quote:

Originally posted by craigster:
As far as I can tell from this thread, the only guys that know about the pros and cons regarding recontouring a rifle barrel (new or used) are those who have had it done and seen the results or those who have done it themselves.

I couldn't agree with you more. I don't know a thing about it, which is why I was asking questions. The main problem is that those who, as you suggest, know, (e.g. those who have had it done and those who have done it) DON'T seem to agree on what they know!

My gunsmithing experience is zero and I only have one recontoured barrel, a 52 standard target that was turned down to a sporter, it shoots fine but I never shot it in its original form so I have no idea if it is better or worse. What I am about to write are my impressions from reading a lot of recent articles in Precision Shooting. When you turn down a barrel, reducing its diameter as you go towards the muzzle, the bore will expand towards the muzzle. According to the PS writers, this is exactly the reverse of what you want: the bore should taper slightly from breech to muzzle. If it gets bigger the bullet gets loose in the bore. In theory, this gradual expansion will happen in simply turning down a blank the first time. Usually the difference isn't enough to matter to anyone except a bench rest competitor. But in principal evidently all barrels should be turned to final contour before they are bored, rifled and lapped - and the lapping should be done very carefully so that the bore is tighter towards the muzzle. This is said to be especially important with .22 rimfire.

There is some good info in this thread and I have an example of what CAN happen. When I rebarreled my first rifle, I wanted to do it all, so I ordered a select match stainless blank from Shilen for a 280 Ackley I wanted to build. The order at which things were done, and my methods may not have been perfect, but I turned that blank down to a 26" med hvy sporter taper and fit it to a M70 action and chambered it up. The turning of the barrel was interested in the least as I didn't know a whole hell of a lot and didn't even use coolant. There was some induced stress on that sucker and although it shot OK, she walked a bit. Well I had it Cryoed by Badger Cryogenics near here in Baraboo, WI, and it settled down very well. Wouldn't shoot heavy bullets very well due to twist and a harmonics issue I'm thinking, which pissed me off a bit, so one day at the range I was shooting some 100 gr something or others and shot a 5 shot group well under 1". I thought to myself, OK you SOB, let's see if you'll hold that and I fired another 10 shots pretty much as fast as I could load and squeeze. 15 shots in 1 1/4" was the result and the heat was just rolling off the tube.

I guess if there IS a stress issue from a dumbass like myself hogging off too much metal too rapidly, there IS a fix in using the cryo process. I've also used it on a M70 featherweight barrel of my dad's that walked over 6" after 3 shots and that one settled down in to a true MOA shooter for five rounds and didn't walk a bit.

I know that ONE instance isn't close to the experience many have, but that's mine, and I'm sold on Cryo'd barrels for those specific instances. Also for those who are interested, those barrels turned into some of the easiest cleaning tubes I have. They don't foul nearly as bad, and clean up in a snap.

It might be helpful to compare what is being discussed here with wooden stocks.

As most people know or have read, the grain flow in the forearm of a blank “can†have an effect on how the wood “may†move when being turned into a finished stock.

Sometimes it moves, sometimes it doesn’t. Sometimes it moves allot, sometimes it moves very little.

The point being that a rational person at least considers this when picking a blank since there really isn’t any reliable way of knowing what “might†happen when the wood is thinned in the forearm/barrel channel before hand.

All jokes and arguing aside, I don't think anyone here is saying it's a given that a recontour job is a 100% lock for success. I think it's obvious though that enough people have had success that for them it's a risk worth taking. Like most things there is risk and it's a simple evaluation whether or not a person wants take it. I've had two done, one was great, the other was a train wreck. The train wreck was also done very, very poorly, the barrel looked like it had growth rings. Would this barrel been more accurate if done by a better machinest, one can only speculate as the work can't be undone. The barrel that turned out well was contoured to fit a older stock whos original barrel had the hump for the rear site. I liked the stock so I had the barrel turned to fit. The finish,shape and fit was well done, it also shoots fine. My conclusion is it does take skill. I don't know how anybody can argue against skill especially when it comes to a gunsmith or machinest.

Rick, you still aren't answering the question.

Several years ago, I bought a mess of barrels from Mark Stratton while at one of his classes in Trinidad. He'd bought them from the Apollo Arms (?? can't remember now) auction when they went out of business.

Anyway, most of them were in obscure calibers, weird contours and quite long for my tastes. Several of them were threaded for some large breeched benchrest rigs...all of them appeared to have been fired.

Anyway, to the point - I've since recontoured no less than five of them to a very light sporter weight. As I don't have a taper attachment for my lathe, I was offsetting the tailstock and cutting between centers. I found that making cuts of less than .005 seemed to be the hot ticket on my little 10" Clausing, anything more than that I was getting a lot of chatter, and it seemed like the barrel was getting hot a lot quicker as well. I was using compressed air spraying on the workpiece as a coolant medium.

