What has more recoil?

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kgpcr

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What has more recoil with all else being equal a fast burning powder in my 9mm and 115 grn bullets or a slower burning powder with 115 grn bullets?
 
Recoil is momentum is power factor. So, (115gn * powder charge weight * velocity), with the weight of the gun absorbing some recoil. So, all things equal, the slower powder will produce very slightly heavier recoil, very slightly spread out over time.
However, what you call recoil is perceived recoil and that depends on at least YOU, your grip, the gun, the gun's grip, the gun's weight and the recoil force.
Example:
Win M94 in .30-30 with steel butt plate--I can shoot about 20 rounds before my shoulder tells me to stop.
Ruger M77 in .30-06 with rubber bullet pad--I can shoot about 50 rounds and still be ready for more.
I can shoot 200gn bullets at 1000 fps (200 PF) in my 1911 all day. I feel my wrist twist and my arthritis scream with just one shot with 230gn bullets at ~890 fps (205 PF)—I have no idea why 230gn seems like the magic arthritis-irritating load. The recoil impulse of 250gn bullets in my 1911 at 750 fps (188 PF) doesn't bother me.
 
Simple question starting to turn into a theory and advanced reloading discussion. :p

When I was doing a lot of .44 Magnum shooting, 300 or so rounds a month, I could tell the difference between a load of Bullseye and a load of Unique, same bullet to approx. same velocity, and yes the faster powder will "feel" like more recoil...
 
Neither. A 115 will recoil with the same number of ft-lbs. regardless of how fast the powder burns. What's important is the weight of the pistol. A 1.5 pound pistol with the ammo have 1155 FPS will have 5.2 ft-lbs. of recoil energy. A 2 pound pistol with the same ammo with have 3.8 ft-lbs.
 
I seriously doubt there is enough difference in 9mm to notice. Most people never consider that the weight of the powder charge is a factor. This is an over simplification, but if you have a 115 gr bullet with a powder charge of 9gr you have about 124 gr of combined bullet and powder weight leaving the muzzle. If you can find a load that only needs 5 gr of powder to get the same speed then you only have a total of 119 gr leaving the muzzle. At the same speed the load that uses 9 gr of powder will technically have more recoil. But you'd have to be pretty sensitive to notice the difference.

According to my calculations a 115 gr bullet @1200 fps with 5 gr of powder would generate 3.9 ft lbs recoil from a 2 lb gun. If I were to use 9 gr of powder it'd generate 4.8 ft lbs. Less than 1 ft lb more recoil. But it is about 19% more recoil, so if you look at it that way I guess it can be significant. But most people can't feel 1 ft lb difference.

I don't think the speed of the powder is causing more recoil. It is the fact that you use more powder when using slow burning powder that generates more recoil.

With guns using a lot more powder the difference can be noticeable. I load mostly for rifles. I need 10-12 gr more powder in my 30-06 to get the same speeds as my 308 using the same bullet weights. Or as much as 15 gr more powder in 30-06 just to get 100 fps more speed. The 30-06 recoils more even with the same bullets at the same speeds and it is noticeable. It is really noticeable when you need 15 gr more powder combined with 100 fps additional speed.
 
Some of these responses are wrong.

It is a fact of physics that if more powder weight is required to push the same bullet to the same velocity than a powder that requires less weight, the powder that requires more weight produces more recoil. This is described at the link I provided in post #3 and is consistent with the conservation of mass.

Mathematical formulas that calculate recoil force require the weight of the gunpowder. See the link provided by dgod to see this for yourself. Use the same bullet weight and velocity and change only the powder weight and you'll see changes in recoil force.

