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Forums10
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Sidelock
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Sidelock
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Stan Ol'Larry sure made you look dumb...
Just saying.
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Sidelock
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Sidelock
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Larry; I have made that statement in the past about hanging a gun on the wall if it was not considered safe with 8K loads, so I am likely the one you recall saying it. An exception to this would be a gun with light a breech section built prior to the introduction of smokeless. IF in a good sound condition I would consider shooting it with Black Powder Only. Also, I have stated on numerous occasions that the rise in pressure down the rest of the barrel is only a "Slight" increase. It is not normally enough to be concerned about. The fact remains though & is really beyond dispute, that using a load with a low chamber pressure when the same shot charge is given the same velocity, does Absolutely nothing to help the forward end of the barrel.
Now before someone flames me (Again) I am well aware that pressure is pressure & doesn't care if the color is Red, White & Blue or just plain Black. However, when it comes to propellants Black gunpowder is much more forgiving of any slight errors one may make in loading & it is virtually impossible to get an overload in a standard case for the gun.
Buzz; Max Peak pressure has nothing to do with recoil. The formula for recoil is ejecta weight which is shot weight plus wad weight plus 1¼-½ time powder weight. That 1¼ to 1½ will vary whether one is loading a light shot charge with a fast powder or a heavier charge with a slow powder. This is predominately an estimate & is to offset the increase in the velocity of the Gases as they exit the muzzle, which adds to the recoil. As an example, let's take a 3-1 1/8 load using a wad which weighs 35 grains & 20 grains of powder. We'll use a middle of the road for the powder multiplier & take it at 1 3/8. We now have a total ejecta weight of 555 grains which converted to pounds gives, to keep figures even, 0.080 lbs. Multiply this by 1200 fps & you get 96. Divide that by the weight of the gun. Let's use 6 lbs even & you get a recoil velocity of 16 fps for the gun. I find the recoil velocity to me much more useful than Recoil Energy personally. A recoil velocity of around 15 fps is mild, 16 is getting a bit stiff & if I'm going to shoot more than one or two shots I do not want to exceed 16 by much.
So, Yes, you are correct, both the velocity of the shot & the recoil of the gun are generated by pressure. Neither, however, are directly proportional to the Max Chamber pressure. This is what has confused many. That old Bug-a-Boo of thinking the max pressure is the end all of shotgun ballistics. The Max pressure is truly of importance only to ensure the load does not exceed the pressure the chamber was designed to handle. In reality, it plays a very minor role in other aspects, including velocity, recoil, the strain on the action & splitting of stocks. Ejecta weight & velocity are the important factors in all of those. Pressure is not in the formulas for figuring any of them.
Last edited by 2-piper; 06/20/19 10:30 PM.
Miller/TN I Didn't Say Everything I Said, Yogi Berra
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Sidelock
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Sidelock
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Joe; I realized that, but thanks for stating it.
Miller/TN I Didn't Say Everything I Said, Yogi Berra
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Sidelock
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Sidelock
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I have read of many people commenting on Longshot powder's nasty recoil. It is a punch, not a push, and yes I was using it to duplicate other heavy loads only to see how the patterns turned out on the patterning board. Funny how a powder change can affect that. I would suspect skeet shooters have definite preferences concerning "soft" shooting powders, as well. Nothing likes hundreds of rounds to make you want to find a little more comfort.
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Sidelock
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OP
Sidelock
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Miller; Thank you for taking the time and effort to explain this complex concept of recoil and the relation to pressure to us/me. I appreciate it/you. So, am I correct to say, recoil has no or very little relationship to MAX pressure but is more related to total pressure which is defined by that area under the pressure curve?
Socialism is almost the worst.
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Sidelock
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Sidelock
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I appreciate it, too, Miller.
My current bismuth load for ducks, using my HE Fox, uses Longshot powder. I haven't noticed any unusual recoil characteristics with it, compared to the IMR 7625 I was using before. In a lighter gun I might notice something different, but I doubt it. I have noticed the differences, in loads of roughly the same shot weight and velocity, as far as "pushing" and "punching". I've never heard it put exactly like that, but it's a good way to describe the sensation.
SRH
May God bless America and those who defend her.
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Sidelock
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Sidelock
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Larry will be along shortly to set you straight...
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Sidelock
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Sidelock
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Miller; Thank you for taking the time and effort to explain this complex concept of recoil and the relation to pressure to us/me. I appreciate it/you. So, am I correct to say, recoil has no or very little relationship to MAX pressure but is more related to total pressure which is defined by that area under the pressure curve? That's it Buzz. The velocity is as you said the result of the Force applied to the load & of course as you also said that Force is generated by pressure. Also, some facts worthy of consideration is the total time from ignition to the load exiting the muzzle is around .003 of a second will vary just a wee bit according to load). Total movement of the gun during that .003 second is proportional to the weight of the load & the weight of the gun. In the example, I cited above where the total load weight was 0.08 of a pound & fired from a 6-pound gun the gun movement at the time of exit would be about 5/16 inch. The rest of the movement is the result of the Inertia given it in that brief period. It is also well to keep in mind that Fast vs Slow is all relative. The entire range of powders suitable for shotguns is a rather small range. They are all extremely Fast if you compare them to burning an old worn out cotton batting mattress. They are all Extremely Slow if you compare them to the Detonation of a high explosive.
Miller/TN I Didn't Say Everything I Said, Yogi Berra
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Sidelock
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Sidelock
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He'll reply tomorrow morning about 7 to 7:30, Miller. He ain't done yet, I'll bet'cha.
SRH Well Stan . . . speaking of being done . . . I'm still waiting to hear about a shotgun that was sleeved using Whitworth tubes. Or maybe you're done on that one. And then there's your contention about big shoots and how there will always be more top level shooters than average shooters. Results of this year's Wisconsin Ironman, with 290 shooters: Total of 91 in Master, AA, and A Classes combined. Outnumbered by the 96 shooters in Hunter Class. Funny you would bring up two past discussions where you clearly lost the debate both times. One more time, that ain't a big shoot. Spread your wings Lar'. Get out a little more. It'll do your perspective good. Larry Brown ............... not necessarily right, but never in doubt. SRH That's funny, Stan. The Ironman really exists, happens every year, draws around 300 shooters. Our whole state has fewer than 6 million people; GA isn't far from 10 million. And the Ironman takes place up north, the least populated part of the state--not down by Madison and Milwaukee. Pretty darned big deal for our state. Meanwhile . . . not sure how I lost on a gun sleeved with Whitworth tubes. Does one of those even exist? I'll believe it when I see one. But then, you never know. One of those UFO's the military is observing might land someday and a little green guy that looks like E.T. might step out. Or maybe looking like Chewbacca. Or Princess Leia, if we're lucky. But I'm not buying that either until I see it.
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