Advanced Marksmanship Reticle shifting straight up under recoil today.

[TheGerman]

What causes this?

Was at one spot and shot 30 rounds, no issues. Moved to another area that was slightly uneven but whatever, and noticed right off that the recoil was different in that basically every time I fired, the reticle would go 2MIL or so straight up above the target. Occasionally it would go up and slightly left as well.

Didn't change a thing between spot 1 and spot 2 other than spot 2 was very rocky and the only thing I can think of is I may have been laying to where my legs were a bit canted to my left due to the weird terrain and rocks I was basically laying on.

What causes the reticle to go up, up and slightly left? Rear bag? Stock too high/low in shoulder? Couldn't figure out what was different.

 

[CrazyHorse_mk14]

I would guess that it’s the stock too low in arm causing the muzzle to rise. Right or left is usually not being behind the gun. I suck at prone shooting tho, I haven’t practiced it a lot since my method of shooting is usually putting meat in the fridge and laying down in the woods is a good way to get ticks on your balls. I’m sure a more edumacated answer will come along shortly

 

[demolitionman]

My bipod will hop up significantly when shooting off hard surfaces that prevent me from effectively loading the bipod. Happens a little off of gravel too but on sand soft dirt or grass i have zero rifle hop or reticle jump....fwiw. to me it sounds like your not able to get square behind the rifle and absorb the recoil in a straight line therefore the gun is just following its natural path of recoil.

 

[Apnea]

Had this happen a couple days ago. I was shooting on a slightly downward sloping surface and having some trouble with loading the bipod (Atlas legs rolling), so I think I was modifying my position without realizing it. I can only explain the shift by the rear of the rifle going down. I'm wondering if my rear bag control was not so good because I was distracted with all of the other positional stuff. I do remember having to fuss a lot with the bag to get the point of aim that I wanted.

Im going to try that spot again and see if I can figure it out. Bipod legs forward at 45 degrees might have been worth a try but I didn't think of it until after.

 

[TheGerman]

Was thinking its the rear bag as well, or at least part of it. I was fighting with it a bit; either was too low and didn't hold the butt up enough or was too damn high.

I've also been messing with my shoulder/rifle stock butt position lately as I was actually able to fairly repeatedly pull off perfect recoil (line up on target, fire, still on almost exact spot on target again). Now that I've been dicking around with it, its almost another variable as now everytime its not perfect I'm thinking to myself that the butt is too high/too low.

 

[_Windrider_]

A lot of it is body position. If you aren’t straight behind the rifle recoil takes a different path because you have introduced an angle into the system

 

[TheGerman]

A lot of it is body position. If you aren’t straight behind the rifle recoil takes a different path because you have introduced an angle into the system

Yes we know, Yoda

But what the hell made it change between 2 different spots like that? At some point it drove me nuts like i had gone back in time or something.

Let me ask this. If the rear bag was too low underneath the stock, as in, it touched but would not have held the rifle onto the target / npoa - would the reticle going straight up be a result?

 

[_Windrider_]

Yes we know, Yoda

But what the hell made it change between 2 different spots like that? At some point it drove me nuts like i had gone back in time or something.

Let me ask this. If the rear bag was too low underneath the stock, as in, it touched but would not have held the rifle onto the target / npoa - would the reticle going straight up be a result?

Well recoil will move in path of least resistance right and it should "theoretically" be straight back and if its not its because you the shooter did something. Of course this is all theory and we all know we can never be perfect behind the rifle, especially in other than prone. but i do know, bipods do not hop unless i am doing something wrong. but if the rear bag was too low and the rifle wasn't in that shoulder pocket just right then yeah i could see that happening. ive learned that i need to extend my bipod legs more when i shoot. i used to subscribe to the theory that you had to be as low as possible so i would always leave the bipod on its lowest setting and would be forcing my body into positions so i could see through the scope. well, i now realize i forgot one part of that. you need to be in the lowest position possible while being comfortable if you arent comfortable you are muscling the rifle and changing NPA. i mean it doesnt get any lower than prone right? so i now try to get in the best prone position i can and use the bipod legs as necessary.

 

[TheGerman]

haha

How long did you look for that?

