bore curvature, barrel indexing?

404tbang

Member
Howdy!
I saw a thread regarding barrel indexing last week. I think Jefferson started it, with more to come. I see that Gene Beggs is going to post info when things get back to normal following a funeral. (Deeply sorry for your loss Gene.)

This question has been bugging me.

Apparently it is very difficult to bore a straight hole. If the barrel is straight, the hole may not be. If the bore is straight, the barrel may not be.

Is it not possible to straighten the barrel to the bore, then remove any external metal that prevents the barrel from being straight?

Would the removal of that metal affect the inner dimensions of the bore to the point that the bore is no longer straight?

Is the point of indexing a barrel to straighten the bore, and position the barrel so that any external curvature of the barrel would be in a vertical plane to make tuning easier?

I read somewhere in here that Bill Calfee once built a rifle using a Remington 37 barrel that shot best with the barrel mounted upside down to the reciever. I don't know what further testing he did regarding indexing.

I can't find Jefferson's thread, or I would have added this to it. I don't want to step into territory that Gene will cover, but I don't know if my questions would fit in to either thread.

Jefferson and Gene, if this thread will interfere with what you have planned, I will delete it.

This has been bugging me, and I am trying to learn.

Thanks!
Greg
 
barrel indexing

Go to M. Werks web site. They do barrel indexing & have some pretty good information on indexing. I was reading somewhere else about indexing & they had sample targets of the improvements indexing makes but ill have to locate where that was But it definately makes a difference.
 
It's one thing to straighten a barrel that is not straight, but how do you straighten the bore? Most bores that wander do so as a helix and not a curve.
Butch
 
barrel straightening

Howdy!
Big G, thanks for the info, I will check it out!

Butch, I made that statement based on something that I was told about Eric Johnson. If I understood properly, the guy told me that Eric would straighten the barrel after each cut. I will call the guy back to verify, but he definitely said there was a bunch of straightening after the cuts. I have seen pictures of guys peering thru barrels fixed in straightening jacks. Seems they would have to straighten the barrel based on what they saw in the bore.

I have a copy of a recommendation from one of Eric Johnson's former employers that stated he was particularly good at straightening barrels.

I can't imagine being good enough to see enough looking down the bore to tell if something was a bit out. Way off, yeah, but a little? 'twould take boatloads of exerience I don't have.

Thanks for the input guys!
Greg
 
404 type in Harvey's Hot Rod Anschutz BR-50 & it will show you some targets indexed by Mike Ross. Good article on indexing also. The targets are way down at the bottom of the page.
 
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