Does any one have a nice list of the basic theories behind DR's ?
I have read Alexander Gray's book, Graeme Wright's book etc etc.
Has any one condensed the knowledge, theory into a nice concise list ?
For example, If your gun regulates with X bullet at Y velocity and you change to Z bullet:
1. If the bullet is lighter (less bearing surface) you generally have to decrease velocity to get it to regulate.
2. Lighter bullets have a tendancy to cross sooner at same velocity.
3. Heavier bullets have a tendecy ......
Just a thought.
It would be a nice reference of common theory.
Regards

Nitro450exp

I have found that lighter than standard bullets at lower than standard velocity will regulate.

But heavier than standard bullets are hard to regulate in my experience.

I have not found a provable relationship between bearing surface or bullet shape and regulation.

The one thing, to be sure, is not that just each rifle is different but that there are rifles that are picky and others that are not. This is the way it was put to me and my little bit of experience has validated it. What Dan said I have found to be true and also that slowing down the bullet (weight) that a rifle was regulated on is just fine. I think bullet shape and powder choice are huge considerations and that many have gone astray chasing a load to work up. I'm lucky, so far my Demas 470 digests anything that weighs 500 grns going over 2000 fps, this speed being an educated guess, but I've got the chrono now, a few diff bullets and one powder only but in 2 length cuts. This and 9.3 loads are current project.

Boy! Is this post going to open a can of wiggley worms!


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

There is my 75% Rule.

Once you have the proper powder charge for the full weight bullet, that regulates to the sights, you can substitute a bullet that is 75% the weight, use the same powder charge, and it should regulate and shoot to the sights.

This "Rule" has worked with 450/400, 450 No2, and several 470 double rifles.

With the 400's use a 300gr bullet.
With the 450 and 470's use 350gr bullets.

These 75% loads average @ 2330fps.

They give less recoil and a bullet more suited for smaller big game.

quote:

Originally posted by N E 450 No2:
There is my 75% Rule.

Once you have the proper powder charge for the full weight bullet, that regulates to the sights, you can substitute a bullet that is 75% the weight, use the same powder charge, and it should regulate and shoot to the sights.

This "Rule" has worked with 450/400, 450 No2, and several 470 double rifles.

With the 400's use a 300gr bullet.
With the 450 and 470's use 350gr bullets.

These 75% loads average @ 2330fps.

They give less recoil and a bullet more suited for smaller big game.

Also applies to 500 Nitro's with a 440gn Bullet

The only thing I am sure of is a whole lot of these old tales are purely BS!

I have seen too many doubles that shot about anything you stuck in them: I have seen them shoot much better than they are rumored to shoot; the stuff about having to shoot the front trigger first because they were regulated that way is pure bunk and I have never shot a double wherein that made one bit of difference in group size or point of impact; I don't believe that IMR-4831 blows up double rifles unless you over load them, I have just shot too much of it to believe that; and I know that most double rifles will shoot GS Custom FN monolithic bullets without any harm to the rifle..I am sure there are some more of these old wives tales, but can't think of anymore right off hand..

One thing I do believe and have seen happen is IMR-3031 will ring a barrel on ocassion with or without a filler, how often I don't know..

I have come to these conclusion from shooting double rifles for about 40 or so years, and I don't argue with anyone that believes otherwise as this is only my personal opinion.

I'd be interested in any other personal experiences, either way, that anyone has had. Not interested in what someone has read and passed on to others as that's how this stuff gets started...

Hello all,

Thanks for info so far, I have started playing with 325 and 400 grain gold dots over 5744, but I find it pretty dirty, so I am thinking about reloader or IMR. The accuracy of the 5744 loads was not great. I have a Kreighoff DR and it shoots the Federal stuff really well regardles of wether it is the woodliegh or TB Sledgehamer.
I have GS and woodliegh bullets, but don't want to waste premium bullets for just goofing. The Gold dots and blemished bullets from Midway are nice and economical. I will have to play some more and see if I can get them to shoot. Keep the theories coming
Nitro450exp.

nitroexp450

Try my 75% rule with your 325 and 400gr bullets.

