12ga vs. 20ga recoil--why the difference?

I'm curious why a 20ga is reported to have lower recoil than a 12ga. In some of the forums, it seems that even a 20 and 12 of the same model place the 20ga having up to 40% less recoil.

This has always seemed strange to me--I thought the recoil was just the result of an "equal and opposite reaction". If I'm firing say, a 1ounce load of shot, out to lets say 1100fps, they should really produce exactly the same recoil (probably more for the 20ga, because it would probably be lighter).

Can anyone clear that debate up? It just doesn't make a lot of intuitive sense why there should be a difference--same weight projectile fired at the same velocity, should produce the same recoil (all other things equal--weight of the weapon...)

I'm afraid that I'm not a deeply scientific person, and maybe you need one to answer this question. First, though, have you ever actually fired both a 12 Ga. and a 20 Ga. from the same model shotgun--let's say a Remington 870? There is a marked difference. There was something in Physics class about an action getting an equal reaction, and the 12 Ga. is larger, containing more powder, larger wad--and even if the shot load is the same, like 1 oz., there's more going out the front and recoiling to the rear. Anyway, that's what my shoulder tells me......

DG

I've an H&R Topper in 20 gauge full choke that will flat light you up with #6 shot high brass.

Plastic butt plate and *might* weigh 6lbs.

My wag is that the reason for less recoil in 20 gauge is that there is usually less powder, and maybe slower burning powder at that.

It is kind of difficult to directly compare 12 and 20 guage guns, because the 20 often has a smaller frame even though the model name may be exactly the same. Unless we are talking the cheaper single shots of yesterday.

Robert

A 12 ga certainly recoils more than a 20 ga. The biggest reason is that a 20ga target load is 7/8 oz of shot while a 12ga is 1 1/8oz. That’s 28% more shot in the 12ga. The velocity of both is about the same so more powder is needed in the 12ga. A typical powder weight in 20ga is 14gr. 12ga is about 20. That’s about 40% more powder.

The combination of more shot and more powder gives more recoil. The max 20ga load is about 1 3/8oz while the max 12ga load is close to 2oz of shot. Quite a difference. 2oz 12ga turkey loads are not fun to shoot! There is a huge difference when shooting slugs also.

If both shotguns were the same weight and used the same shot charge weight at the same velocity, the recoil would be the same.

nope..given same payload same gun weight and same velocity the 20ga will recoil MORE....TIGHTER BARREL =more pressure..wont be much in it.
but reason 20ga often said to be lesser recoil is the lesser payload
biggest mistake MANY Dads have made is buying a light single barrel 20ga for jnr to shoot then feeding it 3" magnum shells throwing a 12ga payload of over an ounce.... same gun with less than oz in 2 3/4' shell at moderate velocity is a whole different ballgame.
its the reason I laugh when folks say a 28ga is better than .410 when both chuck 3/4oz at same velocity.... the end result is the same on both ends.... 28ga could have slightly less recoil for reason given above and COULD pattern better as less stress on shot through slightly bigger hole on barrel..but nothing in it in either case if you do homework on pattern board.


lol said same as above poster before reading his post...doah.

I think that was my question--I realize 20ga loads can really be light (I have some reloading data for 5/8 ounce loads--not tried them, but I assume they are very light on the shoulder). But I was talking specifically about firing the same projectile weight to the same velocity. An ounce at 1100fps is an ounce at 1100fps, regardless of the diameter of the projectile.

I haven't taken my break actions out (I have a 20 and 12 that are similar--imports with toy-like black plastic stocks) to test and see what difference is. I think I'm wondering if they ACTUALLY have noticably different recoil. Or if I got the 20ga because I read it was lighter recoil, and because I believe it has lighter recoil, I actually perceive less.

Recoil is not caused by pressure...that is a common misconception.

These are the factors that affect recoil:
Weight of shot and wad...mostly shot as wads are very light anyway.
Velocity of the load...higher velocity will increase velocity
Amount of powder....more powder adds to ejecta (like the shot and wad beign ejected)...but it is a minor contributor
And lastly weight of the gun.

There will be no discernable difference in a 1 oz load at 1200 fps out of a 12 ga or 20 ga gun of the same weight.

If you want to play around with numbers:

https://gunpros.com/recoil-calculator-charts/

Quote:

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Originally Posted by dverna

Recoil is not caused by pressure...that is a common misconception.

These are the factors that affect recoil:
Weight of shot and wad...mostly shot as wads are very light anyway.
Velocity of the load...higher velocity will increase velocity
Amount of powder....more powder adds to ejecta (like the shot and wad beign ejected)...but it is a minor contributor
And lastly weight of the gun.

There will be no discernable difference in a 1 oz load at 1200 fps out of a 12 ga or 20 ga gun of the same weight.

