What produces recoil? Velocity or payload?

John Singer said:
How is that true when

KE = 1/2 x M x V^2

The kinetic energy that causes recoil varies directly with the mass and with the square of the velocity.
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True, but there's quite a little bit involved with determining velocity of the gun. If you look above at the "simplified" formula I provided, the shot weight ends up getting squared too. It's not exactly a direct relationship (x% of one is worth x% of the other), but it's close. A % change in muzzle velocity does have slightly more effect on recoil energy than the same % change in shot weight, but it's almost insignificant. Here's a link for the weirdos like me, who love math.

(Note: in the formula I gave above, I used KEO's variable names for consistency. Not SAAMI's variable names. Same effect though.)
 

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A5 Sweet 16 said:
I'm very certain that the intent of most manufacturers is to give you the weight written on the box in shot only. Maybe there are some anomalies that don't, but an anomaly isn't the norm.
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Same here. I've cut open and weighed quite a few shot charges. Off the top of my head- Remington, Federal, Winchester, Kent, B & P, Fiocchi, and Hevi. 12, 16, 20, and 28 ga.
With the exception of Hevi, the shot charges have all been right on, or just a hair above or below.
With Hevi, you can be certain it'll be well below. The Hevi-bismuth 28ga 6's are supposed to be 7/8 oz. I checked 3 shells and they were all just a tiny bit above 3/4 oz. They do kill birds though, I've shot a bunch of sharpies and huns with them. Similar experience when I checked some 16ga Hevi-bismuth.
 
A5 Sweet 16 said:
That's your backup? A picture of stuff that weighs 1.5 ounces? With exception of Hevi, most, if not all, shot charges I've weighed have matched the claim on the box. All reloading & black powder data refers to shot weight only. Not shot plus wad, spacers, etc. I have no proof you're wrong, but I'm not buying what you're selling. I guess I'll have to cut open a bunch of shells & satisfy my curiosity.
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Waiting on emails from federal, win, and rem to see what they say.

This just the email regarding my pictures above.
 

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Here are a few of my payload weights from factory shells.

Average pellet counts and payload weights from 5 shells

12 GA 2 ¾" FEDERAL FIELD & TARGET LOAD
1 1/8 oz #7 ½ lead (486 pellets) @ 1200 fps
PELLETS/SHELL (1 1/8 ounce = 492.2 gr)
In-shell pellet count / weight (grains)
Aver. 486.4 / 512.98 gr

12 GA 2 ¾" FEDERAL TOP GUN LOAD
1 1/8 oz #7 ½ lead (405 pellets) @ 1200 fps
PELLETS/SHELL (1 1/8 ounce = 492.2 gr)
In-shell pellet count / weight (grains)
Aver. 405.4 / 488.44 gr

12 GA 2 ¾" WINCHESTER UNIVERSAL LOAD
1 1/8 oz #7 ½ lead (356 pellets) @ 1200 fps
PELLETS/SHELL (1 1/8 ounce = 492.2 gr)
In-shell pellet count / weight (grains)
Aver. 356.2 / 470.9 gr

12 GA 2 ¾" WINCHESTER SUPER-TARGET LOAD
1 1/8 oz #7 ½ lead (368 pellets) @ 1200 fps
PELLETS/SHELL (1 1/8 ounce = 492.2 gr)
In-shell pellet count / weight (grains)
Aver. 368.2 / 468.46 gr

Gun Club “Hard Gun Club Shot”, #7 ½ (375 pellets / 485.5 gr.)

Premier STS “High Antimony Hard Lead Shot”, #7 ½ (408 pellets / 492.2 gr.)

Premier Nitro 27 “High Antimony STS Magnum Shot”, #7 ½ (420 pellets/ 503.1 gr.)

