Recoil and the shooter


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Any  discussion about getting kicked deals with a complicated  subject – a combination of physics, dynamics, psychology, and hot  air. There are two aspects of recoil. One is kinetic energy  developed by the recoiling gun. The other is “kick,”   which is  felt by the shooter’s shoulder. Kinetic energy is measured in  what is called “foot pounds of free recoil.” This is a  comparative measurement and in general is indicative of the  amount of push-back exerted by various firearms. However, it  isn’t the whole story.

When a gun is fired,  the cartridge is ignited and expanding  powder gas pushes against the base of the bullet and starts  moving it through the barrel. An equivalent amount of push  is exerted to the rear against the bolt face, and this  “backthrust” drives the rifle to the rear. If the bullet and gun  weighed the same, the gun would recoil backward as fast as the  bullet went forward. Fortunately, the gun is several hundred  times as heavy as the powder and the bullet.

The  lighter  the gun,  the faster it is pushed  back,  the  heavier the gun the slower the push. Firing the same cartridge, a  4.5kg gun has half the recoil of a 2.25kg gun. All things being  equal, the ejecta (bullet or shot charge plus powder charge) the  greater the recoil. For example, the 500gn bullet out of the  barrel of an old Sharps rifle at 1300fps would give much less  recoil than a bullet of the same weight fired from a .458  Winchester Magnum at twice the speed.

Recoil has been measured in various ways. Not so long ago it  was done scientifically by firing guns on a pendulum and  calculating the recoil velocity by measuring the length of the  arc of the swing, by using recoil dynamometers, and other  instruments. Today, things are much easier. Recoil is simply  calculated with a computer using a ballistics programme and  feeding in  relevant data – bullet weight and the weight of the  powder charge, the weight of the firearm and the muzzle velocity.

Most  of us don’t have any idea what the recoil of  a  given  cartridge fired in a certain gun is – and we don’t much care.  What counts is whether the recoil is too heavy and unpleasant  enough to upset our shooting.
Most  people don’t notice the recoil when firing a .22 rimfire  rifle. This is hardly surprising. The little .22 Long Rifle high-  velocity cartridge when shot from a 2.27kg rifle recoils with a  speed of 1.76 fps and turns up about 114 grams of free recoil.  Nor are the .22 centrefires hard enough on the shoulder to cause  anyone to  flinch. Take the .222 Remington as an example, it has  5.66 fps recoil velocity when fired from a 3.175kg rifle and a  mild 3.48 ft/lb of recoil.

When  our service rifle was the 7.62x51mm  NATO,  the  army  experienced considerable difficulty teaching recruits, most of  whom had never fired a gun of any kind in their lives, to shoot.  The F.N 7.62 rifle weighed around 4kgs. With the military M80  load of a 150gn FMJ BT bullet at 2750fp s the recoil velocity is  9.9 fps and the recoil energy is 13.7 ft/lb. When the army  cashiered the 7.62mm in favour of the 5.56x45mm NATO the M855  military load firing a 62gn bullet at 3100fps was much easier for  recruits to shoot with – recoil velocity was 5.2 fps and recoil  energy a mere 3.4 ft/lb. Marksmanship improved out of sight with the milder kicking 5.56mm.

Most  sport shooters  are familiar with the  .308 Winchester  which is the civilian version of the 7.62mm NATO, and most of us  have shot .308 rifles. Many beginners as well as less experienced  shooters consider the .308 to be a frighteningly powerful rifle –  a real going hell for leather round. Quite a few hunters weren’t  too proud to admit that the .308 kicked too much for them, which  may be the reason why the .223 Remington, the sporting version of  the 5.56x45mm NATO, has become so popular in recent times, at  least with those who shoot infrequently. But big game calibres   and the modern magnums kick a lot more.

Even  guys  who  shoot a lot  appreciate  a  cartridge  that  isn’t likely to dislocate their shoulder. The  .270 Winchester  with  130gn bullet leaving the muzzle of an 3.6kg rifle at  3140fps has a recoil of 16.88 ft/lb. The .30-30 with a 170gn  bullet at 2200fps gives a  recoil of 12.36 ft/lb when fired in a  3.6kg rifle. One reason for the popularity of the  .243  Winchester and 6mm Remington is that they have mild recoil and  are pleasant to shoot. Even in 3.175kg rifles, they turn up less  than 12 ft/lb of recoil.

The .300 WSM and .300 Win.  Mag. are fairly popular with deer  hunters, but many who shoot them  cannot handle their sharp  recoil and miss a good many shots. The late Les Bowman who for  years was an outfitter in Wyoming told me that he’d seen more  game wounded with .300 magnums than with any other calibre simply  because hunters who used them were afraid of their heavy recoil.  As I may have mentioned a time or two before, the only bullets  that count are those that land in the right place.

