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Most folks understand "REGULATION" where double rifle are concerned, to mean a point where the barrels shoot to the exact same point of impact at only one range. This missconcepthion, is fostered by the fact that the barrels have to be built converging from chamber to muzzles. Without thinking very deeply, people take this to mean the the shots cross at some pre-concieved point down range. This seems correct,but when you place a barrel set from a double rifle in a vice, with the sights aligned on a target at the SO-called regulated range. Lets say, for this, the regulated range engraved on the rear sight is 100 yds. Now with the barrels placed in a vice, and set sights on target at 100 yds, take two empty brass and chamber them in the chambers of the barrels, with no primers in the brass. Now, look through the primer holes of each case, like looking through a peep sight. What you will see is, the RIGHT barrel will be pointing at a place on the target that is LOW, and on the LEFT of the target. Look thorugh the primer hole on the LEFT barrel, and you will see the LEFT BARREL will be pointing at a spot on the target that is LOW, and on the RIGHT of where the sights are pointing! WEARD, you say?

Well the reason for this is the fact that each barrel causes the rifle to recoil in an opposite way to the other barrel's way. Because of the way the rifle recoils being opposite, they must point in opposite dirrections to what seems realistic.

When the RIGHT barrel is fired, the rifle recoils UP, and to the RIGHT, and when the LEFT barrel is fired it recoils UP, and to the LEFT, and when the load is right, the POI on the target will be side by side with the center of each barrel's individule group being on it's own side of the POA of the sights, or paralell to each other, close enough together to form a composite group of both barrels, with the elevation on the same elevation as the point where the sights were pointing when the triggers were pulled.

The reason for this is a thing called barrel time . Barrel time is the amount of time the bullet is still in the barrel durring the recoil arch of the rifle! A double rifle absolutely must be allowed to recoil as if being fired off hand, or the rifle will not shoot properly. You can't rest a double rifle dirrectly on sand bags like poeple do with their bolt rifles. You can rest your foreHAND on the bags, but holding the rifle's forend as you would when shooting off hand. IOW, the double rifle must NOT touch anything but the shooter's hands, face, and shoulder, or it will not shoot properly.

The hand loading for a double rifle absolutely must start low, and work up very carefully. The flanged NE cartridges designed for double rifles are low pressure, and do not often show sign of OVER PRESSURE, till it is too late to save the rifle. When starting low, the bullets will hit the target HIGH, and on it's own side of the point of aim on the target for each barrel. This is because the barrel time is too long (SLOW) This is called SHOOTING WIDE and is always high. As the speed of the bullet increases, the bullets will get lower on the target, and move back toward the POA. So you increase the load,till the bullets impact the target just on it's own side of the POA, and at the elevation the sights are cut for, you then have a load that shoots to the regulation built into the rifle. More later!

Great detailed explanation, and thanks!

Something of an anomoly I've noticed over the years. When load developing for the 450/400's in particular...same weight bullet...3 inch guns were 408.3-1/4 were 411...and the original velocity supposed to be the same. Usually IMR 4831 sometimes a reloader powder...the 3 inch guns seemed to take a fair amount more powder to reach regulation or poa. The 3-1/4 guns almost always shot well right around 80 grains of 4831, the 3 inch ones needing more. Different barrel lengths would partialy explained it but often times they were equal too. I would have guessed that the shorter case due to slightly more pressures in the shorter case would have taken less. Never had pressur signs and the empties dropped right out. Just interesting to me.

Shooter93I think the 3" rifles were usually 60 grs Cordite loads,in a case that was almost the same in volume,but with a slightly smaller bore, so would have been regulated to that load, while a great number of the 3 1/4" rifles were regulated with 56 grs cordite, in the same volume case, only shaped differently, and with a larger bore size.

Besides each individual rifle being an entity unto it'sself some differences, in seemingly identicle rifles, are simply beyond comprehention, and do not follow the rules.

The 3 1/4" is supposed to generate 50 FPS more speed than the 3" version, but I find, with a crono, that they are just about the same, with regulating loads for each.

I have a lot of friends who have the 3 1/4" rifles, but I have never personally delt with the 3 1/4" rifles,other than helping them with theirs, on the range.

