recoil v accuracy

[WildRose]

It definately ain't going to where it had the other one put on thats for sure Unfortunatly because of my location I am kind of limited as to where I can take it. I am going to ask the gun dealer that I have ordered my 110ba from as to who he would send it to if it were his. Got a feeling I'm going to be shipping it out. Any suggestions for the central interior of B.C. welcome. (sorry to the OP about the hijacking)

Yes invite me up one of these years to chase some of your wonderful big critters! gun)

Sorry I have zero connections north of the border.

Found this cutout of the Knoxx Spec Ops Shotgun stock. They make a rifle stock of similar design that is advertised to reduce recoil in two planes but in reality works in three planes. The first two are the spring buffers shown, the third is in the design of the forearm which can flex to absorb some of the shock as well when fired off a bipod particularly.

There are others that get much more high tech and some much lower tech that simply work by building in flex in the stock.

 

[bman73]

Yes invite me up one of these years to chase some of your wonderful big critters! gun)

Sorry I have zero connections north of the border.

As long as you promise to share some shooting tips with me your more than welcome to come up anytime. Pick your poison, spring bear hunt or pretty much anything else in the fall. Not huge moose like Alaska around here but the ones we have ain't nothing to turn down and taste fantastic as well.

 

[rscott5028]

Opinions are like _-holes. ..everybody has one.

FWIW, here's my opinion...

Rearward motion of the rifle begins at ignition. But all by itself, it's not especially detrimental to accuracy/precision. The effects can nearly be cancelled completely with a good tracking benchrest rifle that's simply fired by touching the trigger.

Dry firing most hunting rifles shows us that the shooter, trigger, and spring loaded hammer also induce motion of the rifle during the ignition process.

Lock time and the unintentional effects of the shooter have a significant effect. ...especially with an inexperienced (or out of practice) shooter that flinches due to the anticipated recoil and noise.

Gases exiting the barrel cause a significant portion of felt recoil.

Muzzle breaks tame recoil and may help shooters avoid flinching. Even so, they aren't required for very accurate benchrest rifles that track properly largely due to the fact that the jet propulsion aspect of recoil occurs after the bullet has left the muzzle. And with a decent crown, the gases don't disturb the bullet too much as it exits.

Even while the rifle is recoiling due to good old Newton, vibrations running down the barrel may also affect accuracy. ...although barrels that flex and vibrate consistently with a well tuned load may still be very accurate.

A well designed shooting system and good technique go a long ways towards offsetting the negative effects of all of the above.

Recoil isn't something to fixate on. Rather it should be ignored altogether.

-- richard

 

[WildRose]

As long as you promise to share some shooting tips with me your more than welcome to come up anytime. Pick your poison, spring bear hunt or pretty much anything else in the fall. Not huge moose like Alaska around here but the ones we have ain't nothing to turn down and taste fantastic as well.

Easy, throw all the physics and math out and I'll teach you about the "art" of shooting.

For one thing when you aren't set up on a bench with all the right gear it's almost impossible to ever get completely steady.

The way around that is to not try.

Get on target after you HAVE done the math and done your doping and get a rythym goign with your breathing, heart rate, wind gusts, and slowly time your squeeze for that perfect moment when the cross hairs are in just the right place such that the release is at that exact moment. I also personally try to be slowly leaning into the sticks, tree or bipod at the same time focusing whatever extraneous movement there is directly toward the target.

I find that with most shooters on breathing targets, trying to focus too hard on getting absolutely steady before the shot tends to make them a little shaky and nervous leading up to "shooter error".

I also have found that with the advancements in technology much of the art is being lost resulting in a lot of aggravated shootes when it doesn't come together the same in the field as it does on paper.

That won't win you any bench rest championships but it will put a hell of a lot of dead meat on the ground with practice.

You may have missed this edit of the earlier post.

http://www.botachtactical.com/knspadst.html

Found this cutout of the Knoxx Spec Ops Shotgun stock. They make a rifle stock of similar design that is advertised to reduce recoil in two planes but in reality works in three planes. The first two are the spring buffers shown, the third is in the design of the forearm which can flex to absorb some of the shock as well when fired off a bipod particularly.

