doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Lengthen Forcing Cones - $75.00 per hole

Perceived recoil means: You can feel it but it can't be measured. Otherwise we're talking about measureable recoil. A gun with a recoil pad has less perceived recoil than one without a pad, but that has nothing to do with the recoil that can be measured--other than whatever reduction results from adding weight to the gun in the form of the pad. And even measureable recoil does not relate directly to pressure. Velocity and shot charge weight are the two major factors in measureable recoil, and lighter, slower loads can produce more pressure than faster, heavier loads. All you need to do to confirm that fact is to check reloading data.

IMO, holding down BOTH recoil and pressure is good for the gun; holding down recoil is good for the shooter.

Gentlemen, Gentlemen, Gentlemen;
I surely feel many have been carried away by smooth talking Advertisers. "If" you can measure the difference in recoil then you can feel it. "IF" you can't measure it then there has to be a significant difference in the way it is applied in order to "Feel" anything. Most of the differences we are speaking of here are "Extremely" Mi-Nute. Lets look at a few Facts. Assume a load of 1oz shot, a wad of 45 grains & a powder charge of 20 grains. Know what the weight of the shot, wad & half the powder ejected from the gun is - 1 1/8oz. I picked these weights for convenience. Now let's assume a MV of 1200 FPS from a 6 3/4lb gun having a 30" barrel. Guess what this gun weighs exactly 96 times the total ejecta weight. Now hold on to your hats, the gun starts to move the instance the load does in direct proportion to that of the load. Now I am going to introduce an intentional error by assuming the load travels the entire 30" which as we have the thickness of the base wad it will be a bit shy. However with that
96:1 ratio of load to gun while the load is moving 30" the gun will move 5/16" in "Free" recoil, not against a rigid shoulder. Even if the charge had a constant acceleration this would take place in .0035 Seconds. All the rest of the motion of the gun occurs from built up inertia or from the ejecting gases. The reason for that Half of the powder charge is that as the base of the wad reaches the muzzle the gases from the burning powder has filled the bore. Thus we could say that on average either that 20 grains weight have traveled 15" or that 10 grains weight have traveled the full 30".
As soon as the wad leaves the barrel the gases rush out at an increased velocity thus imparting a bit more recoil to the gun. Its always amazing that so many can "Feel" a bit of change in the burn rate claiming a slower burn gives them less recoil, but can't feel the results of an increase of both amount of gases being ejected or an increase in the rate of ejection. "IF" we change in some way to lower the Breech pressure while maintaining the same MV we will of course likewise raise the muzzle pressure, there Ain't No Free Lunch. Bottom line is the recoil of a shotgun is about 99.9% determined by weight & velocity of the charge against the weight of the gun Whether Measured or Felt.
Sure there are some factors which affect hot the recoil is felt, such as gun fit, how you hold it etc. The recoil pad works by spreading out the recoil of the gun. I would feel quite certain it does not fully compress in that under .003 sec's the charge is in the barrel but is continuing to compress as the gun continues in motion. A too Soft pad can in fact give you an increase of recoil just like holding the gun off the shoulder a bit & giving it a running start.
I can't feel a pea under 13 mattresses either or ever how many it was they out under the "Princess", sure glad I'm not so Dainty & Delicate as some seem to be.
Fact is if you use the same identical load from the same gun, But, you have done something to the gun which reduced its recoil (Assuming its not just in your head) then you have reduced the ballistics of that load. The Bird itself could care less whether you did this by saving a few pennies in powder cost or spent a bundle having the gun modified, but if you think you can reduce the recoil while maintaining everything else equal, you may be fooling yourself, but not Me.

What Miller has written is all good sensible stuff. The problem lies with 'perceived' recoil.
Some get bruised fingers, some bruised cheeks, some sore shoulders, some headaches.
Unfortunately, its really complicated, depending on gun fit, the individual concerned - all really hard to quantify.

My own view is fairly simple; If a gun is 96 times the load, recoil should be acceptable to the 'average' person if the gun fits OK and with a normal velocity cartridge.

