Odd Grouping Characteristic

[T.A.Sharps]

What could it be if your grouping seems to spread in a pattern streaching horizontally?

I have a rifled shotgun that seems to group 3" vertically, but sometimes spreads it about 6-8" horizontally.

I can't think of what type of specific movement this would represent.

I was thinking maybe jerking the trigger as it would be the only constant mostly side ways movement I can think of shooting from a rest.

What do you all think it could be?

 

[DoubleTapDrew]

Using a rear sandbag? Is it centered correctly in the bag? Are you canting the rifle at all?

 

[Welding Rod]

I have zero experience with rifled shotguns, but stringing in any direction is not uncommon in rifles due to barrel heating.

That is why IMO high round count targets are not so much a test of a gun's useful accuracy as a test of their abilty to resist stringing due to barrel heat.

 

[NCsmitty]

Is it a pump shotgun? If so, pay attention to the barrel nut, it may need to be snugged tighter.




NCsmitty

 

[Lee Roder]

randomness

 

[Driftertank]

Your shoulder is getting tender after the first few rounds, and you're tensing up your shoulder.....

I dunno. I'm useless.

 

[benEzra]

I'm no shotgunner, but make sure your hand position and tension are consistent through all shots. It's amazing how little shifts in body position or support tension can alter a gun's point of impact.

 

[Jubjub]

What's the range, and how windy is it?

 

[Ky Larry]

I have no experience with rifled slugs but I've had this problem with my rifle reloads stringing vertically. I heard/read somewhere that it can be caused by underignition. I switched to a magnum primer in my .30-06 and the problem went away. I've heard that horizontal stringing is caused by poor bedding in a rifle. Don't know about shotguns. Good luck and keep us posted.

 

[Carter]

I'd go with pulling sideways from the front hand when trying to keep a solid grip and compensate for the recoil...or jerking the trigger.

 

[rangerruck]

what kind of shotgun and what kind of rest? if it is a break bbl, no wonder, if you are moving around the front rest, from spot to spot on the front of the rifle, then that is a prob , too. Lastly , as it heats up, it is going to expand the bbl, and that then is going to touch the side of the stock channel. This will def start throwing shots sideways...