RECOIL VERSUS POI

[kuduman49]

First time posting a question . In very simple terms, does the recoil movement of the rifle (if any ) during the time the bullet is traveling in the barrel, have an effect on POI ?? I know about Newton's law of physic about equal and opposite reaction which would pertain to the time the bullet is in the barrel and also realize that the majority of recoil takes place after the bullet has left the barrel. If the rifle does move during the time the bullet is traveling in the barrel, then do we as the shooter compensate for that movement to keep our POI the same ? Food for thought and many thanks for your time in considering your answers.

 

[Immike]

Absolutely, that's a big part of shooting is your gun handling skills. Your influence on the weapon is very important.

 

[bheadboy]

right on,
shoulder pressure, cheek, trigger hand grip, foreend pressure, bag hardness, body position all play into the way the rifle recoils in that time, if they ae not consistant and in a degree the rifle likes, you are in trouble

technique is the term!!!
Bob

 

[Erik Cortina]

Read my signature.

 

[bheadboy]

Erik, i love it
Bob

 

[Erik Cortina]

I came up with it arguing with a friend that said he was going to tune his gun for F-Class to shoot 2.5" vertical, which in turn, would give him a bigger target because a circle is wider in the center. After going back and forth for a few minutes, I asked him, "how do you know your gun is not already shooting 2.5" vertical?", and he said, "Because I have never shot 2.5" vertical before", and I said "there is your problem!"

Then he argued that he could hold 2.5" vertical, and I asked "how do you know if you have never done it?" Anyway, I don't know if I ever convinced him, but the 2.5" vertical never happened, but I'm sure he is still blaming it on the gun. ;D

 

[bheadboy]

simular experience, some years ago, a friend and avid hunter complained his rem 700 custom shop 270 would not shoot under 7/8,

we talked, he blamed the gun wanted to work on it , we went to the range and he shot it as i watched, it went 1", (by the way he is a lefty, not the problem) i asked to let me shot the rifle -- it measured .550

last argument about the gun we had.

Bob

 

[ScottMcc]

And how long the bullet is in the barrel affects poi too. Heavier, slower bullets give the muzzle more time to climb during the shot, raising poi.

 

[BoydAllen]

Stocks generally have an angled toe line (the bottom of the butt), with the result that when they are shot using front and rear bags, the back of the rifle drops as the rifle recoils. This makes consistency of hold important. If your rife recoils farther on one shot than another in the group, before the bullet leaves the barrel, that means that the barrel will be pointing to different placed for each shot.

A friend who has a custom rifle based on an old Martini Cadet action, took my advice and held the rifle more securely back into his shoulder than he had been, and cut his vertical in half. The old Martini stocks have a lot of toe angle.

This is one of the reasons that thousand yard bench rifles generally use flat toe angles. It reduces the effects of bag friction and hold variability.

I have found it to be true that many shooters think that they will get their best results, shooting from the bench, with as light a hold as they can manage, when in fact, using more hold, with consistency, will generally improve their results, unless they are shooting a rifle and bags that were designed for a light or no hold.

 

[broncman]

We just got a new highspeed video camera at work. Part of my perks is getting to play with it. When I get a free weekend I am going to do some research...

It will shoot almost 600 frames per second so I should get some decent footage. I want to see how much whip is in the barrel and few other things.

If 600 frames per second will catch the bullet exit then that will be awesome!

 

[CaptainMal]

We bed barrels and stocks to keep things uniform during the shot. Then you have to "bed" the rifle so it's movement is always the same. Even from a benchrest, the amount of friction on the recoil slide, if varied, WILL affect both impact and accuracy.

Now if we could "bed" ourselves???

 

[MrMajestic]

This is very pronounced in Handgun shooting!

 

[amlevin]

We bed barrels and stocks to keep things uniform during the shot. Then you have to "bed" the rifle so it's movement is always the same. Even from a benchrest, the amount of friction on the recoil slide, if varied, WILL affect both impact and accuracy.

Now if we could "bed" ourselves???

Either that or just buy a Rail Gun.

 

[GrocMax]

I'm not a competitive shooter by any means, but noticed my POI goes up about an inch at 100 yds typical PD type rifle off bags on a hard shoulder hold vs. a light one, and just need to make sure technique is consistent during load dev. or I get really bad data and make bad decisions. Vertical POI changes between load dev. and field use (altitude, technique, etc. ) can be compensated for easily, bad loads that throw all over can't. On that note also found making load decisions on 3 and 5 shot groups are far inferior to a larger statistical sample like 10, spread shooter error over a larger sample and get better load data. Been more than one 3 or 5 shot group looked great until I shot 20 of the same.

