I have been discussing the regulation of the barrels of a double rifle, and hear some conflicting information. One gunsmith tells me that in order to regulate the barrels to shot the same point at 50m, barrels bust be bent. Another said that a quality made gun should have the same POI without ever needing to have any bend in either barrel.

What can you tell me about this? Would high end double rifles from Holland and Purdey and WR have bent barrels?

Bending to me would be like the Sabatti cutting the crown.

I'm sure not an expert but I thought the barrels were regulated with spacers and then after they were shooting together the rib was then installed.

http://www.theexplora.com/regu...at-westley-richards/

Negative on the bending. A wedge is utilized and it is the placement of the barrels parallel to each other utilizing a wedge for barrel placement to achieve proper alignment and bullet placement.

A reputable maker would never accept a bent barrel. Metal has memory and a bent barrel would theoretically walk or string it's shot placement at higher temperatures caused by firing the rifle.

At least I read that on a box of Cherrios.

Dutch

quote:

Originally posted by Dutch44:
Negative on the bending. A wedge is utilized and it is the placement of the barrels parallel to each other utilizing a wedge for barrel placement to achieve proper alignment and bullet placement.

A reputable maker would never accept a bent barrel. Metal has memory and a bent barrel would theoretically walk or string it's shot placement at higher temperatures caused by firing the rifle.

At least I read that on a box of Cherrios.

Dutch

I know you and most everyone here read everything they know from there.

It comes down to a number of things, most doubles have some degree of bend unless the bores from breach to muzzle were set at a perfect angle from the get go...if that makes sense.

Depending on how far back on the barrels the regulator gets the solder flowing during regulation dictates the degree of bend. So if you only move the first 6" .030" apart at the muzzles the degree of the bend will be tighter than if you moved the barrels the same distance apart but did it in 12" of barrel length. By definition this is bending since the rest of the barrels aren't being altered/moved during regulation since solder isn't flowing. The amount of bend we are talking about is pretty minimal.

This isn't to be confused with laying the barrels over an anvil and whacking them with a hammer.

Aaron,
Assuming the breech anchored in place then I would agree that adjusting the barrel muzzle up/down and side ways could be called bending.

Just not the first thought that crosses my mind.

I have a picture of a old smith I knew about 40 years go as he placed a barrel (shotgun as I remember) in his jig and leaned against it until he felt it was straight.

quote:

quote:
Originally posted by Dutch44:
Negative on the bending. A wedge is utilized and it is the placement of the barrels parallel to each other utilizing a wedge for barrel placement to achieve proper alignment and bullet placement.

A reputable maker would never accept a bent barrel. Metal has memory and a bent barrel would theoretically walk or string it's shot placement at higher temperatures caused by firing the rifle.

At least I read that on a box of Cherrios.

Dutch


I know you and most everyone here read everything they know from there.

Truer words were never spoken, Shit-a-way. I understand this is the same box of Cherrios that you viewed to distinguish the male and female species of bovine (that's buff to a canuck).

Dutch

I don't know why any of us, me included, read, write, or ask on AR anything about doubles. Why don't we just PM Shootaway for an honest and accurate answer? From his hunting and marksmanship skills, to his choice of the finest bespoke double rifle, he is the master. There is really no on else.
Below some words to the great one.
Cal

Cal,

Did you happen to know that there was a rap song written about Shtizaway?

THE BADDEST OF THEM ALL!!!

https://www.youtube.com/watch?v=XArx0ASwyDc

quote:

Originally posted by surestrike:
Cal,

Did you happen to know that there was a rap song written about Shtizaway?

THE BADDEST OF THEM ALL!!!

https://www.youtube.com/watch?v=XArx0ASwyDc

Oh, thanks surestrike, I just added to that kid's view total. 1.48 million and counting.

WhereTF did you find that?!

Cal:
That Uncle Sam poster is the tits! Wish I had one for my office.

Dutch

In spite of Sheetferbrains, Ramrod, thx for putting up that site, interesting reading there.

I love seeing the way they regulaste the barrels, thanks.

Looks positively medieval

I was wondering if the double we see Stuart pictured with is an old WR or a new one.It is very pleasant looking with perfect stock shape,IMO.

quote:

Originally posted by A7Dave:

quote:

Originally posted by surestrike:
Cal,

Did you happen to know that there was a rap song written about Shtizaway?

