PDA

View Full Version : Benchrest gunsmiths ??



bdotson
11-16-2010, 09:28 PM
Ok I have been visiting with two who will remain un named benchrest gunsmiths. I have guns from both of them. One is as I would expect very precise indicates the bore in to within .0001. The other say most all barrels are as he puts it crooked as a chicken wing, says the reason people use a floating reamer is so the crooked bore dont break there reamer. He tells me he simply puts the barrel in his good 3 jaw chuck and runs the reamer in. Also says he dont use no coolant flush system never has, just dip your reamer in cutting fluid and let er go. As I said earler I have guns from both smiths and as you might have guessed it the latter out shoots the first. Why? Question are new barrels crooked if so how much? If so why do we try and set them up so close? Does it matter ? What matters and why?

Butch Lambert
11-16-2010, 10:42 PM
Barrels are not crooked. The bores may run around in the barrel. I would suspect that the guy was pulling your leg or he got a great barrel to start with.
Butch

bdotson
11-17-2010, 06:58 AM
Barrels are not crooked. The bores may run around in the barrel. I would suspect that the guy was pulling your leg or he gpt a great barrell to start with.
Butch

I guess I should have made it clear in the earler post, when I refered to barrel I was speaking of the bore being crooked due to the deep hole drill walking off as the barrel was made. Not the O.D. I dont think the guy was pulling my leg, his point was if the ID is not true why try and line up on it. His gun shoots well. So how important is it to put in the time to indicate in to .0001. Can any one gunsmith consistantly make his guns shoot better than others? Or Is it just luck of the draw when you buy the barrel or is it more to do with the guy fitting the barrel?

SGJennings
11-17-2010, 08:52 AM
OK, I'm not a benchrest gunsmith or a gunsmith of any stripe. But, it seems obvious to me that while the entire bore might wander around, the chamber end is *locally* much straighter and it makes sense to cut the chamber concentric to it.

In the context of other industries, I have read articles on deep drilling with lasers. I wonder if, given the almost cottage industry nature of the benchrest barrel business, that technique will ever penetrate.

Butch Lambert
11-17-2010, 09:32 AM
Mr. Dotson,
It is a combination of both. You may have been lucky once or probably it would have shot much better if more care had been taken during chambering. BR gunsmiths have ways in their setup to minimize the problems.
Butch

Pete Wass
11-17-2010, 10:09 AM
Ok I have been visiting with two who will remain un named benchrest gunsmiths. I have guns from both of them. One is as I would expect very precise indicates the bore in to within .0001. The other say most all barrels are as he puts it crooked as a chicken wing, says the reason people use a floating reamer is so the crooked bore dont break there reamer. He tells me he simply puts the barrel in his good 3 jaw chuck and runs the reamer in. Also says he dont use no coolant flush system never has, just dip your reamer in cutting fluid and let er go. As I said earler I have guns from both smiths and as you might have guessed it the latter out shoots the first. Why? Question are new barrels crooked if so how much? If so why do we try and set them up so close? Does it matter ? What matters and why?

Did you REALLLLY have to ask this question?

bdotson
11-17-2010, 10:44 AM
Did you REALLLLY have to ask this question?

"Yes" how else would someone learn. Sorry if my question is so stupid it offended you. I am no gunsmith however I have been around some machine work and find .0001 very hard to work with. I have never had a 3 jaw chuck that will run at .0001 . Yet I have seen many rifles being chambered with 3 jaw chucks. The way I understand it If you are going to hold .0001 "total" your chuck would have to be true to .00005. provided you reamer has zero runout. I have a intrest in chambering my own rifle and therefore have questions as to how critical this is. again sorry if I offend you.

JonathanK
11-17-2010, 11:35 AM
Im pretty sure you are talking about "Dialing in" vs. "between centers" styles of chambering. As I understand it, setting up "between centers" just uses the headstock and a dead center

Pete Wass
11-17-2010, 11:44 AM
"Yes" how else would someone learn. Sorry if my question is so stupid it offended you. I am no gunsmith however I have been around some machine work and find .0001 very hard to work with. I have never had a 3 jaw chuck that will run at .0001 . Yet I have seen many rifles being chambered with 3 jaw chucks. The way I understand it If you are going to hold .0001 "total" your chuck would have to be true to .00005. provided you reamer has zero runout. I have a intrest in chambering my own rifle and therefore have questions as to how critical this is. again sorry if I offend you.



I guess it seems so elementry to me that if one wanted to have a machine made that would render exact results one would want an exacting craftsman to build it is all. I am not offended in any way but think the answer should be obvilous.

There are three jaw chucks called "Set True" or other names such as that which permit one to center work held in them to zero. The chuck itself is held on a plate that provides the ability to move it around whilst having an item chuclked up in it.

I visited a local new gunsmith a few months ago. I asked him if he could chamber Benchrest Quality barrels. He told me he could and held everything to .001" or less but it was obvious to me that he thought .001 was very close work. Perhaps it is for a "Consumer Rifle" but for my standards "0" is what I am looking for, if I can get there.

bdotson
11-17-2010, 11:58 AM
I guess it seems so elementry to me that if one wanted to have a machine made that would render exact results one would want an exacting craftsman to build it is all. I am not offended in any way but think the answer should be obvilous.

