muzzle velocity for recoil

[tipoc]

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.

Well that's part of it. If the weight of the bullets are identical the faster bullet will generate more energy and thus more recoil force. Basic Newtonian physics. It takes more energy to move the bullet faster, thus more recoil.

The physics you should study some. But shoot more to see the reality of it and this will deepen your understanding. It helps to see the variables in action. This is why some of the accurate information here may seem contradictory.

tipoc

 

[keegan]

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 was confused with table 1. Are they saying if they use the same amount of gun powder which is 5 grain, those velocities is where each round would be at for each weight?

Is table 1 also saying with 5 grain of gun powder, it is achievable to reach 165 power factor for each round ?

 

[74A95]

Table 1 is meant to show that, IF the different bullet weights used the same 5 grains of powder weight to achieve their required velocity to produce the same power factor, they would produce the same recoil force.

But they don't, at least not if you use the same gunpowder. The same powder charge weight (using the same powder) does not produce higher velocity with lighter bullets. It usually produces less velocity, and it certainly results in the lighter bullets producing a much lower power factor, which is shown in Table 2.

Light bullets need MORE gunpowder to reach their required higher velocity (Table 3). Because of this, when you do the math (or use a Ransom Rest), the lighter bullets end up producing slightly more recoil force than the heavy bullets to produce the same power factor (when using the same gunpowder).

If you put a compensator on the gun, the results are reversed, and lighter bullets produce less muzzle rise than heavy bullets. More powder weight means more gas and gas pressure. More gas pressure pushing up via the compensator (or ports) causes more force pushing down via Newton's third law. That's why a lot of competitive shooters use light bullets in their compensated race guns. http://www.shootingtimes.com/reloading/power-factor-recoil-bullet-weight-compensators/

 

[tipoc]

I would avoid the articles on this by Brad Miller. The articles are self contradictory and often based on false premises. To cite just one example is the idea that a good way to measure recoil is to judge how far a gun moves when clamped in a Ransom rest. That really tells you not much for the purposes of this discussion.

Standard formulas on recoil are based on good formula and are accurate for what they do show. They show mechanical recoil. That is based on Newtonian physics that for every action there is an equal and opposite reaction. So the formulas will tell you how much force from the burning powder will show up as an equal force moving rearward as recoil. The factors here are the weight of the gun, the burning rate of the powder (hence the rate of expansion of the gas), the weight of the bullet, etc.

It will tell you nothing about perceived recoil or how it is felt to the shooter. It can't. The formulas are more applicable to long guns and artillery than to handguns. They were developed for artillery and long guns.

The mechanical recoil force will be the same whether a gun is compensated or not. It will be the same whether the gun has a long or short barrel. It will be the same whether it's a revolver or pistol.

Felt recoil, or how that force is perceived, is different. Very different. That's effected by a variety of factors.

I encourage you to get a hold of Rinker's book. Or Hatcher's writings on this subject.

These two articles may be of some help to you.

http://www.thetruthaboutguns.com/20...n/measuring-recoil-comparison-pistols-part-1/

https://www.chuckhawks.com/handgun_recoil_table.htm

tipoc

 

[74A95]

I would avoid the articles on this by Brad Miller. The articles are self contradictory and often based on false premises. To cite just one example is the idea that a good way to measure recoil is to judge how far a gun moves when clamped in a Ransom rest. That really tells you not much for the purposes of this discussion.

The Ransom Rest (RR) is a dumb machine. Its movement is based on force that is applied to it. More force = more movement. That author compared RR movement to the mathematical model and it compares favorably. http://www.shootingtimes.com/ballistics/measure-relative-handgun-recoil/

I see no contradictions or false premises. The Ransom Rest results in the article on power factor and bullet weight (Figure 3) are compared to the mathematically calculated recoil force (Figure 4) and they look the same. That suggests the RR's movement is a useful tool for measuring relative recoil force.

 

[tipoc]

In the article I linked to by Zimmerman they use the movement of a laser to account for recoil based on the jump of the muzzle during firing. But they also explain that it is not exactly scientific and explains why. Here they are a bit more careful and honest than Miller. Zimmerman also has the advantage in knowing that he is only giving a rough explanation which can help some folks understand the difference but is only that.

Miller's experiment has no actual meaning beyond what it is. It shows how much a Ransom rest jumps.

The best way to learn is to go and shoot.

tipoc

 

[74A95]

In the Zimmerman article the gun was hand-held. This is not an objective measure of gun movement. It is subjective and they describe it as “with no particular effort to control the recoil”. The only way it would be valid is if they MEASURED the resistance the shooter applied to the gun hand/arm/shoulder etc for every shot. He didn’t. I don’t know how that would even be possible. With all due respect to Zimmerman, the results must be taken with a grain of salt because he has not accounted for the biggest source of variation that can contribute to gun/dot movement - how much resistance is applied to the hand-held gun.

A difference shooter could get different, contradictory results. Hence the problem with hand-held shooting.

The Ransom Rest is a mechanical device that is objective, not subjective like a hand-held gun. The RR offers the same resistance for every shot. Its movement can be measured. Its movement can be statistically compared via correlation to velocity, which the author did in the “how to measure relative recoil” article. Its data can be compared to the mathematical model for recoil. The Author did that and discussed the meaning of the results. The actual movement data was shown as were the statistics. How much more honest can you get????

 

[tipoc]

In the Zimmerman article the gun was hand-held. This is not an objective measure of gun movement.

Sure and that's the point, Zimmerman explains that and the limitations of it. This is the value of Zimmerman's report.

Miller's test is certainly objective or objective-ish. But then so are EPA ratings of mile per gallon for a motor vehicle. The EPA rests the driving wheels on a piece of test equipment indoors in a lab and measures the speed of the vehicle and how much gas is consumed per mile of travel on an indoor apparatus. The test results are valid only and just for that, average MPG on a piece of lab equipment on an indoor track. Those tests do not transfer to actual driving conditions and actual average MPG. They can't.

The tests by Miller show you only what they show you. How much movement there is in a Ransom rest when a gun is fired with x bullets and x loads. Based on his testing which may or may not be more or less rigid. That's all they show. Only he does not explain that simply. It is as vague as a mathematical formula, more so.

We don't all have Ransom rests. We do have handguns. We know from experience that the felt recoil from a Walther PPK in 380acp is stouter than the felt recoil from a Sig P238 in 380acp with the same loads and weight bullets. Even though the formulas show us that mechanical recoil is less in the heavier Walther. This is due to the fixed barrel of the Walther vs. the tilt barrel of the Sig P238...the construction of the pistol.

So go shoot and learn this for yourself. Shoot a M1917 in 45acp and a 1911 in 45acp side by side and feel the difference.

tipoc

 

[jrothWA]

It's simple, it DEPENDs on the shooter perception!

my wife cannot shoot a Woodsman using standard velocity .22 LR ammo.

Both daughter love it.

youngest has a LCP, eldest has 2" Charter arms.

Pick a comfortable feeling sidearm and practice with lowest velocity ammo until itis second nature.