Improving horizontal spread..

[mbohuntr]

I have finally got a decent combination for 600 yds, My vertical spread from my last trip with very mild crosswinds.. 1-5mph. is .3MOA, but my horizontal spread is 1.1 MOA. I realize the wind is likely a bigger culprit, but I noticed my sight picture moving horizontally with my heartbeat... How do I stop this??

Right now, I use a heavy front bag, and a squeeze bag on the rear shooting seated. I pull the stock in fairly tight with one hand. The other hand doesn't touch the stock.

Thanks in advance..

[Robinhood]

How do I stop this??

Reduce your magnification. Relax

[J.Baker]

Cut caffine out of your diet.

[sharpshooter]

Take some tranquilizers and shoot faster...

[squirrelsniper]

Horizontal is either bad wind reads or poor trigger pull. That's kind of harsh, but the screw-up is on your end somewhere.

[Iowa Fox]

Not saying its the issue but different squeeze bags can make a tremendous difference in grouping.

[mbohuntr]

Horizontal is either bad wind reads or poor trigger pull. That's kind of harsh, but the screw-up is on your end somewhere.
LOL, I don't take criticism personally, my rifle shoots WAY better than I can.. I know I can improve, I just need pointers.. thank-you everyone! Keep em coming..

[yobuck]

Stop shooting at paper and start shooting at clay birds. Then shoot at the pieces.
Then the only thing that matters is if you hit it and had fun.
What you won't know or learn from it wont really matter anyway.
Don't hesitate to cheat either. lol
In time by doing it this way your heart rate might even improve.

[Marine]

My rifle shoots better than me also and horizontal spread is something I deal with too. Try different methods of hold and rest to see what works best. Doing it the same every shot is key part. I have resorted at times to using a bungee cord wrapped over the palm swell to a lead sled when working up loads to remove as much error on my part as possible. Whatever works.

[CFJunkie]

We all have found little things that change our intended point of impact unexpectedly even in calm winds.

One thing that makes my heartbeat visible in a high powered scope is too tight a cheek weld.
Once I consistently set up a cheek weld and didn't try to press my cheek too tightly into the stock, I stopped seeing heartbeats.

I also find that not setting the stock in exactly the same position in your shoulder causes horizontal movement in the point of impact.
When my shoulder mount is out of the notch in my arm socket and the rifle recoils, my sight picture is moved to the right and after recoil the aim point is to the right and so is the point of impact.
When I set the stock correctly, the rifle comes straight back and my rifle is aimed at my aim point and the point of impact is at my aim point.

Stock positioning is the cause of the majority of my shooter induced horizontal variation.
It has taken a lot of practice to get my set up correct the majority of times and my group averages, even in winds above 5 mph, are smaller and there is far less variation.

[Evlshnngns]

Whats cartridge/bullet and how many shots in the group? That could have been a lot of 10's and x's, with some 9's.

[mbohuntr]

We all have found little things that change our intended point of impact unexpectedly even in calm winds.

One thing that makes my heartbeat visible in a high powered scope is too tight a cheek weld.
Once I consistently set up a cheek weld and didn't try to press my cheek too tightly into the stock, I stopped seeing heartbeats.

I also find that not setting the stock in exactly the same position in your shoulder causes horizontal movement in the point of impact.
When my shoulder mount is out of the notch in my arm socket and the rifle recoils, my sight picture is moved to the right and after recoil the aim point is to the right and so is the point of impact.
When I set the stock correctly, the rifle comes straight back and my rifle is aimed at my aim point and the point of impact is at my aim point.

Stock positioning is the cause of the majority of my shooter induced horizontal variation.
It has taken a lot of practice to get my set up correct the majority of times and my group averages, even in winds above 5 mph, are smaller and there is far less variation.

Now that you mention it, I was pushing pretty hard on the cheek piece.. That and trigger pull.... Hmmmm

[mbohuntr]

Whats cartridge/bullet and how many shots in the group? That could have been a lot of 10's and x's, with some 9's.

I was running short on time, and I was shooting 3 shot groups trying to re-set my come-ups after changing from 4064 to 4895. The temperature sensitivity was too much for reliable hunting. The last group I shot was on target, with one 10, one right in the 9, and one left at a distance of 7" from the second. The vertical spread was around 2" if I remember correctly. 600 yds.

I switched because the morning temp might be 20's, and the afternoon temps in the 50's.. too much guesswork for my liking... I would be zero'd on a 85 degree day, and barely on paper at 50 degrees..

[Robinhood]

Varget

[mbohuntr]

Varget


I didn't know about Varget... I'll have to try a test with some of that next year... If we can still buy it....

[Mozella]

........ snip................, but I noticed my sight picture moving horizontally with my heartbeat... How do I stop this??
......... snip...........

I have the same problem. I solved it with a much lighter hold. F-Class rules require you to shoot from the shoulder but it doesn't say how firmly your cheek weld must be. My rifle is in contact with my shoulder with my right thumb behind the trigger guard and my index finger on the trigger. My left hand lightly touches the top of the stock and pushes down to fine tune my vertical aim. My cheek doesn't touch the stock at all, but my left hand, the one touching the stock, also contacts my cheek very lightly more or less as a reference point as I adjust my head position to look through the center of the scope.

Typically I set my initial aim just low of the desired POA and by pressing down I can bring the aim point up to exactly where I want it. I'm in my mid 70's with poor eyesight, but I can hold a pretty steady aim on the 600 yard spotter disk and hold on the bottom edge, 3/4 diameter, or centered, if that makes any sense. In other words, I can aim for the spotter disk in any of five desired vertical increments. A younger man could obviously do even better.

If I hold the desired aim nice and steady until the gun discharges, the bullet goes where I want it much of the time (at least as far as vertical is concerned) but if I use a poor trigger technique or try to rush the trigger squeeze........ not so much. Proper trigger technique is an important factor when it comes to small groups. You already know that and so do I, but knowing it and doing it are two different things.

Of course, I can't read the wind as accurately as I wish, but at least I'm able to hold a steady aim with a light rifle hold. If I really grip it with a strong cheek weld. my heart beat makes the aim point jump all over the place, just like yours, but I suspect my blood pressure is higher than yours, so it's even worse for me.

Try a lighter hold and see if it helps.

[mbohuntr]

:eagerness:

[s3silver]

Yep, agree with Mozella. Relax and vary your grip hand tension and see what happens.

[CFJunkie]

Aberdeen Proving Grounds did a study of temperature change on the velocity of .308 military rounds.
They claimed that there was 1.7 fps change in velocity per degree F.
I think that was for a IMR4064-like powder but, just like factory ammo manufacturers, the powder they use comes in very large lots that may be slightly different than what we can buy off the shelf.

I did some checking through QuickLOAD software for powders that I regularly use and found that their data for IMR4064 would come very close to that number for a .308.
Other powders varied from around 1.1 to 1.6 fps per degree F.

The change in velocity as temperatures drop will cause a change in point of impact not only down but I find it also creates slight change in windage because the bullet stay in the rifling slightly longer (maybe up to 0.02 msec. out of 1.256 msec. for a 24 inch barrel) and it apparently changes the spin rate slightly.

[mbohuntr]

Well, that explains why my ladder test looked like I had a seizure...