effects of shooting aids on POI?

[Koda94]

I'm not confident there is an answer to this but decided to ask anyways....

All other things being equal, is there any difference in point of impact (POI) between shooting from a vise like a led sled vs. sandbags? Do the effects of recoil resonate differently between a solid mechanical clamp vs. a softer forgiving sandbag... my guess is yes and would have to affect POI...?

The reason I'm asking is because I've always sighted in with my led sled, and now that I'm zeroed I want to start working towards practical shooting positions and thinking of starting with sandbags, (then prone, then offhand). I was thinking to myself, what if I go back to the range and just use sandbags but my POI is slightly different than from the sled. Should I adjust, or go back to the sled.

 

[JohnKSa]

Anything that affects how the gun moves while the bullet is in the barrel has some effect on where the bullet hits. If it doesn't move very much while the bullet is in the barrel, then the effect may be insignificant. If it moves significantly then it may move the POI a lot.

Ideally, you want to set up your rifle for the way you intend to shoot it. In practice, it may not really make that much difference.

If you want to shoot the rifle from multiple positions, then you'll want to know how (if) it changes for each position and then, if necessary, keep notes so you can make corrections.

 

[Hal]

Should I adjust, or go back to the sle

Adjust. How the gun shoots for you os what matters, not how it shoots in any other situation.

Mounting a gun or even having someone else that you know is a "good shot", can only tell you pretty much what the potential is.
That gives you some sort of base line to fine tune to.

 

[DMK]

Ideally, you want to set up your rifle for the way you intend to shoot it

How the gun shoots for you os what matters, not how it shoots in any other situation.

This is my thinking too.

I always initially zero a gun from a rest, then confirm from offhand positions (standing, kneeling, etc) or even prone, where possible.

Don't forget to consider pressure on the barrel, from the rest, or from a sling if you use one as assist with steadying your shot.

 

[Bart B.]

My experience with 308 Winchester 12 pound target rifles with zeros obtained with the rifle resting on bags atop a bench and shouldered right handed, when shot off-hand or slung up in prone zeroes are 1.5 MOA left.

 

[std7mag]

If you do some searching on here, you'll find a lot of issues related to shooting with a sled.
I won't use one for those reasons. Also i just never felt "natural" shooting with one.

I use a front rest and rear bag for my competitions off the bench. Lately been working with same setup prone.
I also use front and rear bag, and bipod & rear bag.

I also practice alot using different positions, and standing/kneeling using one of the posts for a rest. Ala simulate behind a tree.

 

[jmr40]

Never used a lead sled, but I've used sandbags, bi-pods, and shooting sticks. If there is any difference in POI it isn't enough for me to notice.

 

[Koda94]

If you do some searching on here, you'll find a lot of issues related to shooting with a sled.
I won't use one for those reasons.

I did a search and couldnt find anything. Can you give a brief reply on the issues with a sled?

 

[Bart B.]

Good question to ask.

The bore axis is the recoil force axis when rifles are fired. With their butt against a right handed shooters right shoulder, the body twists right taking the rifle with it as the bullet goes through the barrel. The barrel also rises in recoil because the rifle center of mass is below the bore/recoil axis.

Several people shooting the same rifle and ammo will each have a different zero on the sight. I've seen a 2 MOA spread.

Lead sleds, accuracy cradles and machine rests are great for testing ammo and rifles for accuracy at short range if they use 3 points of support; 2 round bars in V blocks and a third on another. Good at long range if they let the rifle move in recoil like it does hand held. Not good to get zeros to use in hand held field positions. Like this one used by some national highpower champions:

http://www.flickr.com/photos/12787226@N00/sets/72157594303093714/detail/

If you can call your shots pretty good, you should be able to get a good zero with a decent rifle shooting 3 rounds standing at 100 yards. Without any shots going dead center on a bullseye target.

 

[Koda94]

@Bart B. that's good information, in short then yes it makes a difference

I guess the answer I'm looking for is to zero from the position that's most practical for the application (ie. hunting) and compensate for the rest of the positions if needed.