Graph: rifle cartridge muzzle energy and momentum factor

[krispos42]

They go in order increasing bullet diameter, small on the left, big on the right.


I converted the recoil (momentum) into ounces from grains (437.5 grains in an ounce) so the two data values would be similar in numerical value and chart nicely.


All the cartridges shown here are commonly available in both rifles and ammunition.

Information taken from Winchester Ammunition's website. Whenever possible, I picked a bullet weight from the middle of the available offerings.


The US uses .223 Remington in the M16 and M4 rifles and .308 Winchester in our M14 rifles and M240 machine guns. The AK-47 and SKS rifles use 7.62 Soviet.

Feel free to use this chart in other postings.

[konnichi wa]

1. My 50 year old Winchester 30.30 'varmint/brush gun' is more 'powerful' than an AK47

scary-looking 'assault weapon'. Oh wait, I knew that.
;-)
\

[doc03]

2. My 30-06 Springfield rifle developed way back

1906 is much more powerful than any of those scary assault weapons calibers. That seems to be a common belief that the so called assault weapons are some kind of super powerful cartridge.

[spin]

5. Bullshit promoted by the M$N and gun control groups...

to promote their agenda.

They want people to believe that "assault weapons" are high powered fully auto weapons. It's like calling a V8 powered car a NASCR racing vehicle.

Obviously, they believe people are stupid. People tend to resent being misled. A little education can go a long way and perhaps posts like yours can change the opinions of a few people, who in turn can influence other people who have little knowledge of firearms.

[krispos42]

22. It's the rounds per second that makes them unhappy

And the shots between reload, And the quickness with which they can be reloaded, that they are worrying about.


Yes, a lever-action gun can shoot about as fast as a semiauto, but they can't hold more than 10 rounds or so and they take a long time to reload.

Yes, an SKS or Garand can shoot as fast as an AK-47 or AR-15 and be reloaded quickly, but they only hold 10 rounds or less.



Unfortunately, what makes a gun good for defense also makes it good for offense. And it's something that drive the anti-gun people to fustration.

[spin]

24. So a fair argument could be made by the gun control advocates...

that firearms with detachable magazines should be banned or that magazine capacity should be limited.

Of course, the practicality of making all the current firearms with detachable magazines illegal or requiring them to be licensed and register similar to fully auto weapons, is one hell of an obstacle.

But when the M$N shows a fully auto weapon being fired on a target range and talks about a ban that would apply to semi-auto weapons, it's obvious that they are attempting to motivate those who don't understand firearms to support their agenda. It like showing a picture of a NASCAR vehicle on the track in the background while the news clip discusses outlawing V8 engines to reduce traffic fatalities.



Both sides of this issue have valid arguments. It would be beneficial to discuss it in a civil manner without resorting to propaganda and exaggeration. These are tactics used by both sides and do little to solve the problem of firearm violence in our country.

[krispos42]

29. Well, they could...

...but the spirit of invention can work around them.


For example, strapping two or three 10-round magazines so they're side-by-side makes changing magazines very quick. Simply yank out the mag cluster and re-insert it one magazine over.

Handguns already can be reloaded pretty quickly. Hand naturally finds hand, which when combined with the easy loading of a tapered double-stack magazine makes quick reloads pretty easy if you practice. And handguns that drop their mags help even more.

I've seen quick-reloading tubes for shotguns. Insert one end into your pump or semi-auto shotgun and push forward on a plunger. The tube's plunger shoves the rounds quickly into the tubular magazine. Presumebly they could make them for side-loading lever-action guns as well, like cowboy-action-style .357 and .44 Magnums.

Revolver that use full-moon clips are very easy to reload. Simply drop in a new load, close the cylinder, and start shooting.



Fixed-magazine guns reload pretty quickly as well. There's no magazine or mag release to fumble with. When the gun stops, grab a stripper or en blocclip full of fresh rounds, and shove it down into the magazine, and slam the bolt closed.



