Truing an action.

I recently had a 700 receiver in with 0.0007" TIR at the face and lugs and about 0.002 on the threads. Probably wasn't worth working on but after all the setup and dialing in time, the cutting just takes a few min.
 
When you use the jig put the screws down in the back by the head stock first and don't put the front screws down yet. Put the mandrel in the tailstock and just dial in the rear of the action. When the rear is running pretty straight then run the front screws down and remove the tailstock. Your action will be 95 percent running true already. Then it only takes a few back and forths to get it done. That's my tip of the day for ya. Try it you will be amazed.
Shep
 
Jrock I'm in the same boat as mram. If it was that close I would just let the face of the receiver straighten out the barrel. That's why the barrel tennon has to have some play in it.
Shep
 
So you would still cut the face of the receiver? that is what I take "...let the face of the receiver straighten out the barrel"

I did a savage truing of the threads once so I could keep prefits working but I will never do that again. I would rather just face the lugs and face of the receiver and have sloppy threads.
 
I tell my customers not to do a blue print on hunting rifles unless there is a big issue like only one lug touching. And if that's the problem and I measure the lug seats on the action and they are equal then I will only the the back of the lugs on the bolt. I only charge 200 for a full blue print but I tell my guys buy a good trigger instead. I still guarantee 1/2 moa so what's to lose.
Shep
 
When you use the jig put the screws down in the back by the head stock first and don't put the front screws down yet. Put the mandrel in the tailstock and just dial in the rear of the action. When the rear is running pretty straight then run the front screws down and remove the tailstock. Your action will be 95 percent running true already. Then it only takes a few back and forths to get it done. That's my tip of the day for ya. Try it you will be amazed.
Shep
I have been doing the front screws first then the rear screws, so the exact opposite. I'll give her a try your way and let you know. Thanks Shep.
 
Just make sure the front screws are not in the way. The put the indicator on the mandrel in front of receiver and you can easily dial in the back. The front is already going to be close because the center on the mandrel. Save you a bunch of time.
Shep
 
Truing is one of those things that you either commit to doing it right or you just don't do it. If you fight dialing in that indicates either a weekness in your set up or just need more practice.
The only times I've fought it was when I was using home made tooling or **** poor PTG tooling and things just wouldn't settle in. Dial intakes me a few minutes tops but the way my jig is I loosen two pairs of marked screws one turn and the sleeve is out with the action then back in with the next one tighten one turn and do a final dial in and we're on to cutting.
 
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Truing is one of those things that you either commit to doing it right or you just don't do it. If you fight dialing in that indicates either a weekness in your set up or just need more practice.
The only times I've fought it was when I was using home made tooling or **** poor PTG tooling and things just wouldn't settle in. Dial intakes me a few minutes tops but the way my jig is I loosen two pairs of marked screws one turn and the sleeve is out with the action then back in with the next one tighten one turn and do a final dial in and we're on to cutting.
Got a 4 jaw dedicated to chambering and it's the same way. Half turn of each gets it just about there. I'm sure practice helps since I've only done 2 actions on this new jig.
 
I get my barrels straight quick too. I put the chamber end in the tailstock and dial in the muzzle then I just tighten the 4 jaw around the already centered barrel. Bam it's within a few thou just that quick. All these little things add up to big time savings. I told a friend of mine how I cut Chambers so fast and he was blown away. He said why didn't I tell him that 20 yrs ago. I didn't know him 20 yrs ago. Sorry Viper about all the lost time.
Shep
 
Bob is a good guy. A little crazy. Well ok alot crazy. But eager to share his success with anyone. I've never seen someone dominate fclass the way he did.
Shep
 
An action's lugs need to be a hell of a lot better than .001" tir if you want lug contact unless you have a very loose fitting bolt. Trig it out. We are talking a couple tenths here. If your not going to do it to that level, there is no point in doing it. If your not addressing the ignition system as well, truing the action may not be the best money spent. The lug seats are far more important than the action face.
 
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