Muzzle Energy vs Recoil vs Rifle Weight for Dangerous Game

[Luvthunt]

Taylors KO theory has been a controversial number for awhile. Many people feel Harchers calculation for KO to be truer to reality.

 

[MS 9x56]

The only thing more speed has gotten me is a bigger scrap pile of bloodshot meat.

 

[Jim Golden]

Kinetic Energy = 1/2 MV^2
Momentum = MV

So really, they're both velocity dependent. I will agree that once you start getting up there in velocity that it does blow stuff up. I really like the .264 Winchester on deer, but it blows them up much more than a .270 Winchester does. I use a .270 Weatherby a lot and it and the .264 are about equal on blood shock. You have to be careful with shot placement or you'll lose a lot of meat.

And as said above, the old .45-70 (I have a Ruger No. 1 and a Marlin 1895 Cowboy in that) hits them harder all out of proportion to what the ballistics say. I guess it's like chucking a cinder block at them. I load a 350gr Hornady to about 1850 ft/s in the Marlin. I've only shot one deer with it, and he did run 50 yards (it was a good shot) before he dropped (the .270 Wby and .264 usually kills them before they hit the ground), but the internal carnage from that big chunk of lead was as bad if not worse than anything I'd seen of the other two. Went in through the lung area, must have hit the far shoulder and turned 90 degrees left and headed aft, hit something back there and turned 90 degrees right and tried to exit out the rear hind quarter. I recovered the bullet sticking out the hide. I'm hesistant to load the Marlin any hotter than that....sometimes the lever comes loose (might just be me doing it from recoil...). My Ruger has a defect and always has....it goes off sometimes when you shut the lever so I never shoot it. Need to send it back to Ruger....

I'll give Taylor credit for trying to factor bore diameter in there somehow. He tried to quantify something that's not easily quantified.

 

[Ontario Hunter]

The only thing more speed has gotten me is a bigger scrap pile of bloodshot meat.

I'm with you but this is about dangerous game cartridges/rifles. I guess wrecking meat is not a top priority. More important to knock a killer animal down. But it is also important that shooter not get knocked down ... with his gun. Hard to make a follow up shot laying on my back.

 

[grand veneur]

The advantage of a higher muzzle velocity by big bore cartridges is that you have a sufficient impact velocity in the range recommended by the various bullet manufacturers, and this velocity also at a greater distance than the usual one for big game shooting. Many will say; one don't shoot at longer range with a a big bore rifle. That may be true in many cases, but not always, especially when something doesn't go as planned. Having potential reserves is not uninteresting as long as you accept the stronger recoil. This is the distinct advantage of a cartridge like the 460 Weatherby Magnum compared to a cartridge 458 Lott for example. But it does not have to be 2700 fps of muzzle velocity, 2500 fps is more than enough and the cartridge 460 Weatherby Magnum delivers this with absolute certainty, which is not always the case with other cartridges of the 45 caliber class and the 2400 fps expected.

 

[375Ruger416]

Thanks to Mark and others for the spreadsheets. Interesting reading to be sure. ‘All things being equal’ never are. Increase one factor important to clean kills to the extreme (velocity, bullet mass, diameter, etc.) and it has adverse effects upon another or adverse secondary effects - recoil, muzzle blast, cost, unreliable or excessive bullet expansion…

As some of you know from giving me advice on another thread, I have chosen a 375 H&H in a Blaser R8. If I needed more, I think a 404J or 416 of some flavor would be a reasonable next step. Above the .458’s, recoil energy and velocity seem to be excessive for what is gained IMO.

Mark’s table is a great starting point for a survey of the range of DG cartridges. Sectional density is the only addition to the table I would like to see. I realize retained sectional velocity is more relevant for soft bullets, but SD is still a useful metric that is useful for comparison between cartridges. Kevin Robertson emphasizes it in his books and during the podcasts I’ve heard him on.