THE BADDEST OF THEM ALL!!!

https://www.youtube.com/watch?v=XArx0ASwyDc

Oh, thanks surestrike, I just added to that kid's view total. 1.48 million and counting.

WhereTF did you find that?!

If you google dumbest mf'er on the planet and shootaway in the same search engine. That is the theme song that pops up.

quote:

Originally posted by Brian564:
I have been discussing the regulation of the barrels of a double rifle, and hear some conflicting information. One gunsmith tells me that in order to regulate the barrels to shot the same point at 50m, barrels bust be bent. Another said that a quality made gun should have the same POI without ever needing to have any bend in either barrel.

What can you tell me about this? Would high end double rifles from Holland and Purdey and WR have bent barrels?

The regulating of a pair of barrels to shoot properly is a very complex activity that is done by very skilled people. While the final adjustment is done by one person who manipulates the wedges in microscopic movements of the barrels at the muzzle end of the barrels. Movements so small that the difference the movements made have to be detected with a micrometer, and cannot be seen with the necked eye. Yes, the barrels are warped to a microscopic amount so small you can look down the barrels and cannot see the so-called bend. Actually most production single barreled rifles will have seemingly straight barrels but have bores that are not truly centered the full length of the barrel and even so have more curvature (BEND) in the bore than a double rifle.

SO! I guess you could legitimately say the barrels must be BENT to regulate but it is so slight over the length of the barrel that it cannot be detected with the naked eye, and it is a necessary condition to make the rifle shoot PROPERLY! A double rifle that is properly regulated will never cross the centers of each barrel’s individual four shot group! IOW they shoot parallel and build a working composite group of both barrels on the target. The movements done by the regulator are so tiny and that is the reason so few people can regulate a double rifle properly.

Though the line of sight through the barrels do cross, that doesn’t mean the shots from those barrels do, but, in fact, shoot side by side, because of the barrels movement during a thing called BARREL TIME, so that when properly regulated and shooting a regulating load each barrel will move UP and AWAY from the other barrel, so that each barrel is pointing to where the sights were pointing when the trigger was pulled.

. This may seem confusing but it isn’t once you understand the effect of recoil and barrel time has on each barrel to hit the target at a different place than where the barrel’s line of sight is looking before the trigger was pulled. When the right trigger is pulled with the sights aligned on the aiming point on the target the right barrel is pointing to a place on the target that is low, and on the left of the aiming point on the target . The barrel time (the time the bullet is traveling down the barrel from case to muzzle ) as the barrel being fired moves UP and AWAY from the other barrel to a point where it is pointing to where the sights were pointing when the trigger was pulled.


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I bow my head to you, gentlemen, for the wonderfully written and explained replies. The amount of experience here is astounding. I now have a new respect for double rifles and the men building these most sophisticated machines

As I recall when Kirk Merrington was showing me his regulation setup a few years ago, he said about one ten thousandth of an inch barrel adjustment yielded an inch at 100 yards. Seems I recall he was 'bending' the last 10-12" inchs of barrel length. Definitely an art...

Good hunting,

quote:

Originally posted by Brian564:
I bow my head to you, gentlemen, for the wonderfully written and explained replies. The amount of experience here is astounding. I now have a new respect for double rifles and the men building these most sophisticated machines

Brian, welcome to the wacky world of double rifles! They are the most misunderstood firearm in the world. As you have found here, the relative high cost of double rifles compared to machine made and assembly line made single barreled rifles is not because some are highly decorated, but because of the very skilled labor intensive method of manufacture for them even in the field grade doubles.

As dpcd says above the building of a double rifle is an art not just science. Because of that fact the cost of the labor is very high, and the people who can do this work are few and far between. There are thousands of very skilled machinists around, but that doesn't mean they are capable of making a double rifle that is worth owning.

Certainly every maker of today uses the CNC machines to do the HOG work that was done historically by shop appies to get the parts close to the final shape. The double rifle cannot be made with nothing but machines, but must be made to it's final fitting by very skilled human hands. The cost of the very expensive ammo alone needed to regulate a double rifle can run into several hundred dollars and the hand fitting and finishing brings to light the reason a field grade double rifle may take as much a a year to finish for shipment to the buyer. Double rifle simply cannot be made by machines, while most single barreled rifle can, hence the difference in cost! With the very high cost of skilled skilled labor required to build a double rifle, it is a wonder to me that they are as cheap as they are!