There are others that get much more high tech and some much lower tech that simply work by building in flex in the stock.

http://www.botachtactical.com/knspadst.html

I have shot their rifle stock and it's pretty damned neat.

 

[WildRose]

Opinions are like _-holes. ..everybody has one.

FWIW, here's my opinion...

Rearward motion of the rifle begins at ignition. But all by itself, it's not especially detrimental to accuracy/precision. The effects can nearly be cancelled completely with a good tracking benchrest rifle that's simply fired by touching the trigger.

Dry firing most hunting rifles shows us that the shooter, trigger, and spring loaded hammer also induce motion of the rifle during the ignition process.

Lock time and the unintentional effects of the shooter have a significant effect. ...especially with an inexperienced (or out of practice) shooter that flinches due to the anticipated recoil and noise.

Gases exiting the barrel cause a significant portion of felt recoil.

Muzzle breaks tame recoil and may help shooters avoid flinching. Even so, they aren't required for very accurate benchrest rifles that track properly largely due to the fact that the jet propulsion aspect of recoil occurs after the bullet has left the muzzle. And with a decent crown, the gases don't disturb the bullet too much as it exits.

Even while the rifle is recoiling due to good old Newton, vibrations running down the barrel may also affect accuracy. ...although barrels that flex and vibrate consistently with a well tuned load may still be very accurate.

A well designed shooting system and good technique go a long ways towards offsetting the negative effects of all of the above.

Recoil isn't something to fixate on. Rather it should be ignored altogether.

-- richard

Emphasis mine.

Yep, that's why we do what we can to control it before we get into the field it so you don't end up dreading what happens when you pull the trigger.

 

[justgoto]

...You have spent 11 pages in this thread repeating your statements and ignoring contributions by others. When asked what it would take to make you agree with someone else's viewpoint (since everyone, including YOU could be wrong), there is apparently no experiment, dataset or fact that will make you change your mind.

Given that mindset (nothing left to learn from any of us), you have made my ignore list.

Happy trolling...

I have seen no such argument from WildRose; I see very much the opposite. I see no one addressing 50% of their argument; whereas WildRose has addressed every point; some of which is scientific experimentation that remains unchallenged. I see instead of debate, challenges in WildRose's use of grammar, their integrity, their intelligence. I see some playing nice; others, not so much.

 

[Buffalobob]

I may not be eloquent in geek speak but my numbers are correct, and you have not presented any contrary evidence which would dispute them

The experiemtal evidence I provided supports my contentions 100% and you can provide nothing that shows otherwise.

Now stuff the snark and act like an adult.

The only thing you have proven is that you are a BS artist who likes to use words you don't know the meaning of and make up preposterous statements that negate the known laws of physics.

 

[westcliffe01]

Did you read the FEA analysis and shooting test I posted on VarmintAl's site ? It was proven both practically and analytically that by changing the powder load a tiny bit, or moving the tuning weight less than 1/2" forward or backwards that the muzzle could be pointing upward, straight or downward with no other contributing factors.

The only part of recoil which has any significance to point of impact is the part which occurs before the bullet leaves the barrel. What happens after the bullet leaves the barrel only serves to scare the shooter.

If one can't or won't read, can't comprehend the subject matter and can't or won't ask questions about things one does not understand, one will remain forever ignorant. Barrel Tuner Analysis -- FEA Dynamic Analysis of Esten's Rifle with/without a Tuner.

I have seen no such argument from WildRose; I see very much the opposite. I see no one addressing 50% of their argument; whereas WildRose has addressed every point; some of which is scientific experimentation that remains unchallenged. I see instead of debate, challenges in WildRose's use of grammar, their integrity, their intelligence. I see some playing nice; others, not so much.