Shooting more than 1/96 th of the guns weight is likely to cause unpleasant recoil to the 'average' person

I also believe that changing the forcing cones has an effect on recoil primarily by changing the muzzle velocity.

Yup, if it does change anything, which is doubtful. You don't really think that much gas gets by the plastic wad just because the forcing cone is ground out do you?

Whether one chooses to spend the money or not is purely a personal choice. In a blind test using two models of guns, a friend and I were able to discern which guns had the lengthened cones about 94% of the time; well beyond coincidence. I also got approximately 3 to 4% better patterns. Got the same from overboring, but the results were not addiditve; 4 to 5% max. All of these results were with heavy loads of #4 shot and larger, and plastic shotgups.
I have not overbored any SxSs, but I did have the forcing cones lengthened on two with no ill effects.

All this recoil chatter is all speculation, claims and disputes.

Probably not. But, in my case, it was nice to remove spent ammunition from the gun that didn't have the end ripped off. Spent plastic cartridges, with the ends ripped off, are somewhat un-appealing to me.

I have no idea if recoil changed, or velocity went up or down. But, patterns are much improved at the yardage I put the gun to use at, and instead of playing with a reloader, I just bought a bunch of English ammunition that fit the bill. Actually, I did that first, thinking it fit the bill, and discovered ripped ends on spent cartridges.

The gun doesn't do that anymore. I'm going to guess that is a good thing.


Best,
Ted

Sounds to me like you were shooting 2.75 inch hulls in 2.5 inch chambers....?.....Did this happen in those French guns you always talk about.....?

Old German guns have very sharp cones and will not tolerate over length hulls, as do some others.

If you shoot the correct length hulls for whatever chamber length you have with the original forcing cones, there should never be any ripped ends on the hulls, ever........(unless the hulls were worn out from reloading too many times in the first place).......

Is it possible you were using the wrong length hulls where the ends were opening into the forcing cones allowing the shot cups to rip the ends....?....This is a common classic occurance in some guns if you shoot hulls too long for the chambers......

In all my years of shooting thousands upon thousands of rounds all with original forcing cones and chokes in numerous original old shotguns, I've never ripped the ends off of any hulls, which would get anybody's attention fast...... But of course I shoot ammo that fits the chamber in the gun, which is probably important.

Anybody else around here experiencing "ripped off ends" from original cones with correct and proper length ammunition....?....

I already mentioned that the gun was built by Frank Tobin. It would seem you missed that part of the discussion.

Tobin is a pretty un-French name, as it were.

I also already mentioned that the gun didn't really have cones-they were more like steps. Stan Baker had never seen anything like it. He speculated that the gun was intended for a paper hull cartidge with a short roll or glued crimp of some sort, but, he really didn't know why. The gun was produced with the name "Tournament" on it, suggesting it was built for some other retailer. Maybe said retailer loaded different spec ammunition for use in the gun. It would have been produced around 1910 or so. Perhaps a client had his own ideas on what ammunition should be loaded for his guns, and requested the gun be built as it was. Who knows? It was, by all appearances, produced new with those steps. This gun, and the odd forcing steps, have been discussed at length several times here, over the years, and nobody really knew who it was produced for or why it had the odd steps, instead of a proper cone, in the barrels.

The only ammunition I've ever used in it is the afore mentioned Eley VIP 2 1/2 loading, with 5, 6 or English 7 size shot, prior and post modification. The ends were ripped on new ammunition prior to Stan Baker fixing the bores. I am unaware of a shorter load that could be used in a 16 gauge gun from the turn of the last century.

But, that doesn't mean there wasn't one. By the way, it really does throw remarkable patterns, now.

Best,
Ted

A shell should "Never Ever" be fired in a chamber having a step rather than a cone if its fired length is greater than the length of the chamber. Shells which upon opening lap into a "normal" cone (Neither ultra short/stepped/lengthened) by 1/8"-3/16" have been successfully used with out ripping the ends from the hull or any other undue consequence for nigh onto a century. Accept it or not, but this is indeed verifiable fact, & was occurring PBB (Prior to the Birth of Bell).
He may well have brought this to a lot of folks attention, but it was established "Fact" long before he ever thought about it.