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Actually, with a 12 inch fulcrum, to move the bullet one inch at 100 yards needs slightly more than three thousandths of barrel movement (.0033). About the thickness of a hair. One ten thousandth is not enough to do anything.
I usually work in increments of ten thousandths (.010) and once I get it to within 2 inches at 50 yards, then fine tune it from there. That is the way you adjust artillery fire; bracket it onto the target.

quote:

Originally posted by dpcd:
Actually, with a 12 inch fulcrum, to move the bullet one inch at 100 yards needs slightly more than three thousandths of barrel movement (.0033). About the thickness of a hair. One ten thousandth is not enough to do anything.
I usually work in increments of ten thousandths (.010) and once I get it to within 2 inches at 50 yards, then fine tune it from there. That is the way you adjust artillery fire; bracket it onto the target.

I like your jig. Just wondering if finer thread might be more precise. Have you thought of adapting micrometer type adjustment to your system?
Bill

Maybe.....but this one works and I use dial calipers for measuring barrel width anyway. And I have calculated how much a quarter turn of the screws moves the barrels. If I did it every way, I might have spent more time on the fixture. Also remember that when you heat them up, the barrels grow quite a bit which makes it even harder to know how much you have moved them; remember the "art" part.

"Actually, with a 12 inch fulcrum, to move the bullet one inch at 100 yards needs slightly more than three thousandths of barrel movement (.0033). About the thickness of a hair. One ten thousandth is not enough to do anything."

Keep in mind that with barrels we're not talking about a hinged joint with a straight fulcrum for the 10-12" (or whatever) being bent. Bore centerlines at the muzzle will be converging more than a straight calculation suggests. Lots of factors come into play including stiffness affected by bore size and wall thickness, wall tapers, wedge location, etc. Definitely an art dealing with all those and other factors.

My hat's off to anyone with the skill and patience to take that process on...

Good hunting,

quote:

Originally posted by dpcd:
Here is the fixture I use for regulation; although I can move the barrels in any direction, in terms of precise increments (to the nearest thousandth of an inch), bear in mind that due to the barrel flip and jump mentioned above (those are tank gunnery terms), just because you move the barrel a certain distance, the bullet impact may or may not be exactly where you calculate it will be. Which is why regulation of double rifles is an art, not a science. And it requires patience. The last one I did was a 9.3x74 and it took at least 20 adjustments to get it into one inch at 50 yards. I mean I had to bend the barrels 20 times at least!

Excellent rig dpcd. I am in the proses of building my own, a bit different but will work too.

This thread is turning out to be very interesting, a lot of good valuable info.


Best regards

Malek
Good Hunting/Shooting and God's best.

quote:

Originally posted by Emory:
"Actually, with a 12 inch fulcrum, to move the bullet one inch at 100 yards needs slightly more than three thousandths of barrel movement (.0033). About the thickness of a hair. One ten thousandth is not enough to do anything."

Any movement will do something! Admittedly not much in the above case, but your measurement only indicates the change to the line of sight of a static barrel. It doesn’t take the effect of the barrel being flipped up and away from the other barrel into consideration. That is the reason simple measurements cannot predict the impact on the target, because no two rifles will be regulated properly with nothing more than a fixture that works like a pre-set JIG measured from another double rifle of the same weight and chambering that was properly regulated. Every rifle regulated in that pre-set JIG will shoot differently.

quote:

Keep in mind that with barrels we're not talking about a hinged joint with a straight fulcrum for the 10-12" (or whatever) being bent. Bore centerlines at the muzzle will be converging more than a straight calculation suggests. Lots of factors come into play including stiffness affected by bore size and wall thickness, wall tapers, wedge location, etc. Definitely an art dealing with all those and other factors.

My hat's off to anyone with the skill and patience to take that process on...

Good hunting,

Because simple measurements cannot be used to regulate a double rifle, because every double rifles regulated that way will shoot differently, and in most cases none will regulate properly. This is the reason SABATTI had so much problem with regulation. I suspect they tried to cut cost by regulating with a pre-set jig. That simply didn’t work, so they tried to salvage them with the Dremmel tool, which also didn’t work. this is why the ART of a talented regulator shows it’s worth!

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quote:

Originally posted by dpcd:
Maybe.....but this one works and I use dial calipers for measuring barrel width anyway. And I have calculated how much a quarter turn of the screws moves the barrels. If I did it every way, I might have spent more time on the fixture. Also remember that when you heat them up, the barrels grow quite a bit which makes it even harder to know how much you have moved them; remember the "art" part.