 

[davkrat]

I did not read the entire thread as it got old after 3 pages. Did anyone ever mention the shifting of the center of gravity that occurs during recoil. The reason some recoil calculators ask for weight of powder charge as well as bullet. Those two masses shift the center of gravity of the rifle the instant the bullet starts to move causing the rifle to move. I'm no physicist but I have heard that people over emphasize the rocket effect and ignore the shift in the center of gravity.

 

[Buffalobob]

Did anyone ever mention the shifting of the center of gravity that occurs during recoil.
Reply With Quote

Lightwind mentioned it directly during his discussion of conservation of momentum and I mentioned it indirectly by suggesting that using different reference frames would allow a person to see the forces and motion from different perspectives.

 

[westcliffe01]

If we take an obvious candidate for high recoil, the 50bmg, a 750gr bullet is accelerated to 2800fps and has an energy of 13 000 ftlb when it leaves the muzzle. The same amount of energy is transferred to the rifle and shooter, with the only difference being the mass of the rifle and shooter compared to the bullet, as well as the fact that the rifle acts on the shooter over a larger surface area than the bullet does at the target. In most cases, the bullet does not expend all of its energy on the target, in addition to which the bullet has lost considerable energy on the way to the target through aerodynamic drag.

Assuming the rifle weighs 14lb and back calculating from the bullets muzzle energy, it works out that the rifle would recoil at 43fps, which sounds a lot more survivable when meeting a rifle butt, than the bullet at 2800fps.... Taking the average speed of recoil of the rifle to be 43fps and the duration of the flight of the bullet in the barrel to be 2ms (it might be less), the rifle would move back 1", not yet accounting for muzzle blast. if the shooter was holding onto the rifle real tight, like I would and I weigh 225lb, things look a little different. Now the shooter/rifle combined weight is 239lb and the recoil velocity is just over 10fps. In the same 2ms movement of the shooter and rifle would be 1/4" (not taking muzzle blast into account).

Is this kind of recoil going to get your attention ? Hell yes ! Is there a lot of opportunity for the bore to become misaligned with the target (especially if at a range of 1 mile ?) Hell Yes !. I do not know this for a fact, but I am guessing that only the best shots get to be behind a 50 sniper rifle, since I am sure they are not easy to shoot well, are punishing on the body, are big and heavy to lug around and one physically cannot carry much ammo around with you. Devastating in the right hands, but equally useless in the hands of someone who can't handle it.

A lot of the heavy recoiling "big game" rifles were saved by the fact that they were often shot at point blank range, and when shooting one had much more important things to worry about than how much your shoulder was going to hurt from firing. Miss the shot on the charging lion, elephant or buffalo and pretty soon you would be hurting in a lot worse ways ! Probably for the last time too.

I did not read the entire thread as it got old after 3 pages. Did anyone ever mention the shifting of the center of gravity that occurs during recoil. The reason some recoil calculators ask for weight of powder charge as well as bullet. Those two masses shift the center of gravity of the rifle the instant the bullet starts to move causing the rifle to move. I'm no physicist but I have heard that people over emphasize the rocket effect and ignore the shift in the center of gravity.

 

[westcliffe01]

Lets do another one: a 7.62x51 FAL shooting a 160gr match bullet just shy of 2800fps. Rifle weighs 8.75lbs, probably going close to 10lb with a 20rd mag.

Muzzle energy is 2785ftlb The rifle itself will recoil at 23.6 fps and will move 0.35" during the time the bullet is in the barrel (close to 1.2ms for a 21" barrel). Again, with the shooter prone and aligned with the rifle and weighing 225lb, the recoil velocity is 4.87 fps, the rifle and shooter move 0.070" during the 1.2ms that the bullet is in the barrel. Again, I do not have any empirical formulas for the muzzle blast and it affects mainly the shooters nerves as well as the time to get off a second shot.

Finally, lets look at the 5.56 nato: Here the rifle weight is probably 6.5lb. With a 50gr bullet traveling at 3500 fps from a 16" barrel (may be a bit optimistic) the muzzle energy would be 1360ftlb. With the rifle being so light, it would recoil at a velocity of 20.46fps and would move 0.23" during the 1ms that the bullet was in the barrel. With the shooter "attached" weight 225lb, these numbers change to 3.43fps and 0.040" of rifle/shooter movement in 1ms.

