It has only cut 1 chamber to date.