Since I was cutting between centers, the last 1.5" or so, where the lathe dog was, didn't get cut. Wasn't a problem, as I wanted the barrels shorter anyway. Would have been interesting to check with a lead lap, if you could feel any bore dimension change before and after...

Not sure that it would be economically feasible for a shop(using the same setup as I) to spend that much time doing it, but every one of these barrels has been a shooter, but it took me several hours to get them where I wanted them.

quote:

Originally posted by Chuck Nelson:
Rick, you still aren't answering the question.

You know I checked my list of things I give a Rat’s Ass about, and I hope this doesn’t hurt your feelings, but you weren’t on there.

Well, could we take that as a "I haven't got a clue but will give an opinion anyway".

What else don't you know that you could give an opinion on. Makes for interesting discussion.

quote:

Originally posted by vapodog:

quote:

Originally posted by malm:

quote:

Originally posted by vapodog:

quote:

If you remove more material from the INSIDE (ie - reboring) would that not also cause potential problems?

IMO no it won't. That is of course no significant heat is incurred.....one must use sharp tools and a reasonable coolant.

Even button rifling is insignificant in producing stress.....it does....but small. Further any stress involved is symetric to the bore and will not cause trouble.

Button rifling is similar to "express tapping" or thread forming where the tap used does not cut the thread but actually pushes material to form a thread.

I've never found any issues related to stress in the materials using these taps.....from this I assume that button rifling incurrs minor stress at the best.

Machining does not produce stress.....it relieves it when the stress is already present in the steel and causes the material to bow...look like a banana.

Reboring and rifling an existing barrel is not at all likely to create any stress that is noticeable to anyone.

There you go Bill! Any other questions???

Malm...if you have a differing opinion feel free to post it....it's a lot better than to just look like an asshole!!!!

Vapo, I'm surprised you didn't know this a long time ago.....many of the rest of us knew it months ago. You're catching on but slow.

quote:

Originally posted by duikerman:
Vapo, I'm surprised you didn't know this a long time ago.....many of the rest of us knew it months ago. You're catching on but slow.

Duiker: "a tiny, shy antelope with males having short horns."

That probably sums it up.

This was forwarded to me to pass on. I believe it is appropriate for this thread...

quote:

From page 163 of Volume 1 Brownell's Gunsmithing Kinks:

"One of the main obstacles in barrel turning is warpage or distortion. Many authorities
will credit this to the heat generated by the turning process. However, a barrel which
contains stresses will warp, regardless of how cool it may be kept, so it is imperative
for the gunsmith to obtain blanks that are made from a material that is absolutely
stress-free."

- P.O. Ackley, Salt lake City, Utah.

Guy, yeah well what does he know.

Ok here is my 2cents worth. I have done this twice. Started with blanks, one a standard grade chrome-moly douglas and one stainless match shilen. I contored, chambered and shot them, then decided I left them too heavy. So I turned them to a smaller diameter. All this was done with coolant and light cuts. I didn't see any change in accuracy. I still have both of these today. In fact on the shilen I re-contoured then fluted it. I have also bought 2 barrels that were already contoured then turned them to match and replace factory barrels and according to the guys that have them they also shot fine. I'd do it again depending on the circumstances.

quote:

Originally posted by kwk:
Ok here is my 2cents worth. I have done this twice. Started with blanks, one a standard grade chrome-moly douglas and one stainless match shilen. I contored, chambered and shot them, then decided I left them too heavy. So I turned them to a smaller diameter. All this was done with coolant and light cuts. I didn't see any change in accuracy. I still have both of these today. In fact on the shilen I re-contoured then fluted it. I have also bought 2 barrels that were already contoured then turned them to match and replace factory barrels and according to the guys that have them they also shot fine. I'd do it again depending on the circumstances.

FWIW, from the Shilen web site:

What about "fluting" a barrel?
Fluting is a service we neither offer nor recommend. If you have a Shilen barrel fluted, the warranty is void. Fluting a barrel can induce unrecoverable stresses that will encourage warping when heated and can also swell the bore dimensions, causing loose spots in the bore. A solid (un-fluted) barrel is more rigid than a fluted barrel of equal diameter. A fluted barrel is more rigid than a solid barrel of equal weight. All rifle barrels flex when fired. Accuracy requires that they simply flex the same and return the same each time they are fired, hence the requirement for a pillar bedded action and free floating barrel. The unrecoverable stresses that fluting can induce will cause the barrel to flex differently or not return from the flexing without cooling down a major amount. This is usually longer than a shooter has to wait for the next shot. The claim of the flutes helping to wick heat away faster is true, but the benefit of the flutes is not recognizable in this regard until the barrel is already too hot.

Rick

Once again, then why would a guy like David Miller flute his Marksman Rifles, which I believe now sell for about $10,000 a copy.

quote:

Originally posted by 22WRF:
Rick

Once again, then why would a guy like David Miller flute his Marksman Rifles, which I believe now sell for about $10,000 a copy.

22WRf,

Thanks for the compliment, but those weren’t my words. They came from the Shilen web site and concerned their policy on their barrels...I just passed it along for his consideration. That’s why I prefaced it with For What It is Worth (FWIW). His decision to make!

