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Recoil
Gene B.
Member Posts: 892 ✭✭✭✭
How much recoil does the Springfeild 45 acp and the S&W 1911DK 45 acp have?
Comments
The recoil really depends on the gun. The recoil on the Sig 226 was almost nonexistant. I compare it to my 10/22.
The Ruger has more of a snap than the Glock 40 or 45. They both have a very smooth feel. Instead of you hand snapping around your whole arm moves very fluid.
NIKLASAL@hotmail.com
PC=BS
lets all be responsible! shoot a criminal!
Evert action has an equal and opposite reaction. Recoil is the reaction from the action of the bullet (and powder) leaving the muzzle. The reaction to 340 ft/lbs is less than the reaction to 320 ft/lbs. Ergo, the .45ACP recoils LESS than the 9MM (in standard loadings).
Quod principi placuit legis habet vigorem.Semper Fidelis
Margaret Thatcher
"There are three kinds of lies: lies, damned lies and statistics."
Mark Twain
Shootist, you know 100 times more about guns than I do, but my calculations come out a little differently. For bullet weight in grains and velocity in ft/sec, the formula for kinetic energy of the bullet is m*v*v/450450 in ft-lbs. m is the mass of the bullet, v is the velocity. For the 9mm I get 115*1155*1155/450450 = 341 (approx) and for the .45 I get 230*830*830/450450 = 352 (approx). You can also use the table in the following link, but you'll have to interpolate: http://www.naaminis.com/energy.html .
Now, the energy in the bullet is interesting, but that isn't going to give you the recoil. The recoil will depend on the momentum of the bullet and the gas. The momentum of the bullet is easy to calculate, just m*v, but the momentum of the gas needs an estimate of the mass of the gas in grains and its average exit velocity out the muzzle. But just for the sake of the example, the 9mm bullet alone has momentum = m*v = 115*1155 = 132,825. The .45 bullet momentum = 230*830 = 190,900. The gas will add something to both numbers in the range of 25%. But in any case, the .45 carries more momentum.
But wait, we aren't done. In order to project that much momentum forward, the gun has to kick back and present the shooter with an impulse equal to the momentum. Impulse is force times the time the force is applied. It's actually more complicated than that, since for any gun the graph of force versus time is not a simple line. So a better definition of impuluse is the area under the force versus time graph. The shape of that graph will depend very strongly on the action of the gun. If the gun's action can stretch the force out over a longer period of time, the peak of the curve can be less because what counts is the area under the curve. This is why some 9mm will feel like they have a short and sharp kick to them while some larger calibers will feel like a lower force that lasts a longer time.
Here's a good example that everyone can relate to. If you are in a car going 100 feet per second (68 mph) that crashes into a brick wall, you will come to a stop. If you weigh 200 lbs, your momentum has changed from 20,000 lb(mass)-ft/sec to zero. If the car does not have an energy-absorbing front end and you slam into the steering wheel, coming to a stop in 0.001 seconds, the force required is 625,000 lbs. You will die. But if the car has a well-designed front end and an airbag explodes in front of you to slow you down more gradually, say in 1.0 second, then the force required is "only" 625 lbs. You will probably live. The force times time -- impulse -- is the same in both cases, but the maximum force is less the longer that impulse is stretched out in time.
OK, class, time to wake up and take the pop quiz.
PS -- There was a previous thread along these lines: http://forums.gunbroker.com/topic.asp?TOPIC_ID=16006
Margaret Thatcher
"There are three kinds of lies: lies, damned lies and statistics."
Mark Twain
Not sure I agree that ME isn't the critical factor though but I'm sure you are correct (doesn't mean I'm changing my mind, just means I am most likely wrong )
I have always felt that 9's recoil more than .45's
Quod principi placuit legis habet vigorem.Semper Fidelis
Anyhow, the design of the gun is most important with muzzle flip. FOr example, the muzzle flip of my Glock in 40S&W is less than that of my Sig 229 in 40S&W, mainly due to the location of the barrel relative to my hand and the gun's center of gravity. My Sig has a barrel about .5 inches higher than my glock.
