New barrel question

H

hepburn45110

Member
I am in the process of collecting parts to assemble a new bench rifle. I have read several things about lapping a taper in the barrel. Seems .0001-.00025 taper was the accepted amount of taper needed. If you have a new barrel and the manufacture states that is has a taper lapped into the bore would you mess with it or just shoot it?
 
New barrel

hepburn45110 said:
I am in the process of collecting parts to assemble a new bench rifle. I have read several things about lapping a taper in the barrel. Seems .0001-.00025 taper was the accepted amount of taper needed. If you have a new barrel and the manufacture states that is has a taper lapped into the bore would you mess with it or just shoot it?
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I'd definitely shoot it before messing with it!

Bill Schertz
 
Zero taper, and anything between that and .0001 is also fine. What you can't have is an taper in reverse, thats all. I have an old 75 Winchester from the early 50's with no taper whatsover....slug pushes even from end to end; it is a superb shooter. Only mentioning this because many a straight bored good shooting rifles have been ruined by someone trying to lapp in an unneeded taper.
 
Greasy said:
Zero taper, and anything between that and .0001 is also fine. What you can't have is an taper in reverse, thats all. I have an old 75 Winchester from the early 50's with no taper whatsover....slug pushes even from end to end; it is a superb shooter. Only mentioning this because many a straight bored good shooting rifles have been ruined by someone trying to lapp in an unneeded taper.
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Or if you have any tight spots no matter how small then lapping is necessary.I believe that most of the top barrel makers in BR lap tapers into their bores nowadays, there are some exceptions.A few of the top gunsmiths lap their barrels after chambering them but they are trying to get the raw edges off the chamber after cutting the chamber not trying to induce a taper.
MC
 
A friend has done some experimenting with lapping both RF and CF barrels. He has been able to improve some barrels, but it has been a long trip that no one should start unless he is a very talented and bright craftsman, and understands that his mistakes will be the cost of learning. Currently, most of what he does is cast laps to evaluate barrels, new ones before he does any work on them, and customers' to see if he can detect a source of a problem. Generally, I would not recommend that anyone try this on a barrel that is important to anyone until you are sure that you have acquired the necessary skills.

As to taper, perhaps it is needed for lead bullets, but if a barrel is truly parallel, and properly dimensioned, it is not needed for jacked bullets, and may in fact lead to break in problems due to jacked fouling in the choked area, if the choke is much over .0001. Personally, I would not want .0002 for that reason.
 
Lapping:

Straightening out a barrel with a few flaws is a relatively simple process. First and foremost, one must develop a "Feel" for how a proper barrel should feel, when stroking a snug fitting clean patch through it. This feel tells all one needs to know. Lapping the bad spots out with patches and compound is sufficient. It is my view that many, many barrels get relegated to the stack of loosers too early by two things, 1. folks not knowing how to clean their barrels properly and 2. folks not knowing how they should feel when they are right. Those who possess "magic" know these things and are able to make rifles shoot. I'm thinking there are many, many barrels in the pile that are hummers if someone who understands them works the "magic".

Pete

P.S. Without a borescope, we all dance in the dark.
 
Not ong ago,

BC posted an explanation of lapping with patch & compound not long ago. It was no BS, that post. His success, I believe, is the magic of feel and then lapping the spots out. Most of his rifles shoot and there is probably a reason why they cost as much as they do, perhaps the extry work to get them to feel right. It is not at all unusual to find rough spots in barrels that attract lead; don't know why but I suspect the amalgam of the metal is not consistent. When one sees a gray patch, they have lead and the accuracy will not be restored until patches are white. I have found lead all over the place in my barrels. I'm on my 4th year with a couple of my barrels that are still shooting as well as I can read the wind. Gotta know how to clean them is all.

Pete
 
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