Clearly, the perceived recoil of these various scenarios is substantially different and anyone who has shot them would attest to that fact, muzzle brake or not. All are normally fitted with muzzle brakes to begin with, given their use by soldiers in combat, where follow up shots are important. Anyone should be able to guess which will be easier and more accurate to shoot with limited experience: It will undoubtedly be the 5.56. Too bad the bullet runs out of steam before it has gone too far and that you have to shoot the Somali bad guys several times to put them down. Thats the "NFL" (no free lunch) rule coming right back at you. The FAL in 7.62x51 has decidedly more "kick" than the 5.56, and the ammo is bulkier and heavier, but it has double the muzzle energy and will put most bad guys down in 1 shot compared to the 5.56. But it can be mean enough to scare some shooters into flinching etc, particularly when it has a short barrel, folding stock etc.

Finally, most of us will never graduate to the 50bmg level. The rifle is too punishing both physically, acoustically, mechanically (carrying it and the ammo) and most of us would shoot it real lousy too, compared to a softer shooting rifle.

Yes, recoil has an effect on accuracy. The higher the muzzle energy, the harder it will be to shoot the weapon well. Given that high muzzle energy rounds are intended for either long range shooting or for instant stopping power on dangerous game at close range (2 very different applications) the first will take a great deal of skill to master, whereas the second takes mainly good mental focus and cool nerves.

 

[WildRose]

Lets do another one: a 7.62x51 FAL shooting a 160gr match bullet just shy of 2800fps. Rifle weighs 8.75lbs, probably going close to 10lb with a 20rd mag.

Muzzle energy is 2785ftlb The rifle itself will recoil at 23.6 fps and will move 0.35" during the time the bullet is in the barrel (close to 1.2ms for a 21" barrel). Again, with the shooter prone and aligned with the rifle and weighing 225lb, the recoil velocity is 4.87 fps, the rifle and shooter move 0.070" during the 1.2ms that the bullet is in the barrel. Again, I do not have any empirical formulas for the muzzle blast and it affects mainly the shooters nerves as well as the time to get off a second shot.

Finally, lets look at the 5.56 nato: Here the rifle weight is probably 6.5lb. With a 50gr bullet traveling at 3500 fps from a 16" barrel (may be a bit optimistic) the muzzle energy would be 1360ftlb. With the rifle being so light, it would recoil at a velocity of 20.46fps and would move 0.23" during the 1ms that the bullet was in the barrel. With the shooter "attached" weight 225lb, these numbers change to 3.43fps and 0.040" of rifle/shooter movement in 1ms.

Clearly, the perceived recoil of these various scenarios is substantially different and anyone who has shot them would attest to that fact, muzzle brake or not. All are normally fitted with muzzle brakes to begin with, given their use by soldiers in combat, where follow up shots are important. Anyone should be able to guess which will be easier and more accurate to shoot with limited experience: It will undoubtedly be the 5.56. Too bad the bullet runs out of steam before it has gone too far and that you have to shoot the Somali bad guys several times to put them down. Thats the "NFL" (no free lunch) rule coming right back at you. The FAL in 7.62x51 has decidedly more "kick" than the 5.56, and the ammo is bulkier and heavier, but it has double the muzzle energy and will put most bad guys down in 1 shot compared to the 5.56. But it can be mean enough to scare some shooters into flinching etc, particularly when it has a short barrel, folding stock etc.

Finally, most of us will never graduate to the 50bmg level. The rifle is too punishing both physically, acoustically, mechanically (carrying it and the ammo) and most of us would shoot it real lousy too, compared to a softer shooting rifle.

Yes, recoil has an effect on accuracy. The higher the muzzle energy, the harder it will be to shoot the weapon well. Given that high muzzle energy rounds are intended for either long range shooting or for instant stopping power on dangerous game at close range (2 very different applications) the first will take a great deal of skill to master, whereas the second takes mainly good mental focus and cool nerves.