There's no magic solution, really. We would have to revert to something like a muzzle-loader to get the potential rate of fire down enough to maybe reduce the Virginia Tech or Columbine-style shooting. Absent of a quick police response or decisive action by the intended victims, even a guy with a break-action shotgun can get off 10 rounds or more a minute.

[east texas lib]

3. Interesting...

Is this the initial energy @ the muzzle?

[krispos42]

4. Yup, that's if you're unlucky enough to have the gun barrel in your ribcage

Ouch. :-(

[east texas lib]

6. I would've thought the 45-70 would have more energy...

From the way my Marlin 1895SS kicks, anyway. Thanks for sharing the graph, as we still have dial up
out here and just downloading pictures takes an act of Congress!
On edit: I use 400 Gr ammo. That certainly accounts for the recoil.

[krispos42]

8. recoil is mass times velocity. Energy is half-mass times velocity squared

If you double the velocity of a bullet, you double the recoil but quadruple the energy.

If you halve the bullet weight but double the velocity, you have the same recoil but twice the energy.

Example:

You have two cartridges, the .45-70 and the .35 Whelen.

Remington makes a 200-grain load for the .35 Whelen with a muzzle velocity of 2,675 ft/s, and a 405-grain load for the .45-70 that leaves at 1,330 ft/s.


So the .35 Whelen is halve the weight at twice the velocity. Same recoil, but according to Remington, the .35 had a muzzle energy of 3,177and the .45 has 1,590.

1,590 x 2 = 3,180

:-)

They'll both kick about the same, but the .35 delivers more energy for the kick.


Of course, the .45-70 makes a bigger hole... :-)

[Tandalayo_Scheisskopf]

7. Now...

How about some Hatcher Scale?

[krispos42]

12. Can't find a good formula for it

The two I've been able to find don't make any mathmatical sense.

http://www.abaris.net/info/ballistics/hatcher-table.htm

This doesn't help because when you run the numbers through, you don't get what's calculated.


It's suppose to be either momentum or kinetic energy times bullet frontal area times a form correction factor. HI=M*A*F


For a .22 LR, the table gives a bullet weight of 33gr, a velocity of 1500 ft/s, a muzzle energy of 165 foot-pounds, Lead Round Nose correction factor of 1.00, and a Hatcher Scale number of 4.332.

The frontal area of a .22 is .038 in², so 4.332 = M * .038 * 1

4.332 = M * .038
114 = M

But where does the 114 come from?

I did some more playing around with the numbers (I'm writing as I research), and if you convert the bullet weight from grains to ounces (not pounds) and multiply it by the velocity you get 113. That's close enough if you give me and them some slop for rounding errors.

Okay, then, "M" is bullet weight in grains, divided by 437.5 (to convert into ounces), then multiplied by the velocity.
M = Bw ÷ 437.5 * V

Yeah, okay, that works. He's using bullet weight in ounces. I tried it in a .38 listing and it came out pretty damn close.

I'll make a chart and post it in this thread as well.

[krispos42]

14. Hatcher Index, as requested

Interestingly, it's suppose to be a minimum of 20 for self-defense, and the .223 Rem lists at about 16. Hmmm...

Of course, the Hatcher Index is suppose to be for handguns, but it makes for interesting debate.

[ConcernedCanuk]

9. Something very wrong with that chart - 22-250

.
.
.

I got one - barrel is 1-1/2 thick - gun weighs nine pounds - built by an ex OPP officer up here (now deceased)

Only gun I now own -

previously I had a .308, numerous 22's . bolt and semi automatic

back to the 22-250

It has a muzzle velocity of over 4500 feet per second

yeah - that's almost a mile in one second

Target shooting with it at 300 yards I could hit a one inch circle at least once in a three round shooting

Always within 3 inches after zeroing in

It's what they call a "bench rest" target gun

totally useless for hunting

but accurate as heck!

[doc03]

10. Totally useless for hunting? The 22-250 is about the

best woodchuck, prairie dog and coyote rifle made isn't it?

[ConcernedCanuk]

11. A REGULAR 22-250 is a great varmint gun - but it's barrel is not 2" in diameter

.
.
.

