Originally Posted by Clay Target Guy
Please don't think I am arrgueing (just trying to understand), but how can the bolt be on the same CL as the action/barrel when it has .005-.006 clearance?
Would the CL of the bolt not be out by .003 (approx) but if done correctly is should be parallel and square?
Thank you for your time to teach me
You are not being argumentative, just asking questions.
If everything is machined true to the centerline of the bore and the head space is .000 to .001 (I like slight pressure on the case head) -.0005 to .000 so it squares everything up before firing, the center line of the bolt is very very close unless the bolt face is to large allowing the bolt off center by .001
or .002 thousandths. Even if it does the bolt face will be square to the bore and the cartridge will still be on the same center line as the bore and will not move upon firing.(Common with poor fitting parts).And is Very important for the best accuracy.
So the fact that the bolt could be several thousandths below the center line of the bore, there is no way of measuring it and no need to if everything is fit as near perfect as possible. To be a perfect fit in every way you couldn't have any clearance between the bolt and the receiver and it would not be
functional. The trick is to get everything as close to perfect as possible but still be functional.
A bolt that has .005 + clearance should be replaced with a over sized bolt and the receiver reamed to fit within a couple of thousandths.
If everything is done this way the bolt will have a tendency to find it's way to the same spot, Square and centered every time.
So I have to agree with you that It is not perfect but done right as near as possible.
A "proper" Blue print will help accuracy, consistency, wear,and improve brass life so in my opinion it is not only important but a must if you are looking for the ultimate accuracy.
Hope this helps
J E CUSTOM