There are three jaw chucks called "Set True" or other names such as that which permit one to center work held in them to zero. The chuck itself is held on a plate that provides the ability to move it around whilst having an item chuclked up in it.

I visited a local new gunsmith a few months ago. I asked him if he could chamber Benchrest Quality barrels. He told me he could and held everything to .001" or less but it was obvious to me that he thought .001 was very close work. Perhaps it is for a "Consumer Rifle" but for my standards "0" is what I am looking for, if I can get there.

Agreed I cant see any gun "not" shooting because the gunsmith was to perfect.

Gene Beggs
11-17-2010, 12:00 PM
In my opinion, Gordy Gritters in his video,

"Chambering A Championship Match Barrel"

explains it better than anyone. Although I do not chamber in the headstock, I have my own method of accomplishing the same thing. I will say this,

"Proper fitting, chambering and indexing of the barrel is far more important than most realize. In my opinion, the barrel makers are actually making a lot more "Hummer" barrels than they get credit for.

When I first got into benchrest over twenty years ago, I always heard that if one got his hands on a "Hummer" one out of twenty times, he was lucky and that the vast majority of new barrels would prove to be mediocre at best.

With experience and especially afer I began doing my own gunsmithing over seven years ago, I now believe that many of the "Hummers" are due to the skill of the gunsmith who installed them. Now don't get me wrong, I know there are bad barrels that just won't shoot no matter what you do but I do not believe there are as many as some believe.

FWIW


Gene Beggs

Pete Wass
11-17-2010, 12:44 PM
In my opinion, Gordy Gritters in his video,

"Chambering A Championship Match Barrel"

explains it better than anyone. Although I do not chamber in the headstock, I have my own method of accomplishing the same thing. I will say this,

"Proper fitting, chambering and indexing of the barrel is far more important than most realize. In my opinion, the barrel makers are actually making a lot more "Hummer" barrels than they get credit for.

When I first got into benchrest over twenty years ago, I always heard that if one got his hands on a "Hummer" one out of twenty times, he was lucky and that the vast majority of new barrels would prove to be mediocre at best.

With experience and especially afer I began doing my own gunsmithing over seven years ago, I now believe that many of the "Hummers" are due to the skill of the gunsmith who installed them. Now don't get me wrong, I know there are bad barrels that just won't shoot no matter what you do but I do not believe there are as many as some believe.

FWIW


Gene Beggs

Good Day Gene,

I agree with you on Gordy's video. I have one and have watched it a couple of times. I have geared up to begin doing my own barrels but haven't found the Intestinal Fortitude to do one yet :)

Charles E
11-17-2010, 03:08 PM
Question are new barrels crooked? Usually, some.


if so how much? "How much" is less important than "how quickly"


If so why do we try and set them up so close? Does it matter ?

See the answer to (2). Trivially, if a chamber is off-center to the bore, the bullet gets a sudden jolt when fired. Probably it will be deformed, but how could anyone prove this? Find a way to recover bullets with no further deformation?

On the other hand, if the deep hole drill wandered a bit, the barrel is "crooked." Very few of those wandering are a sudden turn . . .

bdotson
11-17-2010, 05:17 PM
Thanks to all who have replyed. I have an intrest in doing a barrel for myself someday so the questions. We all know a carpenter could use a set of mic's to build a house but cutting 2x4s to the .001 is a little overkill when buildng a house agreed ? The house will just as good, might be a little better but you wont see a noticable improvment in performance of the home. Now I dont want my home builder useing an axe or a chain saw so..... This brings the question when setting up a barrel that we know has some run out how close does it need to be to performe at its best?

Charles E
11-17-2010, 05:48 PM
This brings the question when setting up a barrel that we know has some run out how close does it need to be to performe at its best?

To know the answer to that, given all the variables -- which would need to be quantified -- would require a lot of testing. Only the military could afford that, and they have no reason to.

What we all settle for is *about* .0002 indicated. Can't prove it, it is just a number that's generally accepted. If it helps you fine.

Joe Duke
11-17-2010, 10:14 PM
In building a rifle, you might just jam the reamer in the barrel and get lucky once in a while. Heck, you just might even get lucky twice. To build highly competitive rifles in todays world you better be lucky every time. And that is not really luck, it is strict attention to all the details and making sure each one gets done correctly. The guy that sets everything up just right is going to win out in the long run.

joe

Pete Wass
11-17-2010, 11:35 PM
Thanks to all who have replyed. I have an intrest in doing a barrel for myself someday so the questions. We all know a carpenter could use a set of mic's to build a house but cutting 2x4s to the .001 is a little overkill when buildng a house agreed ? The house will just as good, might be a little better but you wont see a noticable improvment in performance of the home. Now I dont want my home builder useing an axe or a chain saw so..... This brings the question when setting up a barrel that we know has some run out how close does it need to be to performe at its best?

Would you trust a Home Builder to remove a tumor from your brain? Might do it ok, might not but do you think you would function as well if the Builder had used his Skill Saw to open your scull? Probably not, eh? Why there is special training and exacting tollerance levels for specialized fields.

This may be a better analogy for you to consider