For a load that kicks a lot less, try a notro for Black load.

With your same two Hornady bullets start with 48gr of IMR 4198 and 12 to 15 grains of Dacron polyester pillow stuffing. Just be sure the filler is compressed between powder and bullet.

Work up until they regulate and hit with the sights, probably somewhere around 50 to 60 grains of IMR 4198.
Velocity will be around 1700 to 1850 fps.

Amen Ray Atkins, spent 42 years as a gunsmith, the last 15 or 16 building doubles. I have never found any difference in the point of impact, whether holding your hand under the forarm or letting it lay on the rest. The only thing that makes a diff. is if you hold it on the side of a tree or post and its not that much if you hold the gun on the right side of the post when pulling the front trigger and vise-versa. Go a head all you experts throw the stones. Rich

Bullet & Speed and knowing where you started from is my key.

But I would love to see a "DEFINITION" of the word regulate , regutated and regulation in regards to a double rifle. because of all the experts and shoulders of steel seem to stumble on this simple idea or definition.

Think.... to unify the experts a 3-5 point common defintion that can be said in 15 seconds LOL.

My idea of regulation is to put a left and right into a 1.5in circle in relation to the sights at a chosen distance. Rich

quote:

Originally posted by nitro450exp:
Hello all, Thanks for info so far, I have started playing with 325 and 400 grain gold dots over 5744, but I find it pretty dirty, so I am thinking about reloader or IMR.

Amen on the 5744 powder, my 500 Heym will shoot about any bullet I put in it and I've taken loads with the same weight bullet (570 grain) and lower the powder charge 10% it still shoots very close to same POI with hunting loads.

Hunting load: R-15 88 grains 1/2 Kynoch wad, 570 grain bullet (540 grain GS solid)
Plinking load: R-15 80 grains full Kynoch wad, 570 grain bullet shoots 3/4 inch wider than hunting load stays parallel out to 100 yds.

I am going to try the Woodie 450 grain bullets and try the 75% rule, I'll let you know.

quote:

Originally posted by dirklawyer:
my 500 Heym will shoot about any bullet I put in it

I want a pic of you on your hunt next week walking on water. Of course, it will only work if you are actually carrying the Heym 500.

quote:

Originally posted by .500Pro:
Bullet & Speed and knowing where you started from is my key.

But I would love to see a "DEFINITION" of the word regulate , regutated and regulation in regards to a double rifle. because of all the experts and shoulders of steel seem to stumble on this simple idea or definition.

Think.... to unify the experts a 3-5 point common defintion that can be said in 15 seconds LOL.

I don’t know of any way to give a definition of that word in respect to double rifles that can be adequately stated in 15 seconds. This is because this word is historically thrown around for all sorts of different operations on double rifles.

I agree with 500pro on this! IMO, the word is used by the makers for two things, without explanation. This use of the word by the makers fosters a misunderstanding by those new to double rifles, or even to some who have been hunting with double rifles for years, and still do not understand how a double rifle works!

First the barrels being soldered in a converging physical format leads one to think the barrels are designed to cross at some point in the bullets flight. Then add the statement, by the maker, that the rifle is regulated at 100 Mtrs, and this seems to confirm the crossing!

Nothing could be farther from the truth! REGULATING the barrel convergence is one thing, and REGULATION at a distance is another entirely two different things.

#1 REGULATION of the barrel’s convergence is necessary because of a thing called barrel time, that is tied to the recoil induced movement of the barrels whit the bullet is traveling down the bore! This barrel regulation is done to match a load hat is known, and is known to be safe in the rifle. This is easier than working up a load to match the regulation already in the rifle.