Yes I know what you are saying. The experience and skill of the operator can exceed the capability's of the tool.
Bill

quote:

Originally posted by Bill Cooley:
I like your jig. Just wondering if finer thread might be more precise. Have you thought of adapting micrometer type adjustment to your system?
Bill

Bill, it may seem like nothing more than semantics, but in the context of double rifle regulation, the word JIG indicated a PRE-SET frame that the barrels can be installed in and soldered up,without firing the rifle. The words ADJUSTMENT FIXTURE used here is a frame with six adjustment screws used to make adjustments while the trial and error manipulations of wedges combined with firing the rifle on target.

I know you understand this, but the word JIG gives the newbie the idea that a double rifle can be regulated in a JIG that was adjusted on a rifle of the same caliber that has been regulated, and soldered up without shooting.

The above is just one of the use of words that confuse people new to double rifles. The other is the word REGULATED for describing two different things by the makers. They use the word REGULATED to describe the physical manipulation of the barrels till they shoot properly on the target. Then they use the same word REGULATED for the sights ie: This rifle is regulated to 50 yds!! This second use of the word "REGULATED" has only to do with cutting the standing rear sight to be dead on for windage and elevation and to put the sights in the middle of a composite group of both barrels, at 50 yds. This use of the same word for two entirely different things by the maker leads new people to think the rifle is regulated to cross it's shots at 50 yds. You and I know that is not the case, but because the makers stated it that way the misconception is repeated time and time again.

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Mac, In this instance I was talking to someone who knows the difference. Perhaps a newbie might not know this JIG was used to control barrel movement and to reposition the barrels so that they can be soldered during regulation. The fault is in the process (not shooting to prove point of impact) not in the tool.
You missed one other important REGULATED. The need to regulate the ammunition to shoot to regulation in a particular rifle.
Bill

To further complicate things if one overtightens the wiring and or nails to hold down the ribs that can have effect on bullet placement. This is most prominent at the beginning when your movements are larger, and really comes into effect if in the middle barrel section that is being moved/adj is held stationary and not allowed to move with the muzzles.

As the barrels are spread apart the wiring/nails get tighter. If one doesn't fix this when it happens your adjustments will be less predictable the first go around. Then the next time you go to adjust the barrels will then "normalize" thus causing unintended bullet spread. Things will then settle down the third adjustment, unless you repeat the same mistake.

quote:

Originally posted by Bill Cooley:
Mac, In this instance I was talking to someone who knows the difference. Perhaps a newbie might not know this JIG was used to control barrel movement and to reposition the barrels so that they can be soldered during regulation.

Bill, I knew you, dpcd and Aron Little knew what these things meant, and that was my whole point in clarifying those points, for some of the newbies visiting on this very thread. Where you three are concerned I would be preaching to the choir by even mentioning it!

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Rather than "bend" would the proper term be "flex"?

Bend implies a permanent alteration of the metal. But if you took the solder off the rifle the barrel would unflex to its original shape.

This thread shows how little I know about doubles. I never thought the barrels were bent or flexed or whatever, but they were straight and set and a slight convergence for the regulation i.e. not parallel, and the regulating wedge just held the slight conference in place.
I learn something every day here.
Cal

Flex is a good way to put it because, yes, if you melt the solder, the barrels will return to their original positions.

quote:

Originally posted by dpcd:
Flex is a good way to put it because, yes, if you melt the solder, the barrels will return to their original positions.

Absolutely! I agree that the word BEND to me indicates a permanent and severe condition.

Flex is a far more descriptive word of what is done when regulating a double rifle!

This has always been a bug in my hat about the terms used leaving the wrong impression to the unschooled. These terms have caused a lot of people to totally misunderstand how a double rifle is made, or why they work to regulate two barrels to shoot parallel group centers forming a composite group of both barrels from converging barrels.

This is not just laymen but many otherwise fine gun smiths who do not understand double rifles either, and repeat those misconceptions themselves.

Threads like this one can do a lot to enlighten folks to the reasons that their first impression of double rifles was flawed because of things they read in magazines.

