recoil, real or inferred!!!

Doc Holliday 1950 said:
..."Does muzzle Velocity and Muzzle Energy relate to felt recoil or kick?
Rather the lower the MV and ME the less felt recoil....
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As long as you are taking about felt recall, it's not necessarily directly related to those measurable, physical quantities. Felt recoil can be very subjective, and factors such as the shape of the grip and the distance the axis of the bore is above the grip, and the burn rate of the propellant can affect how recoil is perceived.

On the other hand, recoil energy is a precise, physical quantity that is a function of the weight (mass) of the bullet, the weight (mass) of the powder charge, the muzzle velocity of the bullet, the muzzle velocity of the powder gases, and the weight (mass) of the gun. If you have those quantities for a given load in a given gun, you can calculate the amount of recoil energy produced when that load is fired in that gun. Note that --

  • Recoil energy is directly proportional to the mass of the ejecta, i. e., recoil energy increases as the mass of the ejecta increase. The mass of the ejecta is made up of --

    • The mass of the bullet; and

    • The mass of the gases produced by the burning powder (which is directly proportional to the mass of the powder charge).

  • Recoil energy is directly proportional to the velocity of the ejecta, i. e., recoil energy increases as the mass of the ejecta increase. The velocity of the ejecta includes --

    • The velocity of the bullet; and

    • The velocity of the burning powder gases.

  • Recoil energy is inversely proportional to the mass of the gun, i. e., as the mass of the gun increases, recoil energy decreases.

If you're interested, you can calculate the recoil energy of a given load using the following formula1:

WG = Weight of gun in pounds
WB = Weight of bullet in grains
WP = Weight of powder charge in grains
VB = Muzzle velocity of bullet in f/s
I = Interim number (Recoil Impulse in lb/sec)
VG = Recoil velocity of gun (f/s)
EG = Recoil energy of gun (ft lb)

I = [(WB * VB) + (WP * 4000)] / 225218

VG = 32.2 * (I / WG)

EG = (WG * VG * VG) / 64.4

Felt recoil is a subjective matter. It's how you experience the recoil, and it's really something that only you can decide for yourself.

In general, for example, a lighter, fast bullet may produce recoil energy comparable to that of a heavier, slower bullet. But the recoil energy of the load with the lighter bullet will be manifest in a shorter pulse (distributed over a shorter period of time), while that with the heavier bullet will be distributed over a longer period of time. Depending on how you, personally experience these two types of recoil pulses, one may seem greater to you than the other, even though they really have similar recoil energy.
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1. This formula is quite similar to a formula for free recoil set out at http://en.wikipedia.org/wiki/Free_recoil, although I think that the formula from Wikipedia may be a little more precise based on what I've read in Hatcher's Notebook. The formula I've reproduced above, is from the Q&As at http://www.frfrogspad.com/miscella.htm (specifically the question about why some guns of the same caliber kick harder than others). John Schaefer (FrFrog) notes that, "..."4000" is the nominal velocity of the powder gases at the muzzle for commercial smokeless powder and the observed range is between 3700 and 4300 f/s. It is sometimes stated as 4700 in some sources but this is based on observations of artillery, not small arms...." The Wikipedia formula would use the actual powder gas velocity, which may not be readily available.
 
My wife is going to become my shooting partner and that makes me a happy oldtimer.
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You'd better be careful

I started letting my wife shoot some of my guns, and even put her on her first deer, and the next thing I knew she started calling them "hers" and I had to ask to use them, or buy more so I would have one to use when I wanted ;)
 
I don't think all of this fancy calculating and figuring means a lot. In my youth in the 60s, the gun of choice for us country folks was a single shot shotgun in 12 or 16 gauge. Some of the shotguns kicked much worse than others even when we used the same ammo. The amount of kick (recoil) felt was based on the gun (mainly stock) and the weight of the gun. My Dad had a shotgun that didn't kick really bad and I had a 12 gauge that people only shot once because it kicked much harder.

Shoot the same ammo in a LCP and a TCP and you will find a big difference in the recoil and comfort between them. They are a similar size and weight.