 

[Tanks]

I'm with you but this is about dangerous game cartridges/rifles. I guess wrecking meat is not a top priority. More important to knock a killer animal down. But it is also important that shooter not get knocked down ... with his gun. Hard to make a follow up shot laying on my back.

Seriously? In what world would one get knocked down shooting a big bore if practiced? Here is a practice session, watch my feet, they don't even move.

 

[Ontario Hunter]

Seriously? In what world would you get knocked down shooting a big bore if practiced? Here is a practice session, watch my feet, they don't even move.

Right. And when dodging a charging buffalo it's always practical to set up a tripod and get feet properly oriented. "Wait there a minute big fella while I get set up. Okay, now I'm ready." Pffft. I sometimes almost lose my footing making second shot on skeet pairs and I'm shooting a heavy magnum auto twelve gauge with just 1 1/8 oz loads. But of course, I'm only 6'1" and 205 lbs. And I typically only shoot that gun a couple thousand rounds at the range every year. If I had to shoot my 404 on the run or backing up, staying on my feet might be a challenge. But same scenario shooting some cannon belching out 500 gr bullets at 2400 fps and likely either me, the gun, or both can easily wind up laying on the ground. But hey, that's just me. I don't change my clothes in a phonebooth. ‍

 

[Tanks]

Well, I am 6' and 180 pounds according to my latest DEXA scan a few days ago. I have shot animals with the .500 off-hand as well. Technique and muscle memory do not change. But, you do you.

BTW, here is video of a buffalo charge. The PH, Dean Kendall, is 5' 7" if that tall and weighs about 160. He is shooting a .470 NE. Didn't get knocked down at all

Charge starts around 0:49.

 

[MS 9x56]

I'm with you but this is about dangerous game cartridges/rifles. I guess wrecking meat is not a top priority. More important to knock a killer animal down. But it is also important that shooter not get knocked down ... with his gun. Hard to make a follow up shot laying on my back.

Saw a buddy try that when his 3 1/2” mag 10 knocked him off his stool.

 

[CZDiesel]

@CZDiesel , I posted the link to shooterscalculator.com at least twice in my posts.
@zephyr , also post the same link for "just such an emergency"


The online calculators make this stuff really easy!

Since we do not know the exact weight of the powder charge in your Hornady factory ammo, I used 70 grains from my H4895 loads. Chances are Hornady's loads are a little heavier on powder, making for a compressed powder charge. It still goes bang!

Also, it is ALWAYS good to clock the muzzle velocity of all loads, factory or hand loads. I've measured some 458 Lott factory ammo where on its box listed MZ of 2300, only to find the velocity was 2150. I am not kidding on that!

View attachment 623261

The chart above with data calculated using shooterscalculator.com , shows your 8 lb. rifle's free recoil energy of 80.5 lbs exceeds that of a 10.5 lb. 458 Lott and is comparable to a 10.5 lb. 470 Nitro Express that burns 60% more powder! Everything traveling down the barrel, i.e. bullet and weight of powder charge is referred to as "ejecta". The ejecta total weight affects free recoil.

For fellow shooting nerds, here's a simple article from Outdoor Life concerning shotgun recoil. The concept is the same for rifles.

Shotgun Recoil: Here's What Hunters and Shooters Need to Know

There are two different types of recoil that are important to shotgun shooters: free and felt recoil. Understanding both will help accuracy.

www.outdoorlife.com

“There are two kinds of recoil shotgunners care about. The first is the free recoil that the mathematic formula gives us. The second is the perceived recoil (aka felt recoil), which is the cause of a swelled cheek and sore shoulder (i.e. the recoil you feel). They are different, but free recoil is directly related to perceived recoil.

While there are several free recoil formulas, I like the one from powder maker Hodgdon. It includes the weight of the gun, the weight of the ejecta (shot, wad, and powder), and the speed of the ejecta.

The formula for recoil energy in ft./lbs. is:
(Bw Mv + 4,700 Pw)2 / (64.348 Gw) where:
Bw = weight of the ejecta (shot and wad) in pounds;
Mv = muzzle velocity in feet per second;
Pw = powder weight in pounds; and Gw = the weight of the gun in pounds.”