A normal 22-250 weighs less than 3 pounds - my gun weighs almost 10 pounds

It was designed for target shooting

Homemade by a gunsmith - mauser bolt action with a 3 shot magazine

clip capable I believe, but never checked that out - no need - I use it for target practice only.

Well,

unless the USA invades us . . .

:silly:

[doc03]

13. People used to use them around here

years ago, we had thousands of acres of open strip mine areas that you could hunt. All that land was either sold off in small plots for hunting camps or for large beef cattle farms. Those areas are all posted today. My dad wouldn't have thought of shooting a groundhog closer than 200 yards, he used a heavy barrel Sako .243.

[TXRAT2]

16. A normal 22-250 weighs less than 3 pounds

Your info is very questionable.

[ConcernedCanuk]

19. Thank you - you are correct, a normal 22-250 weighs around 6 pounds

.
.
.

My "Heavy Barrel" model weighs over 10 pounds



and would cost over $1000 to buy today

wow!

yeah - I did some research

If you check the link out, you'll discover that most of the Heavy Barrel models are out of stock

I think I got a keeper!

Thanks again

:thumbsup:

[TXRAT2]

15. 4500 fps with what weight bullet?

[ConcernedCanuk]

20. I honestly forget now, I used to have a gun shop do reloads for me

.
.
.

I had a book that had a formula for the bullet weight and the number of grains of powder.

I think I was maxed out on the powder, maybe a wee bit over.

Some of the brass used to "neck" after only one or two reloads.

I don't do reloads anymore, never learned how to do it myself, and the reloader I used went out of business - so I use factory stuff now.

I haven't target shot for over ten years now, still have the gun, lost the scope somehow, and just clean it and fire it a couple of times a year now.

Scope was a 10x50 Tasco with parallax adjustment - I took it off to use it for a telescope one summer, then lost it

(sigh)

[krispos42]

21. I've seen that velocity from the .223 WSSM...

... with like 40gr bullets.

If memory serves the bullet was spinning so fast from the barrel it would rip itself apart inches from the muzzle!

[TXRAT2]

25. I'd love to see these loads y'all are talking about

I've got over 40 years behind bench-rest and varmint rifles, from 220 Swifts, 22-308 and even a 22-284 and I've never seen those kind of velocities, but then again we didn't have anything lighter than 50 grain bullets available. Right now I carry a 204 with a 32 grain bullet at 2250 fps.

[TXRAT2]

26. My mistake, that should be 4250 fps.

[krispos42]

28. I read about it in a magazine shortly after the WSSMs came out

Hmmm... maybe "Guns&Ammo"?

Or it might have been something like "Peterson's Hunting" or "Field & Stream".


I remember the article talking about how the velocity of propogation of gunpowder was 5,000 ft/s, so that was the theoretical maximum velocity of any projectile propelled by gunpowder.

[one-eyed fat man]

31. M256 tank gun and muzzle velocity

The 120mm gun we have on the M1A1 tank fires ADFSDS-T M829 at a muzzle velocity of 1580 m/s which works out to 5200 fps. Even the old M392 series APDS-T we fired out of the M68 105mm gun on the M60 series tanks in 1959 had a muzzle velocity of 4850 fps. The propellant is an extruded stick type triple-base smokeless powder consisting of nitrocellulose, nitroglycerin, and nitroguanidine.

Rhinemettall has developed a round for the L55 version, the DM63 which is even faster at 1,750 meters per second (5,700 ft/s). But with chamber pressures upwards of 80,000 psi the fatigue life of the tube is short at 400 rounds.

As far as accuracy goes, both of those guns will normally shoot under .25 mils which is sub-MOA. Knocking the turret off an Iraqi T-72 at 5 km was no big trick.

[krispos42]

32. Is tank propellent the same as regular gunpowder?

There's suppose to be a difference between the "triple-base" artillery propellent and "double-base" firearm propellant.


Or the guy writing the article I sorta remember had it wrong :D

[one-eyed fat man]

33. single, double, and triple- base

Define the basic compounds used to provide the "energy" in the propellant. Nitrocellulose is the basic ingredient for most smokeless propellants. Nitroglycerin is used in double-base powders to add "energy" while nitroguanidine is a component of triple-base formulations. Single- and double-base propellants are common in handgun and rifle ammunition. Triple-base propellants are more common in artillery.