The difference is real and can be measured and demonstrated empirically. See this link for an empirical demonstration: https://books.google.com/books?id=Y...ge&q=gunpowder and recoil brad miller&f=false

It's also demonstrated here: http://www.shootingtimes.com/ballistics/measure-relative-handgun-recoil/

And here: http://www.shootingtimes.com/ballistics/compensators-pressure-gas/
 
What has more recoil with all else being equal a fast burning powder in my 9mm and 115 grn bullets or a slower burning powder with 115 grn bullets?
In the interest of keeping things simple I liked the post #2 answer:
There are plenty of recoil calculators out there and while you can get different answers depending on which you choose. If you wish to bounce the numbers around on your own Hatcher's Notebook has a section on recoil energy and there is also the SAAMI White Paper FREE RECOIL ENERGY.

Finally as was mentioned there is the Free Recoil Energy expressed in Lb Ft and the Felt Recoil frequently expressed in units of Ouch, that sucker hurt (yeah, it's a technical term). So you can draw your own conclusions. :)

Ron
 
What confounds me, is that we are talking seven thousands of a pound in grain measurements. Will a slower powder really recoil that much more?
I am off to investigate the links provided, but I would think speed and mass of projectile, not ejecta, would have more of an impact upon recoil. Precieved or foot pound measured.

I am new and always learning so I will be pleasantly surprised regardless. I have always wondered about this aspect of handloading.
 
Some of these responses are wrong.

It is a fact of physics that if more powder weight is required to push the same bullet to the same velocity than a powder that requires less weight, the powder that requires more weight produces more recoil. This is described at the link I provided in post #3 and is consistent with the conservation of mass.

Mathematical formulas that calculate recoil force require the weight of the gunpowder. See the link provided by dgod to see this for yourself. Use the same bullet weight and velocity and change only the powder weight and you'll see changes in recoil force.

The difference is real and can be measured and demonstrated empirically. See this link for an empirical demonstration: https://books.google.com/books?id=YVOYCAAAQBAJ&pg=PA238&lpg=PA238&dq=gunpowder+and+recoil+brad+miller&source=bl&ots=PvySYyx7LT&sig=E7C1kkcfNFBEwSFMEgPJbbmk-48&hl=en&sa=X&ved=0ahUKEwiW4K-JrcbUAhVE1mMKHQhYBEMQ6AEIPDAC#v=onepage&q=gunpowder and recoil brad miller&f=false

It's also demonstrated here: http://www.shootingtimes.com/ballistics/measure-relative-handgun-recoil/

And here: http://www.shootingtimes.com/ballistics/compensators-pressure-gas/

For the original poster, this question gets asked frequently and all the formulas come out, then the bullet weights then to combinations of bullet and powder than the brands of powder, calculations done, etc etc. Then was it loaded on a Dillon?:)

There is actual real recoil and felt or perceived recoil. There is also the actual gun used. A heavy metal gun a polymer gun??

The whole equation of calculating the weight of the powder in the is mathematically correct BUT. Look at some load data.

How about Hodgdons, just because it is easy and laid out well.

Put in 9mm Luger , 115 gr bullet and put is say Titegroup and say Longshot. A fast and slow powder. Look at the velocity of both start and mam, compare the velocities, They are close enough for Govt work and within standard of high and low if you chronograph them. Now look at the powder charges used. Yes, the slow powder uses a tiny bit more around 1.00 grain max.

Now can anyone actually feel or perceive that 1.0 gr difference??????

http://www.hodgdonreloading.com/
 
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All this bandwidth when it's really easy to find out. Load up some 9mm rounds with W231 and HS-6 and shoot them. Mystery solved, no? (or whatever powder you have)
 
Because the charge weight of the faster powder is less there is less mass ejected so it has to have less recoil. (unless laws of Physics have been repealed)
Will say maybe 1 grain of powder make that much difference in the total recoil, no. It is more a recoil feel thing..
I find with the same velocity a load with say WSF sure feels to me like it has less recoil than a load with Titegoup or Bullseye at the same velocity.
To me the slower powder is more of a push, the faster powder is more of a snap. I can feel the difference, some prefer one over the other, only you can tell which you like best.