The longest ever kills with sniper rifles are now exceeding the 1,800-2,500M ranges. Those are with 50bmg and 408 Cheytac.

I have personally shot both at ranges exceeding 1,500m. I have even seen one shooter get five consecutive sub MOA hits on a steel target at 1,800m with the new .375 Cheytac.

If recoil was having a negative impact on accuracy these shots would not be possible.

Other than muzzle brakes these rifles do not have any built in recoil dampening and both have recoil forces exceeding 70lbs.

On average we are talking about bullets that remain in the rifle no mor than .002 seconds vs recoil velocity of less than 20fps.

20fps x .002=.04 ft of possible movement during that time with most of that force being directed in linear fashion straight back towards the shooter.

This does not provide an opportunity for the recoild to be having any significant effect on accuracy.

This is compared to the average sporting rifle in .223-30-06 which will have recoil forces of sub 14lbs.

Recoil itself is not affecting accuracy, our reactions/anticipation of recoil is what affects accuracy.

 

[WildRose]

Lets do another one: a 7.62x51 FAL shooting a 160gr match bullet just shy of 2800fps. Rifle weighs 8.75lbs, probably going close to 10lb with a 20rd mag.

Muzzle energy is 2785ftlb The rifle itself will recoil at 23.6 fps and will move 0.35" during the time the bullet is in the barrel (close to 1.2ms for a 21" barrel). Again, with the shooter prone and aligned with the rifle and weighing 225lb, the recoil velocity is 4.87 fps, the rifle and shooter move 0.070" during the 1.2ms that the bullet is in the barrel. Again, I do not have any empirical formulas for the muzzle blast and it affects mainly the shooters nerves as well as the time to get off a second shot.

Finally, lets look at the 5.56 nato: Here the rifle weight is probably 6.5lb. With a 50gr bullet traveling at 3500 fps from a 16" barrel (may be a bit optimistic) the muzzle energy would be 1360ftlb. With the rifle being so light, it would recoil at a velocity of 20.46fps and would move 0.23" during the 1ms that the bullet was in the barrel. With the shooter "attached" weight 225lb, these numbers change to 3.43fps and 0.040" of rifle/shooter movement in 1ms.

Clearly, the perceived recoil of these various scenarios is substantially different and anyone who has shot them would attest to that fact, muzzle brake or not. All are normally fitted with muzzle brakes to begin with, given their use by soldiers in combat, where follow up shots are important. Anyone should be able to guess which will be easier and more accurate to shoot with limited experience: It will undoubtedly be the 5.56. Too bad the bullet runs out of steam before it has gone too far and that you have to shoot the Somali bad guys several times to put them down. Thats the "NFL" (no free lunch) rule coming right back at you. The FAL in 7.62x51 has decidedly more "kick" than the 5.56, and the ammo is bulkier and heavier, but it has double the muzzle energy and will put most bad guys down in 1 shot compared to the 5.56. But it can be mean enough to scare some shooters into flinching etc, particularly when it has a short barrel, folding stock etc.

Finally, most of us will never graduate to the 50bmg level. The rifle is too punishing both physically, acoustically, mechanically (carrying it and the ammo) and most of us would shoot it real lousy too, compared to a softer shooting rifle.

Yes, recoil has an effect on accuracy. The higher the muzzle energy, the harder it will be to shoot the weapon well. Given that high muzzle energy rounds are intended for either long range shooting or for instant stopping power on dangerous game at close range (2 very different applications) the first will take a great deal of skill to master, whereas the second takes mainly good mental focus and cool nerves.

Your figures for the .308 are way off from Chuck Hawk's table which puts recoil velocity at just 12.5fps and You fail to account for the mass of the shooter which also dramatically slows the recoil.

Further once and again. The vast majority of that force is being transferred in a stright line from your shoulder through the end of the barrel making that force move the rifle away from the target lengthening your range by about .004" and not affecting windage and elevation to any significant degree.