If you want to play around with numbers:

https://gunpros.com/recoil-calculator-charts/

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Try shooting a 3/4oz load from my 3lb 7 oz 410 and you will realize the weight of the gun has a lot to do with recoil.

I have successful loads for my 12 gauge using 1, 7/8, & 3/4 oz loads. I currently shoot 7/8 oz loads using 15 grains of powder and I haven’t had any need to complain about recoil. The 3/4 oz loads get pushed a little faster but I don’t see an issue with recoil there too.

It's the weight. A 12 gauge weighs more than a 20 gauge. For every pound you take off about 25% of recoil. I still think a 20 kicks but not as bad as a 16 gauge. Lighter and faster gun shooting a smaller charge = the same recoil as a heaver gun shooting a stouter charge. Shoot a 7/8 oz load at 1500 fps out of a 20 and a 1 1/8 oz load at the same speed out of a 12 and both sting. Reduce it down to 1200 fps and you will see both are manageable. Shoot a 1oz shot load at 1200 fps out of a 12 and its like a kitten.

Quote:

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Originally Posted by dverna

Recoil is not caused by pressure...that is a common misconception.

These are the factors that affect recoil:
Weight of shot and wad...mostly shot as wads are very light anyway.
Velocity of the load...higher velocity will increase velocity
Amount of powder....more powder adds to ejecta (like the shot and wad beign ejected)...but it is a minor contributor
And lastly weight of the gun.

There will be no discernable difference in a 1 oz load at 1200 fps out of a 12 ga or 20 ga gun of the same weight.

If you want to play around with numbers:

https://gunpros.com/recoil-calculator-charts/

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Physics says this is the correct answer.

Besk, the enlarged section covers your statement.

dverna has it right, gun weight can be a consideration and MOST 20 ga shotshells are loaded with less shot than MOST 12 ga. A light twenty can actually kick harder than a heavy twelve depending on shell selection.

Lighter gun kicks harder, heavier load kicks harder, gauge is less important than the weight of the gun and the power of the load.
Tim

Quote:

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Originally Posted by besk

Try shooting a 3/4oz load from my 3lb 7 oz 410 and you will realize the weight of the gun has a lot to do with recoil.

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thats what I was getting at about Dads buying a light 20ga for jnr and feeding it magnum shells...

I shoot 7/8 oz. out of both a 12 and 20 gage semi-auto. Would be hard pressed to find a difference in their recoil.

think the shape of the stock also effects recoil

The answer is a bona fide maybe. Or as they say, you are certainly entitled to your own opinion, you are NOT entitled to your own facts.

Recoil certainly is a product of what is going out vs. what is getting shovedback. Alter one or both one way or another, you will alter recoil. So, it is entirely possible for a 12 gauge to kick more than a 20 gauge. But things can be altered so the opposite is true. Shoot a 3/4 oz light target load at 1050 fps out of an 8 lb. 12 gauge. Shoot a full 1 oz field load at 1290 fps out of a 6 lb 20 gauge, and then talk to me about the respective recoil!

Shotgun gauges weren't created to differentiate recoil. Each was designed for the particular game to be hunted and the terrain and distance to be engaged. If comfort is the goal.....Well, what can anybody say.

The shape of the stock will not affect the recoil, but it can greatly affect the PERCIEVED recoil. A badly shaped stock will affect the muzzle rise and can cause the comb to hit the cheek harder so that the same amount of recoil will feel greater. Also, the resistance provided provided by the shooter's weight and stance can affect the perceived recoil.

I have one of the Yldis folding 410s that Academy sold about a dozen years ago fo a little over a c-note. It is an absolute whisp of a thing at 3.3pounds. Its perceived recoil is much higher than my 12 gauge 870. Even though it is just a little .410. I also have a 20 gauge youth model 870, with stock spacers to bring it to my preferred l.o.p., and although it it lighter than my 12 gauges, the ammo I use in it makes it seem like a light kicker in comparison. Weight of gun, weight of payload, speed of payload.

Come on guys,,, Did none of you pay attention in school?

Newtons Law says "for every action there is an equal and opposite reaction."

The 20 ga. has a lighter payload than a 12 ga. all else being equal, the 12 ga. has to recoil more. Simple as that.

Any other conclusion is strictly Subjective and not based on Empirical Fact.

This ain't that hard?

Randy

Here is a good tool for figuring shotgun recoil http://www.omahamarian.org/trap/shotshellenergy.html

Payload, velocity and gun weight are the major factors in recoil. Gun fit, especially drop at heel and cheek rest height do greatly affect perceived recoil.

Hey Randy, I routinely load 3/4 oz in the 12 gauge ( as well as 16, 20, and 28 gauge.) Just because it's a 12 don't assume payload is heavier.

So your "facts" are not as empirical as you think.

Burn rate of the powder also affects felt recoil. The powder mass also has to be calculated into actual and felt recoil.