The muzzle flip has less to do with the velocity of the bullet as it does the moment of the force. The moment is similar (but not exactly) to torque. IN the case of muzzle flip, the moment is the rotation of the gun about it's center of gravity.
Imagine this... You are shooting in a normal stance, lets say your forearm parallel to the ground, hand and arm PERFECTLY rigid.
...........hand
GGUUNN.hand.yourarmyourarm.....Force
> F=MxA
........GU.hand....................Moment----> Fxd
........NN.........................(d is vertical distance from
................................barrel to arm, in this case,
................................0 lines)
................................Moment= Fx0 = zero ft/lbs
If your arm is in perfect line with the barrel, the total force will only be in the horizontal (x-direction), and you will have no muzzle flip. You will feel everything in your hand/arm. The force equals simply the mass x acceleration of the bullet.
If the barrel is much higher, it would create a moment of force about a point of rotation. Lets say at point X.
GGUUUNN.......................Force
> F=MxA
.........GU.......................Moment----> Fxd
.........NX.hand..................(d being the vertical distance
.........UN.handd.yourarmyourarm...from barrel to X, here: 1 line)
.........GU.hand..................Moment = Fx1 ft/lbs.
What causes muzzle flip is the amount of force at the moment with respect to the point of rotation. In the above case, when the gun fires, it creates torque about the X. The greater the moment, the more the muzzle flip. The less the moment, the less muzzle flip.
Sorry about the crude drawing. Don't have scanner yet.
NIKLASAL@hotmail.com
Edited by - niklasal on 04/22/2002 08:20:01
I still say Glocks are ugly, I don't care how well they shoot!
Clouder..
I feel WAY more comfortable with the .40 cal as opposed to the 9mm.
Given my choice i'd carry a .45 auto any day.
"We become what we habitually do. If we act rightly, we become upright men. If we habitually act wrongly, or weakly, we become weak and corrupt" - *ARISTOTLE*
**Like Grandad used to say--"It'll feel better when it quits hurtin"
Interestingly, H&K used a reverse rotation(counterclock wise) rifling to minimize torque twist for right hand shooters since most shooters are.
Nikasil, I had one HP 5300 Scanjet that didn't work. Then they sent me another.
Now, I have two...that don't...work.
Want to trade something?
Happy Bullet Holes!
NIKLASAL@hotmail.com
It makes no sense to ask about recoil between two calibers unless one discusses a specific round and uses the same gun model. In the first place, you've got Magsafe and Glaser advertising much higher velocities and stopping power, but even in the more conventional civilian-available ammo there's everything from a slow .45 230-gr load to a high performance 230-gr load to a CorBon 165-gr load that leaves a barrel about 1150 fps on average. CorBon's 9mm 115-gr velocity is even higher than their .45. And .40 loads come in at least 3 weights, 135, 165, and 180, at different velocities.
Barrel length and gun weight affects perceived recoil, and grips play a huge role too. Example: My Bulldog Pug .44 hurt the web of my hand after serious shooting time. I finally bought some Pachmayrs for it and found out why: The standard grippers that Charter makes are only as big as Pachmayrs Compac grip, and to top it off, the rubber in the web of the hand, while about 1/8" thick on the Charter grip is about 1/2" thick on the Pachmayr. Guess which grip will hurt less?
Then of course there is the question, what does recoil signify to you, merely pain, or a quick follow-up shot? If follow-ups are the concern, then what we are really concerned about is not recoil but muzzle flip -- a different factor, slightly. Muzzle flip can also be affected by grip design, handhold, load power, barrel length and weight, and porting. But, it's another topic.
-- Life NRA Member
"If dishonorable men shoot unarmed men with army guns, the evil must be prevented by the penitentiary and not by general deprivation of constitutional privilege." - Arkansas Supreme Court, 1878
SSG idsman75, U.S. ARMY
Did they hold it sideways and throw signs with the other hand?
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