muzzle velocity for recoil

Keegan said:
most of the time a lighter round for instance 115 grain on 9mm would have a higher veolocity than lets say a 147 grain but i have seen where that same round doesn't have a higher muzzle energy than a 147 grain. Isn't usuall the higher velocity would have the higher energy?
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Go back to your first post. Remember where you asked "If everything else is equal"? You can't compare a commercial 115-grain round against a commercial 147-grain round the way you're doing, because most likely everything else is NOT equal. Even if you can find both bullet weights from the same manufacturer and in the same "model" of cartridge -- you have no way of knowing if they both have the same powder charge (they probably don't), or even if they both use the same powder. Bullet weight isn't the only variable in loading ammunition.

Take another look at that article I linked to, from Shooting Times. It's for .45 ACP rather than 9mm, but the principles are the same. Look at Table 1. Three bullet weights, all loaded to 5.0 grains of powder, yield identical recoil energy. How is that possible? Simple -- for every action, there is an equal and opposite reaction. If the initiating action is the same in all three cases (i.e. the energy released by burning 5.0 grains of gunpowder), then the reaction must also be the same. However, they won't all feel the same to the shooter. And they won't all have the same muzzle velocity.

But, again, your original question was "if everything else is the same." That means the same gun, the same brass, the same bullet, the same primer, the same powder ... everything is the same except the velocity. But wait -- if everything is the same, how can we change the muzzle velocity? The ONLY way to do that with the same bullet and the same powder is to use less powder. Velocity = mass x acceleration. The barrel length is the same, the mass (bullet weight) is the same, so the only way for the same mass to be accelerated to a lower velocity in the same distance is to hit it with less energy. That means using less powder. Less powder ==> less energy ==> less recoil.

Later in that article (Table 3 and Figure 3) they compare the recoil from three different bullet weights all producing the same power factor. But now all things are not equal, because not only are the velocities different, Table 3 shows that it takes different powder charges to get the three different bullets to the same power factor. Surprise, surprise, the one producing the most recoil was the one using the most powder (action <==> reaction). But, although the amount of measured recoil (actually, barrel flip in a Ransom rest) varied, it didn't vary all that much. Note, by the way, that they didn't start the graph at zero -- the lowest number on the Y axis is 30. This distorts the visual representation of the data (which happens to be a pet peeve of mine). If you extend the bottom of the graph all the way to zero, in proportion, the variations across the top won't appear very significant. In fact, the variation from the 185-grain to the 230-grain is 7.8 percent. That's a difference, but it's not huge.
 
Aguila Blanca said:
Take another look at that article I linked to, from Shooting Times. It's for .45 ACP rather than 9mm, but the principles are the same. Look at Table 1. Three bullet weights, all loaded to 5.0 grains of powder, yield identical recoil energy. How is that possible? Simple -- for every action, there is an equal and opposite reaction. If the initiating action is the same in all three cases (i.e. the energy released by burning 5.0 grains of gunpowder), then the reaction must also be the same. However, they won't all feel the same to the shooter. And they won't all have the same muzzle velocity.
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Table 1 shows the theoretical model where different bullet weights pushed to the same power factor will produce the same recoil IF they used the same amount of powder. Data presented later shows that different bullet weights require different amounts of powder to produce the same power factor (Table 3). Heavier bullets require less powder.

5 grains of powder was arbitrarily used in Table 1 for the calculations, but the data is theoretical and not from live ammo.

If different bullets are loaded with the same amount of powder, heavier bullets go faster than light bullets and produce a much larger power factor. That data is shown in Table 2.
 
I'll tell you this: I've fired 500 gr. bullets loaded to around 1250 f.p.s. in the .45-70 out of a Thompson Contender, and a .44 Magnum load built around the 180 fr. JHP bullet at over 1700 f.p.s. fired from a Ruger Blackhawk.

The .45-70 load had a vicious recoil, the .44 Magnum not so much.