This barrel convergence is because in a S/S double each barrel moves in opposite directions under recoil. The right barrel will move UP, and to the RIGHT under recoil, and left barrel will move UP, and to the Left under recoil. This means the barrels must converge, so that the barrel is pointing at the point of aim as the bullet exits the muzzles. To explain, with the sights on target at the POA when the trigger is pulled, neither barrel’s line of sight through the bore will be pointing at the POA, but will be when the bullet exits that barrel.

#2 REGULATION Of the sights are also called regulation, and is listed as @ 100 mtrs, or what ever distance! This doesn’t mean the bullets will cross at that distance, but that the the sights are in the center of a composite group of both barrels at that distance. The only relation to the group is that the sights are pointing to a point on the target that is half way between the CENTERS of each barrel’s individual group at the proper elevation at the distance engraved on that sight, be it 100mtrs, or 50 mtrs or what ever!

#3 Then there is the activity of working up a load that will shoot to the regulation already built into the rifle. Most to day call this regulating the rifle. This is OK, but causes another misleading idea about how a double really works.

This is the most complex activity encountered when a new to the owner double rifle is being loaded to shoot properly. Here, we need to start out very low so as not to damage the rifle, because the proper load is not known. This must be worked up very slowly, because the first shot fired may be the one that blows a very expensive set of barrels.

Simply because Webster gives only one definition for the word, means little to a specialized interment like a double rifle .

You physically regulate the rifle barrels by moving wedges between the barrels. You regulate the sights next, by cutting the sights so the point to the center of a composite group of both barrels at a pre-described distance, after the barrels are already regulated.

If I understand the question correctly then regulation is simply the act of soldering the barrels together to get the bullets to hit the same point of impact at X yards. It is done with wedges and solder and wire...If one wants to know where to stop the regulation process then he must shoot 4 or 5 groups with each barrel seperately, the gun can only shoot as well as the WORST barrel, so when you hammer the wedge and tie the wire and solder the barresl you stop at the worst barrel group.

The rest is sighting in the rifle and has nothing to do with regulation..

In this case the question is harder to understand than the process!

This begs the question ?
Is it easier to make a load up that will shoot to the same point of aim / regulation , by varying bullet weight, powder charge, powder type, primer. Or just pay the money and have the barrels moved. I think I will try the rloading route first.

Hey, after much coaching by "Big" Mac, I think I know that.

All ya gota do is try for a load like the one it would have been regulated for.

quote:

Originally posted by JAL:
Hey, after much coaching by "Big" Mac, I think I know that.

All ya gota do is try for a load like the one it would have been regulated for.

..............Right! Sounds simple doesn't it?

quote:

Originally posted by Grenadier:
I have often wondered why double rifles are regulated so the barrels cross at a set distance like 50, 75 or 100 yards. If the firing pins are 2-1/4" apart and the barrels cross at 75 yards then at 150 yards they are shooting a 2-1/4" of inches apart, at 225 yards they are shooting 4-1/2" apart, and 6-3/4" apart at 300 yards. Canting the gun can really throw the open the groups at the longer ranges.

It seems to me that it would make more sense to regulate them so that they shot as parallel as possible. For example, if the firing pins are 2-1/4" apart then regulate it to shoot the left barrel groups 2-1/4" left of the right barrel groups. That would shoot the same at 75, 150, and 300 yards. Parallel barrels would also mean that canting the gun would have less effect on group size.

There must be some technical reason for the crossing. I wonder what it is.

It certainly does make sense to regulate the barrels so they shoot parallel! That is the way they ARE regulated, in fact!

The barrels being regulated to cross at a given distance is a misconception shared by many other wise knowledgable gun writers,and people who have been around guns for their whole lives. It is a myth that the barrels a regulated to cross at any distance.

Where that idea comes from is two places. #1 is that the factory states that the are regulated "on target" at a given range. This has nothing to do with the regulation of the barrels convergance, but is the cutting (regulating) of the sights to be on point of aim at a given distance, just like any other rifle with fixed iron sights.

