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waksupi
10-07-2006, 12:36 AM
I learned a new tip from John King today. If you don't know, you can check a barrel for straight, by looking through it, and observing the light rings. They should appear concentric throughout the length, without running to one side of the barrel.
John showed me to decap a cartrige, and insert it into the chamber. This focuses the light entering, and makes the light bars much easier to observe.

felix
10-07-2006, 10:17 AM
Great idea, Ric! I don't think I want to check my barrels. Might make me think I have more junk than I already have. Besides, this is a board of folks who thrive on making junk pieces pass the class with grade "B" or better. ... felix

montana_charlie
10-07-2006, 05:18 PM
The thing is a bent barrel that is not known to be bent, always will be.
A bent barrel that is known to be, can be straightened. It is a regular occurence during the manufacture of barrels.

True, straightening one which has already been rifled would be a bit trickier than one which has only been bored. And having the 'eye' and the 'touch' to do a good job...well...that's where the 'adventure' comes in.

Four Fingers of Death
10-07-2006, 10:15 PM
The museum at the Small Arms Factory at Lithgow has a section on this inclding the stands, etc that the guys used. They have posters of what the barrels should look like. I will probably work as a voulenteer there when my retirement comes through. Mick.

montana_charlie
10-08-2006, 12:09 PM
Marlin rifles have had a reputation for many years of being good shooters...while not being high-priced guns. I have heard that the primary reason for the reputation is the talent of the old guy who always did (maybe still does) the barrel straightening for them.
CM

versifier
10-08-2006, 09:22 PM
Having done it for a living, I can tell you two things. First, it makes no difference if it has been rifled or not, the optical illusion of concentric rings is the same, if you can see it. Second, not everyone can see it. I don't know why, maybe the shape of the eyeball, certain strengths or deficiencies in color vision (I see it as a rainbow if the light source is sunlight, or pinks and blues if flourescent), or what you ate back in the 60's[smilie=1: . One thing that bears on it is that some people cannot easily change the focus of one eye alone over distance, but others do it instinctively. You would think that rifle shooters would find it easier than non-shooters, but that wasn't always the case.

Ric, the idea of using the flash hole is a stroke of absolute genius! It's one of those: "DANG, I should have thought of that" ideas. All the barrels I worked on were unchambered, many m/l's, but a set of decapped shotshells should work for bigger barrels

It takes a bit of practice to be able to use the straightening press on the right point of the barrel, but we were started out on .54 & .58 cal barrels and graduated to smaller ones as we got used to it. The unit was WWI vintage and looked like a cross between an overhead-mounted ship's steering wheel and a medieval torture device, but it sure worked slick.

45 2.1
10-10-2006, 07:26 AM
Its just about as much fun to bend a shotgun barrel to get the group hitting where your looking. I did that for an old long barreled Ithaca 37 some time ago, without the bending device.

versifier
10-10-2006, 10:00 AM
I kinda don't think it would work too well on a thin walled shotgun barrel.
About the thinnest I ever tried on it was those old H&R break action m/l's with the o-ring gasketed "suicide breechplugs". A good friend had three of them and not a one was even approaching straight. It took a whole lunch break to do each one, and I was worried the whole time about kinking or denting them. They shot noticably better afterwards as far as POA vs. POI. Recrowning got them much more accurate. Back then, they were the only m/l's you could use on a rainy day and have a hope of them actually going off when you pulled the trigger. But you had to remember NEVER to open them after a hangfire. I didn't trust them at all, but he shot a lot of deer with them over the years.

Char-Gar
10-10-2006, 11:34 AM
Elmer Keith used to make much about being able to peer down a rifle barrel and tell if was straight, crooked or had been straightened. I have no doubt he could do that, but I can't and have tried many times.

IIRC Keith also contented that a straightend barrel would not shoot quite as well as one that was straight to start with. The theory being , as the barrel heated, it wanted to go back to it's original shape.

I have no idea what the truth is, just what I read back in the Days of Yore!

montana_charlie
10-10-2006, 11:37 AM
Having done it for a living, I can tell you two things. First, it makes no difference if it has been rifled or not, the optical illusion of concentric rings is the same, if you can see it.
Now, there's a good example of how book learning differs from actual experience.
While I've never straightened a barrel, I thought I was pretty well-informed on the subject.

I thought the 'concentric ring deal' was an adaptation for rifled barrels, because the 'broken line thing' (while preferred) would only work on bores that were still smooth.
CM

mhb
10-11-2006, 12:38 PM
FWIW, barrels made in our shop are never straightened - the entire process is designed to produce a straight drilled and reamed blank - any which are NOT straight after reaming are never finished, or leave the shop. IF one had to straighten a barrel, the only correct time to do so is before it is rifled - any straightening done later is a makeshift. The problem with straightened barrels is that the induced stresses cause the barrel to 'walk' as it heats up from repeated firing, and, while this might not be a severe problem in a hunting rifle which is never fired more than, say, three shots in a fairly short time, it is not desireable in a barrel intended for high accuracy applications, where the requirement is to group a series of shots as closely together as possible. In this respect, the cut-rifling process offers advantages, because the barrel can be stress-relieved before any machining is done on the bar, and the blank turned to near-final outside dimensions before final reaming or rifling - typical bore TIR from end-to-end of a 30" blank so handled is less than .010", and subsequent external operations are done between centers on the bore itself: this makes for a straight, stress-free barrel, and avoids inducing further stress by turning a full-diameter blank after reaming and rifling (as must be done with buttoned barrels).
While we have an overhead barrel straightening jack, it has never been used on one of our barrels - only on the occasional bent barrel (some fairly severe) brought in on customers' commercial or milsurp rifles.
So far as shotgun barrels go: I noted long ago that trapshooters, in particular, are nuts, and will do whatever they think will gain them an extra bird - I watched a guy take the barrels off his Perazzi, walk up to a tree, and whack the barrels against it to bend them slightly upward, as he thought he was shooting low!
mhb - Mike

45nut
10-11-2006, 01:25 PM
Mike,,
Are you the maker behind Morrison Barrels?
If so could you email me a link or maybe a basic price list via email?
I did a search and your work is highly regarded it appears.

KCSO
10-12-2006, 05:08 PM
MHB
You got it!
That was Harry Pope's method, if it ani't straight to start with start over. That said on the cheaper factory guns some times the barrels aren't straight. That's when a man with the right eye for the job can make an improvment. For muzzleloaders, where the barrel will not heat much straightening can do wonders. I use a press and special blocks to do the job in the shop, but i have used a tree crotch to save a deer hunt. I got the rifle back to wher it would hold 3 shots in 4" at 100 yards and back to poa after a truck drove over it. We did replace the barrel when the hunt was over, but that bent tube did get a deer.