...................................................................

quote:

Originally posted by cal pappas:
This thread shows how little I know about doubles. I never thought the barrels were bent or flexed or whatever, but they were straight and set and a slight convergence for the regulation i.e. not parallel, and the regulating wedge just held the slight conference in place.
I learn something every day here.
Cal

Cal, I think you are right. The barrels are assembled to what is an approximation of where they should be for regulation. Most barrels were made and soldered up before being fit to a receiver sometimes by a different company. Then fitted to a receiver. Then after they are shot the front wedge and part of the rib is un soldered to move them by use of a jig or as Mac would prefer to call it a adjustment tool. Then re soldered and test fired. Repeat as needed. I believe the guys who did this a lot could get quite close on the first try. I also think you will find some barrels just don't like each other and it may take many attempts to get them regulated.
I agree with dpcd it is likely if you melted all the solder loose they would tend to return to the original location Because the barrels are made from tempered steel they will have a "spring back" or memory.
This is the most likely reason the Regulation JIG was invented. You hold the barrels in a known position then you can move one or both in a known manner and distance.
Bill

quote:

Originally posted by dpcd:
Actually, with a 12 inch fulcrum, to move the bullet one inch at 100 yards needs slightly more than three thousandths of barrel movement (.0033). About the thickness of a hair. One ten thousandth is not enough to do anything.
I usually work in increments of ten thousandths (.010) and once I get it to within 2 inches at 50 yards, then fine tune it from there. That is the way you adjust artillery fire; bracket it onto the target.

this is a very sound and logical method you are using here. I find it to be a very sensible approach to regulate a double one that I will use when time comes for me to work on regulating my rifles.

Question: is the fulcrum is the wedge used at midway point down the barrels. say if the fulcrum was 24" then is the adjustment going to be around .0066" in order to move the barrels one inch at 100 yards?


Best regards

Malek
Good Hunting/Shooting and God's best

Depends on the caliber, bullet weight, velocity, and recoil. There is no set equation or mathematics you can use to determine x barrel movement will equal a certain spread. one caliber may need more or less barrel movement then another to get the same result. At least in my experience.

Yes, in theory, but as Aaron said, there are lots of variables that enter into after the raw math is done.
But, once you move the barrels a certain amount and note the distance the bullets have moved, then that ratio can usually be repeated for that rifle only.

Both of you gentlemen are right each rifle/cartridge will act differently. and needs to be fine tuned accordingly. But generally it is the "rule of thumb" According to Ellis Brown in his book Building the double rifle he Gives a theoretically "rule of thumb" chart where in it he states that every .004" muzzles movement will cause a change of impact of 1" at 50 yds or (theoretically) 2" at 100 yds on a 24" barrels. which is close to the numbers dpcd indicated.


Best regards

Malek
Good Hunting/Shooting and God's best

quote:

Originally posted by Bill Cooley:
I believe the guys who did this a lot could get quite close on the first try. Bill

This is what I meant by my statement in one of my posts! Ie: “The barrels are put together by educated GUESS, for a starting point!” ! That is just the beginning of the regulation process. Unfortunately, IMO, that is the point where Sabatti stopped! That is what I meant about regulating with a pre-set jig only, and that will not work reliably!

My definition of a JIG , is a fixture that makes everything installed in it to be exactly the same! To explain this, they regulate one rifle in the traditional manor, then, to cut cost, place the barrels in a JIG, and adjust the JIG to the regulated barrels. Then the rest of the run of the barrels for that chambering is simply placed in the JIG, and soldered up, carded and fitted to the action and finished and sent to the buyer! As we found out with Sabatti, that doesn’t work very well.

The above is why I find fault with the term JIG in regulating a double rifle. As stated in posts above, we know what was meant by the schooled folks here, but when read without explanation by the newbie, it gives them the idea that regulation is not such a complicated process, so all the maker needs to do is use the JIG to cut cost to the buyer.

We know that is not the case and that the trail and error of shooting, then making adjustments in a ADJUSTMENT FIXTURE designed to make tiny adjustments till the rifle shoots properly. This cannot be done satisfactorily without shooting the rifle between adjustments.

quote:

Originally posted by dpcd:
Actually, with a 12 inch fulcrum, to move the bullet one inch at 100 yards needs slightly more than three thousandths of barrel movement (.0033). About the thickness of a hair. One ten thousandth is not enough to do anything.
I usually work in increments of ten thousandths (.010) and once I get it to within 2 inches at 50 yards, then fine tune it from there. That is the way you adjust artillery fire; bracket it onto the target.

The bold print in dpsd’s post above is the way all REAL regulators work, from the starting point (EDUCATED GUESS) , then fine tuning by firing and trail and error till the sweet spot is found.

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