Shoot the same ammo in a Glock 19 and a Hi-Point C9. The much heavier Hi-Point has far less recoil than the Glock.
 
for the better half

Okay now, be careful what you do with this knowledge.

If you're trying to convince her of something with these numbers and formulas, it could backfire. If she likes something, she likes it. If she doesn't, try something else. I'm still learning this the hard way because I'm stubborn and I hope I'm curable. Or at least it can be put in remission.
 
I understand the concept that the powder charge add mass to the equations and therefore contributes to the felt recoil, but I have a few questions.

Regarding the different in powder charge weight making a difference, wouldn't the type/formula make a difference also? If essence what I am asking is do some powders produce more energy per pound? I realize some produce their energy at faster burn rate causing a higher pressure spike, but if you measure the energy created as a function of time and pressure are all powders equal?

If you could measure the pressure a small amount of powder burned and the time it took to completely burn it all could you get something like this example?

powder A 1 grain yields 1000 PSI in .1 seconds = 1000/.1 PSI/Sec = 10000

powder B 1 grain yields 500 psi in .05 seconds = 500/.05 PSI/.05 = 10000


I understand that if you accelerate a bullet to the same speed in the same amount of time the recoil in the opposite direction should be the same. If I had two different powders like in the example above would the recoil be the same.
 
Isn't the correct equation this from Newtons second law:
Second law:
The vector sum of the external forces F on an object is equal to the mass m of that object multiplied by the acceleration vector a of the object: F = ma.
which transposes to:
(Bullet mass X Bullet acceleration)+(propellant gas mass + propellant gas acceleration)= gun mass X gun acceleration.
 
The felt recoil or kick isn't the same thing as actual recoil. The actual recoil has to do with that Newton guy. Felt recoil has to do with a bunch of factors that can be subjective. No arithmetic involved either.
 
There are 2 factors in firearm recoil equations - the first is primary recoil. Momentum will cover that (mass x velocity of bullet plus gun weight).
The second phase of recoil -secondary recoil- is related to the powder charge weight. The expansion ratio of smokeless powders is a constant -it doesn't matter what powder, only how much is in the cartridge. This is the 'rocket effect' ... it's like holding onto a bottle rocket. You only have to watch a slow-mo of a gun firing to see this effect. I use the link jmr posted to calculate recoil.
If I managed to upload my graph, these are the recoil and energy calculations for my standard handload of 3.6g reddot and a 160g bullet. I weighed the LCR with 4 loaded rounds, the 686 with 5, and the rossi was empty.

All that said, this is just a number. The ergomatics of the gun probably matter as much as the math.
 

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The felt recoil or kick isn't the same thing as actual recoil. The actual recoil has to do with that Newton guy. Felt recoil has to do with a bunch of factors that can be subjective. No arithmetic involved either.
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True, but the OP was about different bullet weights/charge levels/velocity from the same gun so any effect caused by differing grips & so on would be negated as they'd always be the same within his framework for the question.
 
The felt recoil or kick isn't the same thing as actual recoil. The actual recoil has to do with that Newton guy. Felt recoil has to do with a bunch of factors that can be subjective. No arithmetic involved either.
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^^^^THIS

Felt, aka "kick" is a factor of gun fit - whether handgun or long gun. Big person vs small one; big meaty hands vs. small thin ones, the way of gripping the gun, etc.
 
Okay everyone. I received the 2 boxes of 50 shells ammo by Magtech that I ordered
from Lucky Gunner. The one I was really interested in was the 38 CBC special short 125 grain LRN for my wife to use. Last time she shot was 6 or 7 years ago when she went for her permit to carry and qualified with a Taurus 38 spec Ultra lite Titanium 5 shot . Killed her hands and her interest in shooting and never . She was the only female in her class and she outshot everyone by a huge margin. The range Master was flabbergasted. But, because of the extreme recoil, she never
picked up a gun after that. I made her a deal she couldn't refuse and ordered the shorts for her lCR 357 with CT laser grips. It's the damn grips that's causing
all the problems because the grips do not have by any means the ability to mitigate the harsh recoil. Even I could not get passed this.
Well, SURPRISE SURPRISE SURPRISE. It worked. Happy wife ==== happy marriage.