In rifle for example 7mm Rem mag 175gr bullet MAX charge US869 77gr 2758fps, Hybred 100V MAX charge 57.5gr 2740fps, the close to 20gr heavier charge would make a difference. IMO.
 
Even when a larger charge of a slower powder has more recoil, it can be smoother and more pleasant to shoot. Depends on how much difference in velocity. I had a 125 Gr N340 .357 Mag load (1300ish FP) that shot awesome, but had sharp recoil. My 158 Gr 2400 load (1200ish FPS) also shoots very well, but is more pleasant to shoot.

I don't know what the recoil figures are for those by the formula, but I know which one feels better.
 
It doesn’t make any difference what any formula or individual says, it’s all a matter of perception. The only way to find out what feels best to you in your gun is to load up some ammo and shoot it.
 
If you're loading max loads, generally the slower burning powder will push the bullet faster, and will accept a larger powder charge, so you'll have higher velocity AND greater powder weight.

@noylj was way off of of the mark, momentum = mass of the bullet * bullet velocity + mass of powder * propellant gas velocity. Results by different groups, including SAAMI, have shown, for handguns, the velocity of the propellant gas is 1.5 times that of the bullet velocity, so then the formula simplifies down to read:

momentum = bullet velocity * ( bullet mass + mass of powder * 1.5)

So if you load to the same velocity, the heavier powder charge will have SLIGHTLY more recoil. If you load to the same PRESSURE, more often, the slower powder will yield higher velocity, so you'll have more recoil both from heavier powder charge AND from higher bullet velocity.

If you load to the same velocity, you'll never be able to tell the difference from the powder charge difference, however. You're talking about 115grns at 1100fps, which is ~18 lbm ft/sec, whereas you're only talking about 6grn powder at 1650fps, which yields ~1.4 lbm ft/sec, so you only have less than 8% of the recoil contributed by the powder vs. the bullet. Swapping for a faster powder and only running 4.0grn, you'd be talking about 0.9 lbm ft/sec instead of 1.4... So 18.9 net instead of 19.4... Just not enough to feel yourself.
 
All this bandwidth when it's really easy to find out. Load up some... Mystery solved, no?

Would be nothing but crickets around here if everyone followed that advice.

I'm just waiting for Monday so we can start another "what press" thread...
 
From the thread above.

You could double up your fist and hit it as hard as you can. (Fast burn rate powder like W231)

Or you can push it with your open palm. (Medium burn rate powder)

Which one do you think will move the bowling ball faster & further without breaking all the bones in your fist??

But that would make you think, say using HS-7 (an old slow powder that works in 9mm) to push a 147 grain bullet to the same speed as VV N310 (one of the fastest powders for 9mm), that the HS-7 would have less perceived recoil than the much faster N310 and that is not the case. While HS-7 may have less peak pressure than the N310 load, pressure and perceived recoil are not synonymous.
 
"Because the charge weight of the faster powder is less there is less mass ejected so it has to have less recoil." What "ejects" the powder? Does the powder get ejected or has it burned and become a gas?
 
"Because the charge weight of the faster powder is less there is less mass ejected so it has to have less recoil." What "ejects" the powder? Does the powder get ejected or has it burned and become a gas?

"matter can neither be created nor destroyed"

From somewhere in the Universal Internet.:)

The first law of thermodynamics doesn't actually specify that matter can neither be created nor destroyed, but instead that the total amount of energy in a closed system cannot be created nor destroyed (though it can be changed from one form to another).

Run with this a dazzle folks!:)
 
The larger charge of slower powder will have more actual recoil, assuming the same bullet weight and velocity. In addition to its simple weight being added to the momentum, the larger volume of gas is essentially acting as rocket exhaust coming out of the muzzle, pushing the gun backwards.

This is also why in a gun with a compensator the larger charge of slower powder will generate less muzzle rise - that same "rocket" effect will be used by the comp to drive the muzzle down/flat.
 
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