Another factor attributed to recoil is muzzle blast. Sharp recoil that produces an impressive fireball seems more severe than one with less muzzle blast.

My own observation is that, using all high performance loads, increasing bullet weight seems to increase recoil moreso than increasing velocity.

And, I've shot .30-40 Krag rifles that had a punch against the shoulder, but were fairly mild fired out of a handgun.

Further grips affect recoil. The rubber grips favored by many seem to geive the gun a running start before impacting my hand, and abrade the skin much more than smooth wood grips.

My observations.

Bob Wright
 
Aguila Blanca said:
Go back to your first post. Remember where you asked "If everything else is equal"? You can't compare a commercial 115-grain round against a commercial 147-grain round the way you're doing, because most likely everything else is NOT equal. Even if you can find both bullet weights from the same manufacturer and in the same "model" of cartridge -- you have no way of knowing if they both have the same powder charge (they probably don't), or even if they both use the same powder. Bullet weight isn't the only variable in loading ammunition.

Take another look at that article I linked to, from Shooting Times. It's for .45 ACP rather than 9mm, but the principles are the same. Look at Table 1. Three bullet weights, all loaded to 5.0 grains of powder, yield identical recoil energy. How is that possible? Simple -- for every action, there is an equal and opposite reaction. If the initiating action is the same in all three cases (i.e. the energy released by burning 5.0 grains of gunpowder), then the reaction must also be the same. However, they won't all feel the same to the shooter. And they won't all have the same muzzle velocity.

But, again, your original question was "if everything else is the same." That means the same gun, the same brass, the same bullet, the same primer, the same powder ... everything is the same except the velocity. But wait -- if everything is the same, how can we change the muzzle velocity? The ONLY way to do that with the same bullet and the same powder is to use less powder. Velocity = mass x acceleration. The barrel length is the same, the mass (bullet weight) is the same, so the only way for the same mass to be accelerated to a lower velocity in the same distance is to hit it with less energy. That means using less powder. Less powder ==> less energy ==> less recoil.

Later in that article (Table 3 and Figure 3) they compare the recoil from three different bullet weights all producing the same power factor. But now all things are not equal, because not only are the velocities different, Table 3 shows that it takes different powder charges to get the three different bullets to the same power factor. Surprise, surprise, the one producing the most recoil was the one using the most powder (action <==> reaction). But, although the amount of measured recoil (actually, barrel flip in a Ransom rest) varied, it didn't vary all that much. Note, by the way, that they didn't start the graph at zero -- the lowest number on the Y axis is 30. This distorts the visual representation of the data (which happens to be a pet peeve of mine). If you extend the bottom of the graph all the way to zero, in proportion, the variations across the top won't appear very significant. In fact, the variation from the 185-grain to the 230-grain is 7.8 percent. That's a difference, but it's not huge.
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Thank you for taking the time and breaking it down for me, that goes for everybody on here, i appreciate it.
 
Use this link to play around with some numbers.

http://www.handloads.com/calc/recoil.asp

If you don't have access to a loading manual use this site to find loads including expected velocity and powder charges.

http://www.hodgdonreloading.com/

The results are often surprising. Very often a lighter bullet, moving faster will burn more powder and recoil more than a heavier bullet moving slower. There are 4 factors to recoil and all have to be considered.

Weight of firearm
Weight of projectile
Weight of powder charge
Velocity of projectile

Plug in those numbers you'll get real numbers on ACTUAL recoil.

Of course how it feels is different and is impossible to accurately measure. Some handguns with a narrow grip concentrate the recoil into a smaller part of your hand and FEEL like they have more recoil than a handgun with a wider grip. Depending on barrel length and balance some guns have more or less muzzle flip. Plastic guns have some flex in the frame that spreads the recoil out over a longer period of time and makes it feel softer. A recoil pad on a long gun does the same thing.
 
Frank Etten's post on page one is useful. Many others have added useful things as well.