Everyone  has  his own level of recoil tolerance.  I am  not  in the least uncomfortable when I shoot rifles in the .270-.30-06  class from a benchrest where one absorbs the maximum amount of  recoil. And I have no trouble shooting my .338 or .375 in the  field, but shot prone or from a benchrest they quickly become  hard work.
My working load in my .338 Win.  Mag. drives the 225gn bullet  at 2885fps.  The Whitworth Mauser rfile weighs 4kgs and has  a  recoil velocity of 15.3 fps and 32.8 ft/lb of recoil. The .375  H&H magnum firing a 270gn bullet from a 3.8kg rifle comes back at  the rate of 19.11 fps and belts the shoulder with 45 ft/lb of  recoil. The .458 Win. Mag. uses 69gn of powder to push a 510gn  soft-point out at 2125 fps. Recoil velocity of a 4.3kg rifle is   20.16 ft/lb and recoil energy is 46 ft/lb.

One  of  the hardest kicking and most powerful rifles   I’ve  fired is the .460 Weatherby Magnum which pushes a 500gn bullet at  2600 fps and produces a whopping 7507 ft/lb of energy. Recoil  velocity is 27 fps and recoil energy  102 ft/lb. I can stand  shooting this hand cannon offhand once or twice, but shot in cold  blood it really shakes me up. Other calibres I’ve found  unpleasant are the  .378 and  .416 Weatherby Magnums. For anyone  looking for  more energy, the .475 A&M Magnum and some of the A-  Square cartridges develop 10,000 ft/lb of muzzle energy!  Those  who shoot these big guns are looked upon as brave and sturdy  chaps.

Some bravos brag they are not bothered by heavy recoil. They  must be a lot tougher than I am!  Once I knew a guy who made a  pastime out of shooting a ponderous .577 Nitro Express  and all  manner of big-bore and Super Magnum rifles. He claimed that the  750gn bullet moving at a leisurely 2050fps and producing about 75  or 80 ft/lb of recoil didn’t bother him in the least. Alas, after  a few years the whiplash effect of firing so many big guns  wrecked his neck and spine and he had to give up shooting  altogether. The effect of firing a rifle of heavy recoil is like  getting slugged on the jaw by a heavyweight boxer. If that’s fun,  you can have it!

Nor do shotgunners get off scotfree.  A trapshooter can fire  with no ill effects or discomfort 150 to 200 trap loads giving 20  ft/lb in an afternoon. But suppose he touches off that many  rounds of heavy duckloads with 3-3/4 drams of powder and 36 grams  of shot? The recoil is a bit over 30 ft/lb and he would be  flinching and nursing a headache long before he’d fired 150  shots.

Years  ago a Du Pont ballistician wrote that recoil over 28  ft/lb or recoil velocity over 21 fps could not long be endured. A  theory I heartily agree with. A rifle of the power of a .243, 6mm  or  .257 Roberts can be made as light as 3kgs and not punish the  shooter. A .270 or .30-06 should not weigh less than 3.6kg, and a  rifle in the class of the .270 WSM or 7mm Rem. Mag. shouldn’t  weigh less than 3.8kg. But I don’t think any .300 magnum should  weight less than 4kg. If they are lighter they kick like mules.  Magnum rifles should all be fitted with a good recoil pad like  the Limbsaver.

My .375 H&H Model 70 fitted with a 2.5-8×40 Zeiss Conquest  scope weighs all-up 4.5kg. Recoil is not bad largely thanks to  the straight stock. I do not think the .375 or .338 should weigh  less. Cannons like the .458 and .460 Weatherby should weigh 6kg  or more. My .416 Taylor weighed 4kg  and I wouldn’t have wanted  it any lighter, even though it had an Answer muzzle brake and pad  fitted which made it kick like a .30-06.
In these days of super magnum rifles and magnum shotshells  a great many people are overgunned because they can’t handle the  recoil. We all do our best shooting with guns we enjoy to shoot.  No one does his best shooting with a gun he is scared of!

The article was first published in Sporting Shooter, October 2011


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Nick Harvey

Nick Harvey is one of the world's most experienced and knowledgeable gun writers, a true legend of the business. He has been writing about firearms and hunting for more than 65 years, has published many books and uncounted articles, and has travelled the world to hunt and shoot. His reloading manuals are highly sought after, and his knowledge of the subject is unmatched. He has been Sporting Shooter's Gun Editor for longer than anyone can remember. Nick lives in rural NSW, Australia.

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