No one, including me, has said that it is impossible to contour, re-contour, or flute a barrel and have it turn out fine. All that a couple of us have said is that the POSSIBILITY exists that no matter who does the work or how talented and careful they are, problems MAY occur due to unknown stress being released when the barrel steel is thinned. None of us said that it was a definite result...we just said that it could and has happened.

If a guy wants to take that chance then more power to him, but some of us just thought that before embarking on such a project you should have all the good and bad scenarios at your disposal in order to make an informed decision.

Some guys have posted that they have had no problems with it (and I don’t doubt them)...some others have posted that they have (and I don’t doubt them either). It’s up to you to decide what you want to do with YOUR rifle and YOUR barrel.

If you don’t want to hear all the answers and opinions (or if you have already made up your mind) then don’t ask the questions in the first place. That’s pretty simple isn’t it?

quote:

Originally posted by 22WRF:
Rick

Once again, then why would a guy like David Miller flute his Marksman Rifles, which I believe now sell for about $10,000 a copy.

Duh, because that's what the customer wants. And for $10K, they probably get what they want. That's my opinion. But, if you really must know, then friggin call David Miller and ask instead of fomenting more arguement here. Rick gave you his opinion not David's.

Rick and Poleax

Last time I looked Saeed owned this site, so I don't understand where either of you thinks they can tell me "don't ask the question in the first place" or don't foment arguments here.

If you will read all of my threads here, not once did I call anyone names, or imply that people were stupid, etc. Yea, I asked some tough questions, but so what.

I would suggest that if neither of you feel comfortable in carrying on a civil discussion it should be you that refrains from posting.


The good thing is that in spite of everything I did get a lot of real good information, and now I can go ahead and make my decision as to what to do next.

quote:

Originally posted by 22WRF:
Rick and Poleax

Last time I looked Saeed owned this site, so I don't understand where either of you thinks they can tell me "don't ask the question in the first place" or don't foment arguments here.

If you will read all of my threads here, not once did I call anyone names, or imply that people were stupid, etc.

I would suggest that if neither of you feel comfortable in carrying on a civil discussion it should be you that refrains from posting.

Excuse me, but when malm (a fulltime working gunsmith with years and years of barreling experience) mentioned a “trained eye†for checking the straightness of a barrel how did you respond to him??? Go back and read what you posted.

“ 22WRF
one of us
Posted 21 May 2006 21:31
Malm

what university did you send your eyes to in order to get them trained?“

Does the term “passive-agressive†ring a bell here? You insult people and just because you do it without bad language that makes it okay in your book?

Rick

I consider you a very intelligent man and so you know what I meant when I said what I said to Malm. In retrospect, I should have said it differently, and I appologize to him now. What I should have said is that eyes don't get trained. Any eye would see the malady. It would be his "experience" gained through measurement, shooting, etc. etc. to know what his eye saw, not the training of his eye.

Sorry Malm.

quote:

Originally posted by 22WRF:
Rick

I consider you a very intelligent man and so you know what I meant when I said what I said to Malm. In retrospect, I should have said it differently, and I appologize to him now. What I should have said is that eyes don't get trained. Any eye would see the malady. It would be his "experience" gained through measurement, shooting, etc. etc. to know what his eye saw, not the training of his eye.

Sorry Malm.

Hey, malm and I both are big boys and we don’t “break†real easy!

I’m just your average self taught gun-butcher like most of the other people posting on here, but malm knows of what he speaks when it comes to all around gunsmithing and he is one of the few people posting on here that does it fulltime and has worked on just about every type of rifle out there. I have learned a bunch from him just through emails and phone calls.

Well this thing has about come full circle. We're no closer today than we were after the first reply. Had this thread ended then, we could have prevented a lot of this. Doesn't appear that we've come up with any definitive answers to the question. Which is probably right since like life, nothing is certain. I for one am ready to hop off of this one before I have an Oprah moment.

I have used several Lilja barrels and have ask Dan to re-contour a barrel for me. It is no big deal as Dan has a contour lathe. Didn't do anything to the barrel but make the contour different.

quote:

Originally posted by Pegleg:
I have used several Lilja barrels and have ask Dan to re-contour a barrel for me. It is no big deal as Dan has a contour lathe. Didn't do anything to the barrel but make the contour different.

Pegleg

I hear ya. But the difference is that both Rick and Malm know I am a cheap S.O.B. so they know I don't use Lilja barrels.

Rick you're right that is what the shilen website says, I read it too and spoke with someone at shilen a couple different times about fluting. I don't question the knowledge at shilen but in my personel experience I haven't seen a problem with fluting their barrels or any other barrel. I do believe the possibility is there to revieve stresses in the steel and adversly effect accuracy. It's simply a chance I'm willing to take because I like the look of fluted barrels.Fluting has been beat to death here many times and like a lot of things you can ask 5 different people and get 10 different opinions.