Horizontal stringing.

[Pwhite11798]

I have been doing load testing on a couple different powders. I got to the point where I felt it was time to tune seating depth. Except for the first string I shot I experience horizontal stringing the entire other 9 strings. I came to determine that I was the problem of the cause. I was shooting from a f class bipod and rear bag on a concrete bench that had weather erosion causing pretty good pits in the top. The range is sectioned off with 15' concrete walls running the length of the course of fire. My question is would it be beneficial to put carpet under the bipod to give it something to ride on. And what setups are you guys using when shooting ftr to keep things consistent shot to shot.

 

[Tim Singleton]

I don't know what range you are testing at or how much your setup may have to do with the problem.
That said
I have found this to be a pretty accurate statement
Tune out horizontal with seating depth
Tune out vertical with powder charge or tuner

 

[Pwhite11798]

I got the powder charge tuned in. No vertical trying seating depth from no jump to .050 jump in .005 increments all had horizontal stringing except the .050 jump which was the first string I shot.

 

[ab_bentley]

What's your trigger weight?

Adam

 

[Pwhite11798]

1 lb

 

[savagedasher]

I got the powder charge tuned in. No vertical trying seating depth from no jump to .050 jump in .005 increments all had horizontal stringing except the .050 jump which was the first string I shot.

Shoot the .050 jump Larry

 

[Pwhite11798]

I don't disagree larry. I just thought that shurly I was doing something fundamentally wrong. The string I shot with no jump was one ragged hole next to another ragged hole and inch apart that's what really got me questioning the fundamentals and bench setup. I also considered setting up an air rifle so I can shoot at home at 25 or 50 yards just to keep up with the fundamentals a little better.

 

[savagedasher]

I don't disagree larry. I just thought that shurly I was doing something fundamentally wrong. The string I shot with no jump was one ragged hole next to another ragged hole and inch apart that's what really got me questioning the fundamentals and bench setup. I also considered setting up an air rifle so I can shoot at home at 25 or 50 yards just to keep up with the fundamentals a little better.

Rear bags and stock pressure is is common. Let someone else shoot the gun -- it can be you. Larry

 

[Pwhite11798]

Working on setting that up.

 

[LHSmith]

By mentioning that the range has 15' high walls leads me to think you are discounting wind as a factor. Many/ most ranges that hold sanctioned short range BR matches have tall woods flanking both sides and any competitor can tell you that is far from the case. Use flags when doing load work-up shooting without them is just "plinking" and will not yield reliable results.
To add to Tim's list for horizontal problems - try different neck tension.
And don't overlook inconsistent cheek pressure and pulling the trigger on the side of the shoe instead of straightback from the center.

 

[jsthntn247]

When I get horizontal stringing I'm normally too far in the lands. When I get too far out it goes vertical.

 

[Scott Harris]

1 lb

What cartridge are you shooting? Bullet, charge? Rifle weight?

 

[CharlieNC]

If you're working up a load for FTR, why are you shooting off a bench instead of prone? My cause of horizontal stringing results from too much cheek pressure when prone.

 

[Fotheringill]

One sure way to take yourself and your bipod out of the equation is to take off the bipod, attach one of the "benchrest" fronts that screw right into the bottom rail up front and use a front rest. It very well might be you putting just a little should pressure forward, or breathing, which is going to move the bipod.

I learned this with my .223 F/TR Savage. It was a bad choice for shooting benchrest, but is good to go now with a 3.5" wide plate on the front and a front benchrest.

 

[eric n]

My LOP for prone is uncomfortable on a bench and throws off my cheek weld giving me crappy groups.
How much stringing are you seeing?

 

[Pwhite11798]

It was uncomfortable shooting from the bench with this set up. On thing I did notice while shooting early in stringing was that, if I wrapped my thumb around the palm swell of the stock would pull left in dry firing and if did wrap my thumb on the swell at all it would pull right during dry fire. So I just rested my thumb in the middle of the swell just behind the back end of the action.

 

[Pwhite11798]

Loads I am working on are all lapua sr.308 175gr. Match burners. Br4 primer
Varget 44.4 gr
4064 44.1 gr
4166 43.9 gr

 

[Brians356]

Try placing your trigger thumb on the back of the trigger guard, and use a simple pinch to squeeze the trigger. Don't grip the stock at all with either hand. Try not to put any pressure on the butt with your shoulder, or put any pressure on the stock with your cheek. The rifle will hop more under recoil, and move farther out of position, but this should minimize any unwanted off-axis forces on the stock when firing. Compare this technique with your thumb wrap methods while dry firing, you might notice a lot less relative motion of the reticle on target.
-

 

[500Stroker]

I subscribe and use the KISS principle.
You have something fundamental/simple wrong. Rather that jumping in guessing at some technical fix. I suggest you go back and shoot powder ladder, after you pick a powder node to shoot your vertical will likely go away.
This my sound arbitrary but your wont laugh when it works.
Good Luck