The formula's for standard mechanical recoil works very well on what they were designed for. But they do not translate directly to felt recoil. They can only give you a rough idea there. This is due mostly to the action of the slide dissipating the recoil impulse (the same is true for semiautomatic rifles). In a revolver that force generated as a recoil impulse is transferred directly to the hand of the shooter while in a semi it is not.

Compensators and porting also effect felt recoil by directing the hot gases upward which helps to keep muzzle flip lower.

Get a copy of the book "Understanding Firearm Ballistics" by Robert Rinker.

If we want to be simple the main thing is weight. Weight of the gun and weight of the bullet. If we want a bullet pf x weight to move at x velocity it is going to need x energy to do it. Increase or decrease the weight of the bullet and it's velocity and the energy need to do that also changes. More energy more recoil. A 200 gr. bullet at 1000 fps takes more energy to do that than a 115 gr. bullet at 1000 fps. So greater recoil for the heavier bullet.

tipoc
 
jmr40 said:
Use this link to play around with some numbers.

http://www.handloads.com/calc/recoil.asp

If you don't have access to a loading manual use this site to find loads including expected velocity and powder charges.

http://www.hodgdonreloading.com/

The results are often surprising. Very often a lighter bullet, moving faster will burn more powder and recoil more than a heavier bullet moving slower. There are 4 factors to recoil and all have to be considered.

Weight of firearm
Weight of projectile
Weight of powder charge
Velocity of projectile

Plug in those numbers you'll get real numbers on ACTUAL recoil.

Of course how it feels is different and is impossible to accurately measure. Some handguns with a narrow grip concentrate the recoil into a smaller part of your hand and FEEL like they have more recoil than a handgun with a wider grip. Depending on barrel length and balance some guns have more or less muzzle flip. Plastic guns have some flex in the frame that spreads the recoil out over a longer period of time and makes it feel softer. A recoil pad on a long gun does the same thing.
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thank you for that information, ill have to look up federal ammo powder charge because i don't see it on that website but great data in there.
 
I ask cause I personally struggle on trying to figure out which one has more recoil when I’m at the rainge.
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Assuming you mean while shooting at the range then what difference does it make. Shoot what you shoot best, and don't get hung up on all this recoil nonsense.
Seems like some sort of phenomenon with new shooters to be all worried about recoil.
 
You got it

That's the key, what we are speaking of here is felt recoil. Highly subjective.

9mm Makarov. I don't consider that a high recoil caliber, in my old CZ 83 it's a pussycat round.

The PA63? I'm good for a mag or two before I say enough, with ammo from the same box.
The PA63 is a single stack aluminum frame. It's esp. narrow and would be far more comfortable with grips that fill out the frame.

The CZ is not only heavier, it's a lot wider which spreads the recoil out.

Now my Contender with the original grip on it.....that one will get your attention. Need to put rubber grips on it. Hot .44 mag is painful.

I find the hand filling grip to be number one for me, with weight a close second with regard to FELT recoil.
 
With all this discussion, I am surprised that no one has mentioned that recoil is under the umbrella of Newton's 3rd law: For every action there is an equal and opposite reaction. Newton's 3rd led to the definition of momentum, which is mass times velocity. The mass of bullet plus powder times velocity of bullet plus powder equals the mass of the loaded gun times the backwards velocity of the gun. (I have forgotten how to figure the velocity of powder, but let's ignore that for now.) We also have conservation of momentum, which can be written as M1 x V1 = M2 x V2.

Your perceived recoil is greatly affected by the mass of the gun. Imagine you put your shoulder up to a rifle that weighed a million pounds, and fired a standard .308 rifle bullet. Your perceived recoil would be essentially zero. That is because when you put a huge mass into the M x V calculation, the rearward velocity of the gun would be essentially zero. On the other hand, a light weight gun means significant rearward velocity of the gun, which you would feel more, even if M x V is the same.

To some extent, the shape of the gun affects perceived recoil. The type of action can have an effect: some semi-autos reduce perceived recoil by causing a delay.
 