It has always been my contention, that many of the 3 1/4" rifles are re-proofed from black powder rifles. The 3" Jeffery was never offered in a black powder version, and is therefore automaticlly a Nitro proofed rifle, unless it it is a re-chambered 450/400 2 3/8" rifle. That however would be fairly easy to spot.

All the new 450/400 3" Jeffery chambered rifles are being made in the .410 dia, so they will shoot either the .410 Hornady or either of .408, or 411 bullets of other makers.

For sure every rifle is different...it was just something I found interesting...and both calibers were stamped for 60 gr load..not that is the end all. I'm also sure a lot of re=proofing happened. My 3-1/4 gun was made in 1913 and is stamped for the 60 grain load It appears unaltered and that's the only load it's marked as proofed for so maybe it was buit as a Cordite gun. The new Kynoch ammo is no good for this rifle either, lousy regulation and much hotter than I like to see...again..that's just my rifle. It's amazing hpw much reloading stuff is available now too. 35 years ago it could be a nightmare getting loads for doubl rifles...lol I loaded some 600 Nitros for fellow back then..they were old cases but had a 224 Weatherby case head fitted into the case to use boxer primers...anything to make them shoot I guess...lol.

Here is the More later:

Once you have found the proper load with either the soft point, or the solid, then you must find the proper load for the other bullet type! This has it's own rules as well!

If the soft point is the first one you loaded to shoot properly, then with a solid of the same weight, you must back off your working load for the soft, and work up slowy till the solid het the target at the same point as the soft point! There is a caution here: One must not use Monolithic solids in a double rifle, unless they are properly made. By this I mean, the only safe monolithic solids that is safe to use in all double rifles is one made of COPPER, and with pressure rings cut around the bareing surface. Like the GS CUSTOM, or the now, sadly, defunct NORTH FORK, FPS, and CPS bullets. The pressure rings are cut with their tops just the same diameter as the grouve diameter, and the bottom between the rings just shy of the BORE diameter! This gives the rifleing a surface to engrave, for the spin, but allows the metal displaced by the engraving, a place to go between the rings. This way the rifleing doesn't have to compress the whole solid body of the bullet.

The GS Custom


The North Fork


The reason for this is two fold. The barrels on the old rifles, is not as elastic as that of the modern barrels,and will somtimes have the rifleing swaged enough to show a raised rifleing on the outside of the barrel, because the steel in the old barrels doesn't return to it's origenal dimentions after the hard bullet passes through it. Lead core solids do not present this problem. The newer steels used in modern double rifles, is more elastic, and is less prone to this damage. However, there is another problem the sometimes occurs with the use of monolitic solids without the pressure rings. The barrels, being soldered to the ribs, and wedges between the barrels, will somtimes break the solder connection between the barrels, because the solder cannot react as quickly as the very elastic steel, and breaks loose! This is a very expensive damage to repair, and IMO, is not worth the risk of useing Monolithic solids in the barrels of a double rifle.

There are many good lead core solids both steel jacketed, and gilding metal that are far more safe to use in double rifles, and will do the job as well as any monolithic solid.

Great post on DR bullets...

Is anyone picking up the North Fork production? I hate to see tham vanish from the scene, as they were as good as they get...maybe better.

Unfortunetly no! Noone is picking up the line, as far as I know! I talked to Mike (NF maker) right after he stopped production, and he said there were no plans to turn it over to anyone else! Like you I certainly hate to see these bullets go away. I have 100 of the CPS, and 50 of the FPS bullets in .475 that I'm hording, for Cape Buffalo fodder in my 470NE. I may turn out a few on a lathe useing the ones I have as a pattern, for my own use, but like Mike, the commercial production requires seven days per week to make it profitable, that is why Mike quit! He's a lot younger than me, so I don't see myself getting into that. Too bad, because IMO, the North Fork CPS is the best Cape Buffalo bullet ever designed, and the FPS is most probably the best bullet made for Elephant hunting! However, we still have the GS Custom, but they are hard to come by, at times.

I know this is an old post, but thought I would post anyway. The monolithic solid made by Barnes should fill the bill.They are manufactured in calibers .375 on up.


http://www.barnesbullets.com/products/r ... ed-solids/

TakeEm

The standard mono-solids are poison for conventional double rifles or combination guns. They have very thin barrels that can and often are damaged by monolithic bullets without the rings like on the NorthForks.

New developments are showing up all the time that may solve this problem, however.