POI Change between Prone and Bench

[ShtrRdy]

I took my target/varmint AR-15 out to do a little shooting at the range. I have a point of impact change between shooting off a bench with a short bipod and rear bag, compared to shooting prone with a little taller bipod and rear bag. The hits from the bench are about 1" higher. What is the reason for this difference? Thanks - Todd

 

[RobertB]

Are the prone shots off of dirt? Or a different material than the bench? It could be your position changing form differnt positions or it could be how the gun reacts to a differnent surface.

Good luck

 

[BC 6.8]

Do you have a free float handguard? If not you could be putting more pressure on the forend when shooting off the bench.

 

[fmsniper]

bench recoil is normally straight back
bipod prone (during recoil) tends to force the barrel up causing a shift of poi high
unless you are running a atlas or versa pod with front and back latitude
if you are using a harris bipod with no tilt you tend to see this

Since your bipod is taller(is it flexing causing the barrel to drop) during recoil?

normally the situation is reverse ( bipod prone is higher)

 

[shooter6.5]

Willing to bet it is the position of your cheek on the stock!
Changes from prone to bench!

 

[fmsniper]

when I teach my long range shooting class, I have my students check zero at the bench then shoot from the prone, and almost all of them have this issue with none tilting bipods.

it is what it is.

 

[Temp9]

Not sure how many times I've posted LL's video, now, but here it is again:

Shooting off a Bench - YouTube

 

[ShtrRdy]

Thanks for the tips and info! I am using Harris bipods. The low one, (a BR model), does not swivel. The next length model, (I don't recall the name), does have the swivel top.

The gun has a free float handguard.

Shooting off a concrete bench covered with indoor/outdoor carpet. When shooting Prone, the bipod feet were on a Midway shooting mat - about 1/2" thick.

The video says I need to lean more into the rifle. I'll try that next time. I was pulling the stock into my shoulder pocket and leaning forward a little, but maybe I need to lean into it more.

I don't seem to have this problem with my bolt gun in 260.

 

[Smokerroller]

I believe it is the difference in how the rifle recoils in your shoulder that would cause the difference in the POI. From the bench the rifle has more leverage recoiling against your shoulder causing more movement rearward with your body. From the prone the rifle cant push you as far as it can from the bench where the distance from your shoulder to where your are anchored to your seat has a radius effect. Similar to how two different shooters can have different POIs with the same rifle because of their different body weight. This is more pronounced as the weight difference increases, of course.

 

[Rob01]

Just had this same question over at another forum. I told the shooter his body position was off and someone else said to check parallax. He did both and found no more shift from bench to prone. There should be no shift if you are driving the rifle properly. You don't need alot of force or "loading" to do this. In prone get directly behind the rifle, use your good fundementals and use good follow through making sure to watch the trigger finger doesn't pop off the trigger. Pull the trigger to the rear and as the shot breaks hold it back and just let it go far enough to hear the trigger reset click.