Additional ingredients may include:

Plasticizers, to make the grains less brittle.

Binders, to hold the grain shape.

Stabilizers, to prevent or slow down self-decomposition.

Decoppering additives, to hinder the buildup of copper residues on the rifling.

Flash reducers, to reduce the brightness of the muzzle flash, but usually have the disadvantage of producing smoke.

Wear reduction additives, to lower the wear of the gun barrels.

Graphite, is often used as a lubricant to cover the grains and prevent them from sticking together, and to dissipate static electricity. Calcium carbonate is used to neutralize acidic decomposition products. As a side note, it was the very high percentage of calcium carbonate initially used in Ball powders that was responsible for the rapid clogging of M16 gas tubes 50 years ago.

Faster-burning propellants generate higher temperatures and higher pressures, however they also increase the wear of the gun barrels. Slower propellants may ultimately impart more energy, but need more time, that is, a longer barrel to achieve that result.

The properties of the propellant are greatly influenced by the size and shape of its grains. The surface of the grains influences the speed of burning, and the shape influences the surface and its change during burning. By selection of the grain shape it is possible to influence the pressure vs time curve as the propellant burns. This is another of differences between cannon powders and small arms powder.

Another aside, Ball powder was initially developed by Western Cartridge, a subsidiary of Olin Industries, in 1933 as a way to recycle cannon powders left over from WW1 into small arms propellants cheaply and in volume. However, it was not accepted by the U.S. Army until 1944.

Getting the right mix is very much a black art and a reason why performance can vary significantly from lot to lot. Canister grade powders as used by reloaders is generally more consistent than the powder lots used by arsenals to load ammunition. Arsenal operations each powder lot is tested and the powder charge is tailored to produce the the ammunition performance needed.

[benEzra]

34. You can use a lower twist rate to keep the 40-grainers from disintegrating.

You usually see disintegration when you use faster barrel twists more suited for something slower, like .223.

4500 feet per second and a 1 in 7 inch rifling twist would have the bullet exiting the muzzle spinning at over 460,000 rpm. A 1 in 12 inch twist rate would reduce that to "only" 270,000 rpm.

[BigBluenoser]

17. Great graph - but now a request...

Any chance you could toss the 8mm Mauser, 7.62 Russian (7.62x54R), and the .303 British on there for this lover of Mil-surp?

Cheers.

[krispos42]

18. Nah, but it's easy to calculate

Muzzle energy is bullet weight (in grains) times velocity (in feet per second) squared, divided by 450,240.

E = w * v² ÷ 450,240


The momentum that I'm using is based on used the ounce as the unit of weight, not the grain. For that, it's bullet weight (in grains) times velocity (in ft/s) divided by 437.5

M = w * v ÷ 437.5


You can use any momentum system you want, as long as you're consistant.



Although I must note that the momentum impacted on the rifle is more than just bullet weight times bullet velocity. You're also expelling a sizable weight of burnt propellent. For a .30-06, you're adding about 50 grains to the payload, increasing felt recoil by nearly a third.

However since powder charges vary significantly by cartridge, powder type, and bullet weight, I just stuck with "known knowns", as Rummy would say. The momentum here is what somebody a foot from the muzzle would feel as the bullet was absorbed by his body.

[Mercracer]

23. Another thing to consider is SD

2 bullets with the same energy are not necessarily equal. When you are looking at penetration, the bullet with the higher Sectional Density will be the one which will likely penetrate easier. Also, a light bullet going really fast may have the same or more energy as a larger/heavier bullet going slower but will often not penetrate as far into the object. The faster lighter bullet will likely loose velocity quicker as it penetrates.

[krispos42]

30. True, that.

Doesn't matter too much for humans because we're upright and thin-skinned, but trying to take down something angry and 4-legged... yeah, it matters.

[Tim01]

27. And that's why I love my .458 Win mag. nt