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thanks guys i understand on the muzzle velocity and muzzle energy, if everything else being equal, the higher the muzzle velocity and energy then the harder or snappier recoil.

ok now i have another question. Lets say not everything is equal for the exception of the pistol which lets say a kimber 1911 , 4 inch barell, 45...

Which round would make the gun recoil more ? Only way is to shoot them ? ive tried it and i don't think i can tell that much.

45 ACP - 230 gr HST JHP - Federal Premium Personal Defense
Muzzle Velocity - 890
Muzzle Energy 404

vs

45 ACP - 185 Grain JHP - Speer Gold Dot
Muzzle Velocity - 1050
Muzzle Energy - 453
 
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Compare M x V.

Energy is not a direct consideration in calculating recoil.

You can ignore the fact that weight and mass are different, because you want the ratio, so the weight to mass conversion factors cancel out
 
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keegan said:
Which round would make the gun recoil more ? Only way is to shoot them ? ive tried it and i don't think i can tell that much.

45 ACP - 230 gr HST JHP - Federal Premium Personal Defense
Muzzle Velocity - 890
Muzzle Energy 404

vs

45 ACP - 185 Grain JHP - Speer Gold Dot
Muzzle Velocity - 1050
Muzzle Energy - 453
Click to expand...

The recoil numbers will be similar, but the felt recoil will be different. Recoil from the heavier, 230-grain bullet will be more of a solid push/thump against the hand and arm. Recoil from the lighter 185-grain bullet will be a quicker, snappier impulse.
 
keegan said:
thanks guys i understand on the muzzle velocity and muzzle energy, if everything else being equal, the higher the muzzle velocity and energy then the harder or snappier recoil.

ok now i have another question. Lets say not everything is equal for the exception of the pistol which lets say a kimber 1911 , 4 inch barell, 45...

Which round would make the gun recoil more ? Only way is to shoot them ? ive tried it and i don't think i can tell that much.

45 ACP - 230 gr HST JHP - Federal Premium Personal Defense
Muzzle Velocity - 890
Muzzle Energy 404

vs

45 ACP - 185 Grain JHP - Speer Gold Dot
Muzzle Velocity - 1050
Muzzle Energy - 453
Click to expand...

Plug those numbers into the recoil calculators at the links previously posted and let us know what they say.
 
74A95 said:
Plug those numbers into the recoil calculators at the links previously posted and let us know what they say.
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i don't have the powder charge in either of those rounds so i wasn't able to input that section on both calculators. One calculator was asking for charge weight and the other one powder charge
 
keegan said:
i don't have the powder charge in either of those rounds so i wasn't able to input that section on both calculators. One calculator was asking for charge weight and the other one powder charge
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For this purpose, use 5 grains for the 230 grain bullet, and 6 grains for the 185 grain bullet. This is consistent with the article in Shooting Times, where the heavier bullet uses less powder than the lighter bullet.

You can always use data from a online loading manual, such as the Hodgdon manual, or from Western Powders, Alliant, and so on. Pick the same powder that is used for both weights to make it a fair comparison. You don't need to be especially picky about trying to match velocities. For most factory loads, they tend to use what would be near the maximum charge weight for a given powder.
 
74A95 said:
For this purpose, use 5 grains for the 230 grain bullet, and 6 grains for the 185 grain bullet. This is consistent with the article in Shooting Times, where the heavier bullet uses less powder than the lighter bullet.

You can always use data from a online loading manual, such as the Hodgdon manual, or from Western Powders, Alliant, and so on. Pick the same powder that is used for both weights to make it a fair comparison. You don't need to be especially picky about trying to match velocities. For most factory loads, they tend to use what would be near the maximum charge weight for a given powder.
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thank you. for manufacture and gunpowder, i used winchester 231, just didn't know which one to use from starting loads or maximum load so i just tried both grain powders and plugged them in.

Verdict is in.. haha - 185 with less recoil.
 
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