Doc
 
Doc Holliday 1950 said:
...Last time she shot was 6 or 7 years ago when she went for her permit to carry and qualified with a Taurus 38 spec Ultra lite Titanium 5 shot . Killed her hands and her interest in shooting and never ...
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One more illustration that a very light gun isn't always the best idea. They are great to carry, but not so great to shoot.

On my trips to Las Vegas I'll usually carry my S&W 442 (snubie with an alloy frame). I shoot it regularly and qualified with it the last time I renewed my Nevada CHL, but it is just plain nasty to shoot.
 
Well. I'm so used to carrying a 4" as my go to gun, that as long as I'm not swimming or on the beach, I'm ok. I toyed with the idea of getting the 3" 357
but I just really like how the 4.2" Ruger shoots. The weight doesn't bother me, It's just that I have to be very careful how i position it when I carry it inside the waist holster. I think my next purchase will be an all steel 2" and the heck with today's modern tech on steel/poly.
 
The proportions of my 3" 60-15Pro .357 J-Frame and my 4-1/4" 69 .44mag L-Frame are very nearly the same ... if you see a picture of either one by itself, without anything to provide a scale, they are heard to tell apart. The 69 is much larger and heavier, of course, but the proportions are very similar.
 
"Does muzzle Velocity and Muzzle Energy relate to felt recoil or kick?......

Also, does the weight of the bullet affect the two forces or is it strictly MV and ME"?
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All else being equal the greater the velocity, the greater the recoil.

All else being equal the greater the bullet weight, the greater the recoil.

Recoil is a function of bullet weight (more = more recoil), bullet velocity (more = more recoil), the jet effect of the propellent gasses (more = more recoil) and finally rifle weight (more = less recoil).

Felt recoil is measure of how comfortable a rifle is to shoot and is a function of stock fit and padding. Take two rifles with the same weight and ammo. Recoil will be the same, but felt recoil on a rifle with a crooked stock and a thin steel buttplate will be much more than on a rifle with a straight stock and a nice thick pad.
 
I profess that I am not a physics guy--though I get the gist of what has been said so far. I think there might be something else going on with many handguns that hasn't been mentioned yet--and that is the "ergonomics" of how the recoil is "delivered" to the hand.

For example--I have a pet theory that depending on where you grip the gun and where the centerline of the bore is relative to where your hand is--the fulcrum point of the recoils' force may be magnified such that it is harder to keep the gun steady--thus leading to the impression of a heightened recoil force. I've also found that "reachy" triggers can aggravate this. I could be wrong too. ; )
 
StagPanther said:
I have a pet theory that depending on where you grip the gun and where the centerline of the bore is relative to where your hand is--the fulcrum point of the recoils' force may be magnified such that it is harder to keep the gun steady--thus leading to the impression of a heightened recoil force.
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A lower grip definitely affects the felt recoil, but I personally prefer the nature of the recoil with that low grip ... I don't aspire to fast follow-up shots, so a lot of muzzle-rise is a good thing for me, not a bad thing. When combined with my very relaxed hands, wrists, elbows, and shoulders, very little of the felt recoil makes it back to the rest of my body ... the felt recoil gets soaked up just by the mass (and hence inertia) of my arms, and doesn't jar my brain, eyes, teeth, neck, etc. But people who are trying to resist muzzle-rise, by using a very firm grip, so that they can get quick follow-up shots, probably dislike a high bore axis and a low grip.
 
The grips themselves also play a role, not just on how you grip them, but what they are made from. Pachmayr, Hogue and others have made fortunes from rubber grips as they give under recoil and do not transmit as much directly to the hand as solid wood or metal might.
 
FITASC said:
[...] rubber grips as they give under recoil and do not transmit as much directly to the hand as solid wood or metal might.
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It's not that they transmit less momentum to the hand ... it's that they spread that recoil over a larger surface area (less pressure), and also (probably more important) the recoil is spread over a longer time interval, so that the hand has more time to absorb it ... the recoil is less "sharp".
 
Just ordered the Hogue Tamer grips for her LCR. It will be here Friday. I expect that this will solve most of the issues that have come up with firing a snub. I'd like to thank everyone's input on this. You have all helped.
Doc
 
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