12 GA 2 3/4" Boss Unmuzzled Bismuth load
1 1/4 oz #4 Bi (192 pellets) @ 1350 fps
PELLET COUNT / WEIGHT (grains) (1 ¼ ounce = 546.9 gr)
Aver. 191.8 pellets / 549.08 gr

12 GA 3" Boss Unmuzzled Bismuth load
1 3/8 oz #5 Bi (267 pellets) @ 1350 fps
PELLET COUNT / WEIGHT (grains) (1 3/8 ounce = 601.56 gr)
Aver. 266.6 / 606.92 gr

12 GA 3" Boss Unmuzzled Bismuth duplex load
1 1/2 oz #3 Bi (123 pellets) + #5 Bi (103 pellets) = 226 total pellets @ 1350 fps
PELLET COUNT / WEIGHT (grains) (1 1/2 ounce = 656.3 gr)
Aver. 226.4 / 651.8 gr
(#3 Bi/123.2 + #5 Bi/103.2 = 226.4 pellets)

12 GA 2 3/4" Kent Upland Bismuth load
1 1/4 oz #5 Bi (197 pellets) @ 1350 fps
PELLET COUNT / WEIGHT (grains) (1 ¼ ounce = 546.9 gr)
Aver. 197.0 / 518.06 gr

12 GA 2 3/4" Kent Waterfowl Bismuth load
1 1/4 oz #4 Bi (212 pellets) @ 1350 fps
PELLET COUNT / WEIGHT (grains) (1 ¼ ounce = 546.9 gr)
Aver. 212.4 / 514.0 gr

12 GA 2 ¾" HEVI-Bismuth load
1 ¼ oz #5 Bi (228 pellets) @ 1400 fps
PELLET COUNT / WEIGHT (grains) (1 ¼ ounce = 546.9 gr)
Aver. 228.4 / 485.42 gr + flax seeds 12.68 gr

12 GA 3" Hevi-Hammer Upland Duplex (bismuth/steel) load
1 3/8 oz #3 Bi (55 pellets) + #3 Steel (126 pellets) = 181 total pellets @ 1350 fps
PELLET COUNT / WEIGHT (grains) (1 3/8 ounce = 601.6 gr)
Aver. 180.8 / 557.42 gr + flax seeds 16.38gr
(Bi/55.4 + Steel/125.6 = 181 pellets) (Bi/30.6% of payload)
 
Sporting Arms and Manufacturers Institute (SAAMI) has voluntary industry standards published in the American National Standards which include:

1) Pellet size variations allow for +/- one pellet size (+/- .010" dia.) of variation in “game” loads and +/- ½ pellet size (+/- .005" dia.) of variation in “target” loads,

2) Load weight variations can range from +4% to -7% in game loads and +3% to -5% in target loads,

3) Pellet counts per ounce can vary by +/- 10% for both game and target loads, and

4) Load velocity can vary by +/- 90 fps for both game and target loads.
 
I may regret this...

I've been shooting shotguns for over 50 years and I'm struggling to understand why this is a discussion, but here is my take --

1. 12-gauge kicks (scientific term?) more than 16, 20 or 410.
2. High brass shells kick - that term again - more than low brass shells
3. Never really worried amount pellet count, maybe that explains my misses. Figured big time ammo manufacturers knew more than me.
4. If I'm shooting at a wild pheasant on the rise, recoil had better not be bouncing around my brain calculator doing lead calculations, when to pull the trigger.
However, if I was designing, manufacturing and selling ammunition, this would be relevant.

Hope I forget about this discussion before November arrives again.

Be safe out there!
 
Recoil doesn't "bother" me when hunting, as in it's not painful. I remember turkey hunting with an inertia gun and having to twist around a bit because of course the turkey came in from a direction I had not anticipated. I was in a weird crouch position and had to let a few rounds go before I got him. I remember the butt of the gun bouncing around on my shoulder a good bit.

I was pheasant hunting this year and had dropped a federal prairie squall shell in my O/U bottom tube. When I touched it off it definitely caused the muzzle to jump and the buttstock too. This isn't going to be a net positive on the second shot. I normally only shoot the pterodactyl loads from a gas gun.

When shooting clays I always look for the lighter/slower loads. Shooting high volume teeth rattling shells isn't fun, and is a good way to develop a flinch.
 
KEOutdoors said:
Waiting on emails from federal, win, and rem to see what they say.
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I'm really super amazed. I emailed Winchester, Federal & Remington. All 3 responded within a couple hours (that's the amazing part) & said the payload weight on the box is for SHOT ONLY. Suffice to say that's industry standard.

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Recoil is felt when target shooting and not felt when shooting game......

In my experience i have only notice the hotter, high velocity, shells producing noticeable recoil when shotting at birds.
 
I think someone earlier in this thread was just "shooting from the hip." But at least I know Hornady includes the weight of the wad in the payload. As they only produce buckshot and slugs in the shotgun dept. this info comes in really handy for bird hunting.
 
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