 

[_Windrider_]

haha

How long did you look for that?

as soon as i saw your post. it was the first pic in google when i searched "yoda middle finger"

 

[TheGerman]

It was completely the rear bag coupled with the bipod being 1 notch too high that caused the issue. Did the same spots today, further distances, with the same gun and focused on the initial set up more than I had in the past and I was making easy hits again with the reticle on/near the target the entire time through recoil and then settling back on target 95% of the time.

Amazing what a tiny thing like 1 notch too high on the bipod, causing there to be too much of a gap for the rear bag can make. What really got me was that the gap on the rear bag was the 'perfect' horrible size; too small for one side of the bag, too large for any of the others.

 

[Apnea]

It was completely the rear bag coupled with the bipod being 1 notch too high that caused the issue. Did the same spots today, further distances, with the same gun and focused on the initial set up more than I had in the past and I was making easy hits again with the reticle on/near the target the entire time through recoil and then settling back on target 95% of the time.

Amazing what a tiny thing like 1 notch too high on the bipod, causing there to be too much of a gap for the rear bag can make. What really got me was that the gap on the rear bag was the 'perfect' horrible size; too small for one side of the bag, too large for any of the others.

Oh cool, nice when things make sense.

I know exactly what you mean with the perfect horrible size. You don't want it to be too easy.

 

[elmuzzlebreak]

I'm going to wake this post back up again. I've been having the same issue with my reticle moving up a few tenths of a mil when I'm dry firing prone. I'm really thinking it could be a rear bag issue.

another thing I’m noticing is the rifle buttpad tends to slip down over time. So I’m thinking the lop may be slightly too short.

 

[_Windrider_]

I'm going to wake this post back up again. I've been having the same issue with my reticle moving up a few tenths of a mil when I'm dry firing prone. I'm really thinking it could be a rear bag issue.

another thing I’m noticing is the rifle buttpad tends to slip down over time. So I’m thinking the lop may be slightly too short.

Def a rear bag. I fight my rear bag constantly. I still haven’t found that one. As far as the pad slipping, make sure you have the rifle seated in that shoulder pocket with a little weight forward loading that bipod.

 

[Dthomas3523]

I'm going to wake this post back up again. I've been having the same issue with my reticle moving up a few tenths of a mil when I'm dry firing prone. I'm really thinking it could be a rear bag issue.

another thing I’m noticing is the rifle buttpad tends to slip down over time. So I’m thinking the lop may be slightly too short.

One of two things. Either that’s your natural point of aim and it’s finding it way there naturally as your body moves. Or it’s the natural point of aim and the vibrations from the firing pin spring are enough to settle it in.

It’s likely from not attaching yourself to the rifle and then bringing the rear bag into the equation. If you’re doing any form of the following:

Rifle is on ground with bipod and the rear of the rifle is already sitting on the bag (typically in this situation a gamechanger or fortune cookie or variant). You get down and basically get your body in position.

That’s going to do bad things. Instead:

Have rifle on ground on bipod and no bag. Or rifle in hand. (If in hand, sit rifle down with no bag when you move into position and sit the rifle down). Keep whatever rear bag you choose either in your support hand or on the ground away from rifle.

Position your body square to the target. Move the rifle into position in front of you. While up on elbows, with firing hand, pull the butt into shoulder/collar area. Relax into your firing position. This will slightly load the bipod with just a bit of your core.

You should damn near (or completely) be able to remove both hands and the rifle is supported via collar and bipod. If you wanted, you should be able to easily shoot 1 moa dots without a bag here.

Then bring the support hand in with the bag. You as the shooter do most of the support and the bag just makes micro adjustments. From here you can go into your NPA drills and such.

Phil Velayo has a video called “building the bridge” (or something along those lines) that is very good demonstration.

Here is a pic from a student at Rifles Only we made this adjustment to. I could literally take a pic like this every single class where we fix this “bridge”.

 

[LANCER]

I too, was fighting the rear bag this weekend, and shot a lot worse than usual. My bipod was too high and having to squeeze the bag too hard (inducing muscle shake) I was actually recording the reticle this time and recoil was mainly straight up also.

 

[elmuzzlebreak]

@Dthomas3523 thanks for your great write up and help. Going back a few times and a metric crap ton of dry fire it was a bipod height issue that was shifting my NPA. Also this was leading to an almost death grip on the rear bag. Also removing the rear bag from the initial set up really helped. Thank you!