#2 is the fact that the barrels being each on the left, and right side of center of the rifle, causes the rifle to have a recoil arch that is opposite for each barrel. Each barrel recoils up, and away from the other barrel. The barrels are converging so that the barrel being fired will be pointing at a point that the sights were pointing at when the tigger was pulled, as the bullet exits the muzzle.

If the bullet is too fast, it will cross, if it is too slow it will shoot too wide. This is caused by a phnominon called "barrel time", and is the time the bullet remains in the barrel durring the barrels movement from recoil.

The sights are regulated after the barrels are regulated, to aim at a point that is half way between the centers of each barrel's individual group. The center of each barrel's group will always be on it's own side of the composit group of both barrels. The composit group of both barrels will be a slightly egg shaped (like an egg laying on it's side) group with the point of aim for the sights in center of that composit group, while the centers of each barrle's individual barrel group being on it's own side of the center of the composit group. The right side of the left barrel's group will overlap the point of aim, and the left side of the right barrel group will overlap the point of aim on that target at the distance the sights were regulated for, but the centers of the groups for each barrels will remain on it's own side of the center of the composit group of both barrels. In short, shooting parallel!

If you will look at the fine double rifles from the best makers in the world, who have multi-range flip-up sights, for down range distances, you will notice the center of these flip-ups all have a common center line. The only difference in these sights is elevation, with each flip-up being higher than the one before. If the barrels were regulated to cross at any range, these flip-ups wouldn't be in line, and wouldn't be worth the iron usd to make them. These things are expensive to make, and were not placed on the rifle for ornamentation. If the load is correct, the rifle will shoot to those sights at the ranges engraved on them. The only way this can work is if the center of each barrel's group remains parallel, down range! SO! it seems the makers took your advice before you were born!

quote:

If the bullet is too slow, it will cross, if it is too fast it will shoot too wide.

Mac I thought it was the other way around?

quote:

Originally posted by Palmer:

quote:

If the bullet is too slow, it will cross, if it is too fast it will shoot too wide.

Mac I thought it was the other way around?

You are absolutely correct, Allen! I went back and edited my post to reflect that correction! You know how it is when you get old, it seems the brain farts become epidemic!

Unfortunately Mac I do know how it is when I get old. Some days I don't know what I don't know.

Anyway thanks for the great explanation above.

quote:

Originally posted by Palmer:
Some days I don't know what I don't know.

.

I'm starting to think that is the case with me ALL the time, as I'm sure others do most of the time!

quote:

Originally posted by N E 450 No2:
There is my 75% Rule.

Once you have the proper powder charge for the full weight bullet, that regulates to the sights, you can substitute a bullet that is 75% the weight, use the same powder charge, and it should regulate and shoot to the sights.

This "Rule" has worked with 450/400, 450 No2, and several 470 double rifles.

With the 400's use a 300gr bullet.
With the 450 and 470's use 350gr bullets.

These 75% loads average @ 2330fps.

They give less recoil and a bullet more suited for smaller big game.

Thus my Browning O/U .30-06 which is regulated with 200 grain bullets should shoot 150's using the identical charge to my 200 grain loads?

This I must try.

308Sako

My 75% rule has worked with several doubles in the 450, 470 class and on several 450/400's.

Please give it a try as no one has tried it in a small bore double or an O/U as far as I know.

I am curious to see the results.

I hope to do this later this week. I shall post the results. Thanks for the idea.

quote:

Used to have a picture which I was told was too big... It's a nice rifle

What do we have here, a toy server? Just imagine the size of YouTube and PhotoBucket!

A fellow member and gentleman requested that since his (and possibly others)connection speed was not of this century could I please either resize the picture or delete it.

Since I was wishing to show it off, I thought that a link achieved both goals. Thanks for your concern.

Range visit scheduled for tomorrow AM, will post pictures of the results and action! Loaded in the same brass and with the same lot of powder and primers as the 200's. Choose 150 Nosler BT's as an accurate 75% bullet weight selection. The only difference is the seating depth is very different do to the shortness of the bullets by comparison.

Edit to add photo: