Horizonal ?

[Link]

This is what my horizonal looks like at 300. There was a little mirage but I don't think this much? 6BRA 2 different bullets. 1-8 t 105 bullet. Top is new Alpha. Bottom is 3 fire Lapaua so I don't think it is the brass. Flags set at 3 locations. Wind 6* at 4-6 mph.
What would you try next?

ty Don

 

[rjtfroggy]

personally I would try a different load, way too much spread.
Or push the seating depth in another 0.007 and try it there.

 

[mac86951]

Rear bag twist?

 

[acloco]

Left to right.....is person behind the buttplate.

 

[JFrank]

This is what my horizonal looks like at 300. There was a little mirage but I don't think this much? 6BRA 2 different bullets. 1-8 t 105 bullet. Top is new Alpha. Bottom is 3 fire Lapaua so I don't think it is the brass. Flags set at 3 locations. Wind 6* at 4-6 mph.
What would you try next?

ty D

Im finding decent accuracy above 2900 fps

 

[Homerange]

Google once told me a cause of horizontal stringing could be loose action screws and for a rifle I had just acquired this indeed was the case.
YMMV

 

[Link]

Google once told me a cause of horizontal stringing could be loose action screws and for a rifle I had just acquired this indeed was the case.
YMMV

I should have added a Glued in Panda.

ty Don

 

[Dusty Stevens]

You may have had flags out but you missed something. A bad load will have more vertical

 

[JimSC]

What would you try next?

ty Don

easiest fix is load up 50 at that same powder charge and seating depth. Then take them to the range along with a portable press, seating die and a set of calipers. Move the seating depth in .003 on three rounds and shoot them, then another three, keep adjusting seating depth until the groups become round. The groups may go vertical before rounding out

this is assuming your hold, cheek weld and wind calling was not the issue

 

[Ccrider]

My knee jerk thought was seating depth and you may be on the lands too far. That’s just a guess based on what I have encountered.
I would move in to 100 to try and diagnose the problem, still using wind flags.
If it’s the shooter, could be bag set up, flinch, trigger pull, to name a few things.
If it’s not one of those things, I would adjust seating depth and powder charge in that order. Once I found the best seating depth I would adjust powder charge.

Be methodical. Change/work on one thing at a time and see if you get improvement.

 

[LHSmith]

Rule out parallax issues before changing the load. Also, seat depth = horizontal issues. Improper trigger pull, inconsistent hold.

 

[ShootDots]

There are some possible causes for you horizontal stringing.
1.) improper set up of the front and rear bags where they are not in alignment;
2.) "shooter error", where you may have pulled the trigger and not EVERYTHING was the same in your hold;
3.) a "remote possibility" that the erector system holding your "windage" on your scope is in need of repair. Believe it or not that DID in fact happen to me;
4.) however, in MY opinion, the "most likely" culprit is as @Ccrider stated, the "seating depth" needs to be changed!
I have found that if you have a pretty "tight" horizontal, your rifle likes the bullet and the powder>>>but NOT the location of your seating depth. I think if you follow his advice in his reply, you may very well "fix" your dilemma..

 

[CaptainMal]

Those that know me also know I'm too stupid to tune properly. Then I beat them anyhow. Well, been playing with 108 Bergers in a new barrel I had chambered in BRA for a back-up to my competition BR rifles. Now "everybody" knows the Berger 108's like to be jammed.

Everybody is like "they say". Who the heck is "everybody" and "they"? I found a load with Precision powder and liked velocity, ES and what seemed like an easy tuner tweak but for one thing at 600 yards - horizontal. Three sessions of what I thought was bad wind conditions and my inept ability to read things all had nasty horizontal results with literally no vertical of consequence at 600 yards. I was always between touch and jam .010" as per normal history with the 108's.

Last time out I did a seating depth test starting at, to me, a huge jam of .015". Three shot groups were horizontal with some both horizontal and vertical as I moved in to "touch" and then started moving out. Between - .015 and - .020" the horizontal stopped and repeatedly, there were nice round groups.

I played and played a few times and that pattern repeated. Never would I believe Berger 108's worked best with a jump but there it was. No horizontal and nice groups. Barrels are like women - all different in what they like.

Glad I read the topic as I want to use this rifle Saturday at a Manatee club 600 shoot. The topic had me now look at the ammo I was going to use and discovered I did not load any. Glad it is raining as I now have work to do.

I better "JUMP" to it.

 

[K22]

Personally I wouldn't make any decisions based on a 300 yards target because shooter error, wind, and mirage are all magnified.

Instead, I would go back to 100 yards on a overcast day with little to no wind and shoot a couple of 5 shot groups off a solid front and back rest, taking my time to focus on my technique before I'd change the load.

 

[JFrank]

I created my post #5 simply because of what I noticed was your FPS ( mid 2700) whereas most people including myself are above 2900, im not an expert but this maybe a clue into the open/horizontal groups you are seeing coupled with side wind of course.

I could be way off also.

 

[divingin]

Last time out I did a seating depth test starting at, to me, a huge jam of .015". Three shot groups were horizontal with some both horizontal and vertical as I moved in to "touch" and then started moving out. Between - .015 and - .020" the horizontal stopped and repeatedly, there were nice round groups.

I played and played a few times and that pattern repeated. Never would I believe Berger 108's worked best with a jump but there it was. No horizontal and nice groups. Barrels are like women - all different in what they like.

I found this article rather interesting; it's the summary of a 3-part look into jump:

Bullet Jump Research: Executive Summary & Load Development Tips

This is the last post in a series of articles focused on bullet jump research that has been conduct...

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