 

[amlevin]

I'm not a competitive shooter by any means, but noticed my POI goes up about an inch at 100 yds typical PD type rifle off bags on a hard shoulder hold vs. a light one, and just need to make sure technique is consistent during load dev. or I get really bad data and make bad decisions. Vertical POI changes between load dev. and field use (altitude, technique, etc. ) can be compensated for easily, bad loads that throw all over can't. On that note also found making load decisions on 3 and 5 shot groups are far inferior to a larger statistical sample like 10, spread shooter error over a larger sample and get better load data. Been more than one 3 or 5 shot group looked great until I shot 20 of the same.

It's my belief that unless your rifle is designed to be fired using the "free recoil" method then the hard shoulder hold/cheek weld method will yield best results once you master it.

It's important to make sure that what you're doing is the SAME with every shot. Same cheek weld, same pressure into the shoulder, same position of the other shoulder, same grip, and on, and on.

Take a look at most Bench Rest stocks and note that they're designed with wider, flat, fore ends, flat bottomed stocks, and the bags are waxed so the rifle will slide freely without disturbing the supports. In many cases, once one of these rifles is fired, when the shooter returns it to the original position, the crosshairs are right back on the point of aim (or darn close).

When you can do that with a tight shoulder hold, you've now mastered it.

In the beginning, one just about needs a checklist to make sure that they're setting up for the shot the same way each time. In time it just becomes natural.

 

[BoydAllen]

While we are on shooting technique, let me put in a word or two for correct follow through and trigger pull. When shooting from a support, pressure should be gradually increased on the trigger until the rifle fires. The way that I generally explain this is to someone that I am coaching is that it should surprise you as to when it goes off, rather than saying to yourself I want it to fire right now. The other common fault is a lack of follow through. I am always amazed at how many shooters pull their heads up and look down range, just after the rifle fires, as is they could see the bullet hole at 100 yards or more. By combining the previous poster's advice on consistent body position and hold, with correct hand position so that the trigger is pulled straight back, and pressure added gradually, with correction on follow through, I have been able to cut some shooters group sizes by a considerable amount. I remember one fellow where they went from an inch and a half, to three quarters of an inch, and his mistakes were not easy to spot. He was quite pleased with the difference.

 

[Topstrap]

Love threads like this and some very good comments on it by others that have posted. I'm mainly a LR pistol shooter and recoil and how it's managed or dealt with during each shot is VERY important. I made a short video clip I posted on the Hide for a thread similar to this one and some just can't see the similarities between the two types of guns. It's just more pronounces in a handgun but rifles react the same but to a much lesser degree.

If you do the same thing every time it don't matter how the gun reacts since it'll do the same thing the exact same way if you are doing your part the exact same way. On this clip my son is using one of our early versions with lightweight barrel and no muzzle brake. It looks like it's recoiling wildly but it's extremely accurate and it just shoots better with a light grip it takes a lot of practice to have the same exact grip every time to make it happen. He just put 3 shots a 50 cent piece could cover at 400 yards on a steel plate. The second gun has a heavier barrel and a brake and is much easier to shoot due to less gun movement for nearly everyone that has tried it. An even heavier rear grip model was just finished and we can see hits at all distances due to improved design.

[youtube]http://www.youtube.com/watch?v=Li1tnGRu7Yc[/youtube]

Bigger caliber guns aren't necessarily less accurate but just a bit harder for the less experienced shooter to handle due to gun movement. Very interesting topic and one we've had to pay a lot of attention to. Different shooting disciplines sometimes need different techniques, off hand shooters usually like to know the exact moment it's going to go off to coincide with the sights being in the proper spot on the target, for us and our steel plates either off a bench or prone I like the shot to be a surprise.

Those pictures with the high speed camera will be pretty cool, slow motion videos I've seen on YouTube or how a gun and even the scope reacts are pretty surprising and a real eye opener to someone that has never seen it.

Topstrap

 

[BoydAllen]

In case anyone missed them, there are a couple of links to videos at the bottom of his reply. Thanks for putting them up. We should all be so lucky as to have such a place to shoot. Good shooting

Boyd

 

[37Lincoln1]

Holy Smokes!

 

[timeout]

Little short on time right now, so only watched one of the videos. That is some shooting and with a 3-12 scope!