Foot Pounds

My 45 caliper target rifle just kicks my butt when shooting with a 500 grain bullet pushed by 70 grains of Swiss 2F powder. The shotgun I just made shoots 1 1/8 oz which equates to the same weight as the bullet and is not nearly as bad.. Is there a conversion chart of any kind that shows recoil of different rifling twists.

I ain't no rocket surgeon, but I'd say slower twist rifling produces less recoil. Cuzz the bullet is able to leave the chamber area more quickly. Making the recoil impulse diminish more quickly.

A really fast twist would prevent the bullet from leaving the chamber area quickly. Making the recoil impulse greater and longer lasting.

But I don't think fast twist or slow twist would produce any perceptible difference in feeling at the shoulder.

Shotguns, in my opinion, produce less felt recoil because the charge and shot are not as tightly constrained as a tight fitting bullet.

You're right, somewhat anyway, but to make that bullet twist there should be a scientific measurement out there somewhere.

cannonball1 said:

You're right, somewhat anyway, but to make that bullet twist there should be a scientific measurement out there somewhere.

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I'm sure there are bullet weight/twist rate calculations out there.

But I doubt very highly that felt recoil was ever figured into the equation.

Hitting a down range enemy was placed way ahead of someone's feels.

I don't believe rifle twist has any impact on the recoil. Twist rates are about best stabilizing a projectile of given weight and velocity.

Powder burns at a given rate. A .45 cal bore is a much smaller volume to fill than a 20 ga shotgun. In fact, it's about half for any given length. That's a faster rate of expansion, pushing harder on the projectile, and resulting in greater recoil.

Stock shape / design has a lot to do with perceived recoil.

64Springer said:

I ain't no rocket surgeon, but I'd say slower twist rifling produces less recoil. Cuzz the bullet is able to leave the chamber area more quickly. Making the recoil impulse diminish more quickly.

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Um, nope. Recoil is recoil as mentioned regardless of the twist rate, HOWEVER, there is a difference in actual recoil and ..., perceived recoil.

Shoot a 4 bore rifle, with a stock that fits you well, and you will notice the rifle has some kick, but surprisingly not too bad.... then shoot it again with the same load, but lift your head up off the stock and it will quite literally shake snot from your nose. Recoil was the same but how you and your body received it, and thus your perception of it, will be very negative.

Now with rifling, faster twisting will sometimes give the shooter disagreeable torque. In other words, the cheek side of the stock may move or may even slap the shooter's cheek, again making the perception of the recoil greater.

LD

Does your target rifle have a butt stock that is shaped like your shotgun or is it curved? Curved butt stocks should be mounted just above the bicep, this results in a difference in felt recoil.

Physics and friction tells me you are all wrong. Am I up in the night? Wouldn't be the first time. All I know is the 45 cal. percussion hammers me really bad compared to same load with my smoothbore.

And the percussion is 5 pounds heavier.

Guess you answered your own questions then.

Actually only 4 pounds heavier, but regardless, should make less recoil.

cannonball1 said:

Actually only 4 pounds heavier, but regardless, should make less recoil.

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My 460 S&W takes a 300 grain hard cast bullet. With a reduced powder charge it still pushes me into the next zip code when I pull the trigger.

Nature of the beast.

Where did you find a 500 grain projectile for a .45 caliber traditional muzzleloader?

That bullet has to be twice as long as it is wide. Doesn't matter what you do. You're going to feel that.

Twist adds to the recoil, but not significantly nor perceivably as it "restricts" the free movement of the projectile down the bore and causes a slightly higher pressure spike. It will not make near the difference to perceived recoil as a poorly fitted/designed stock.

I've never heard that rate of twist has an effect on felt recoil. In my experience barrel weight, stock design, powder charge and weight of bullet do.

If recoil is too severe it's likely the rifle is too light for the load you are using. I would also look at the amount of drop and cast off in the stock.

I have a couple LR rifles that give me a good deal of boot, and I use a PAST Mag Plus recoil pad when shooting them from the prone position: it works great.

Recoil is simple Newtonian physics. It’s entirely related to velocity and mass of tge projectile.
Should you get a 1500 foot pound load your projectile has 1500 ft pounds going out while 1500 foot pounds hits the breech plug. You absorb that across the butt, but also dissipated via the mass of the gun.
Recoil isn’t the problem, it how it’s absorbed. A pro boxer hits with more energy than a rifle bullet, but dissipates over the size of the fist.
Felt recoil is a function of stance, butt plate size, weight of the gun. Twist, shape of the projectile ect has zero effect. Only the mass and velocity of the ejecta.
A blank charge has little recoil because its mass of the ejecta is light and not moving very fast.
Heavy projectiles are producing more recoil because of the mass and the velocity.
Like wise Newton is watching your ball down range. A ball has little mass compared to air resistance it looses velocity and hence energy quickly. While a conical has more mass vs air resistance.

Check out the big brain on Brad.

cannonball1 said:

Physics and friction tells me you are all wrong. Am I up in the night? Wouldn't be the first time. All I know is the 45 cal. percussion hammers me really bad compared to same load with my smoothbore.

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Since you mention Physics, why leave out discussion of momentum and impulse? It’s not raw KE here but all of the above combined with stock design and how the shooter holds the rifle

Let me put it this way if you had a spring that barely fit a 30" barrel and you straightened that spring out it would, lets say approx, it would be three times the length. A rifled barreled bullet would go three times the smooth bore in that distance in that 30's" thus more recoil. And, centrifugal force requires more friction and energy. All I know a heavier gun should recoil less usually. Same grain of bullet and same grain of powder and the lighter smooth bore has less recoil. I would guess the smooth bore bullet would come out of the barrel faster everything else being the same, in other words more velocity.