The above excerpt from Outdoor Life clearly identifies defines the “ejecta” as everything that leaves a gun’s chamber to include the weight of the powder. A heavier powder charge does increase recoil. That’s why if all else is equal, a 416 Rigby produces more recoil than does a 416 Remington. The Rigby was designed to operate with low pressure in the era of Cordite gunpowder which was very temperature sensitive. Even on the hottest day in Africa, where the pressure produced in an old 416 Rigby far exceeded its mean working pressure (47000 psi), the bolt will still function for a second shot! My SWAG (sophisticated wild ass guess) is a Rigby's bolt would open with 65,000 psi, if not a little more.

For comparison, here is a recoil calculator for shotguns: http://www.omahamarian.org/trap/shotshellenergy.html
It calculated for a heavy 12 ga magnum 1.5 oz load at 1350 fps muzzle velocity at 44 lbs free recoil:

View attachment 623262

One can add ejecta weight or increase velocity but a 12 ga, 8 lb. shotgun will not produce the same level or recoil as a 10.5 lb. 458 Winchester! But firing three rounds quickly from this shotgun will definitely get one's attention!

Bonus: Here's a good article on the 416 Rigby;

An Official Journal Of The NRA | The .416 Rigby: History and Performance

Designed from the ground up by William Rigby of the British firm John Rigby & Co., the .416 Rigby matched the power of the .404 Jeffery while also being compatible with bolt-action feed systems.

www.americanrifleman.org

Thanks Mark!!! I knew she was kicking me hard lol

 

[cmk]

I don't know about "many" reasons for 460 Wby's lack of acceptance. I'd guess there's one reason: what is the purpose of a 500 gr bullet scooting along at 2500 fps, and the recoil that goes with?

I mean sure, it still has more energy at 300 yards than my pokey little 404J loads have at 100, but is shooting at DG from 300 yards a thing?

<snip>

Old Roy created a solution to a problem that never existed.

Well, I've wondered about that a little...

I haven't shot either of the following, but they all seem pretty similar in calibre, bullet weights, velocities and thus, energy and recoil (only looked at numbers from Wikipedia). How come that the first one of these is .... frowned upon a little, but the others not so much?

.460 Wby
.500 Jeffery
.450 Rigby
.505 Gibbs

The 500 Jeff especially, is quite close to the Wby, and it's not like the 450 Rigby is an 'old classic'. I suspect that any of these would work in a bolt action 'stopping rifle', but I don't think I've ever read about a stopper in .460 Wby. Is that the Weatherby rifles themselves (or their users) are less appealing?

 

[sgt_zim]

Well, I've wondered about that a little...

I haven't shot either of the following, but they all seem pretty similar in calibre, bullet weights, velocities and thus, energy and recoil (only looked at numbers from Wikipedia). How come that the first one of these is .... frowned upon a little, but the others not so much?

.460 Wby
.500 Jeffery
.450 Rigby
.505 Gibbs

The 500 Jeff especially, is quite close to the Wby, and it's not like the 450 Rigby is an 'old classic'. I suspect that any of these would work in a bolt action 'stopping rifle', but I don't think I've ever read about a stopper in .460 Wby. Is that the Weatherby rifles themselves (or their users) are less appealing?

Good point on the 450 Rigby.

I'd guess the draw with the pair of 50 cals is 600 gr bullets.

Haven't seen a new Wby rifle in years. I worked in a gun shop in Huntington (Long Island) years ago (89 - 91), we had a few come through. I thought the OEM furniture was unattractive.

Had a really wealthy lawyer as a regular customer, had booked an elk hunt in Vermejo Park, and got it in his mind he needed a 340 Wby. But he couldn't shoot it. He developed really bad flinch, missed a couple GIANT bulls from pretty close range. He'd have been better off with an A-Bolt in 30-06 or 300 WM.