Need help analyzing these groups, horizontal stringing

[DMS1]

OK, I am shooting a remington 700 VTR in 223 with a 4.5-14mm long range leupold. I have removed the muzzle brake, and the trigger is tuned to about 3lbs. I have filed the bumps on the stock, but due to the warp from molding, it still makes contact with the barrel, but it is pushing more on the left side of the barrel. The three groups below are typical of what I get. I am shooting black hills 52 grain remanufactured match hollow points, and 69 grain match hollow points. The second group is a random mix of 2 52gr and 3 69gr. They shoot the same point of impact at 100 yards in my rifle. The groups shown are from atlas bipod prone, unsupported from the rear. All of the groups are from shooting sessions of 30-50 shots. The dots on the paper are each about 1" in diameter. The five shot groups are fired in under 1 minute for 5 shots. I can get 4 shots in under 1/2", but I always seem to get a horizontal flyer. It is not the last shot. Woud this be from the stock? I am thinking about trying an HS precision or bell and carlson, but would like to wring everything I can out of this setup first. Any ideas or suggestions from more experienced shooters than me?

 

[Miltiades]

I would say that your stock touching your barrel on the side is most likely the cause. Firing a shot every 12 s or so may not give adequate time for the barrel to stop oscillating and depending on the timing of the next shot, pressure may be applied on one or the other side relative to the relaxed state. As an experiment, try to shoot slower, something like a shot every 30 s or even better every 1 min and see what the horizontal dispersion is.

 

[fiddler]

or your barrel is warming up and pressing harder on the side of the stock. Same advice as above, go shoot something else for a while before you take consecutive shots. Check to see how well your barrel is floating cold vs warm.

 

[JW Precision]

You have to get the stock cleared so no matter what it doesn't touch the barrel at any time. Then try the groups again.

 

[AKD]

I would work on ur breathing first.

 

[Moose284]

Aren't those barrels triangular? I like to have at least a 5-6 masking tape wraps clearance, for the barrel then bed.

 

[thesilverfox]

The first thing I would do different is setup a couple of wind flags. And try to shoot in a similar wind condition. If you shot in a condition you think is the same and you still get groups you can't explain then I would say your rifle is out of tune. A properly tuned rifle will react the least in a changing wind condition. Remember those 22 cal bullets only need a liitle wind difference to move and inch at 100 yards. I would also try supporting the rear of the rifle as to try to reduce the human factor. At least then, you can isolate the problem

 

[TCBF]

I would work on ur breathing first.

- Breathing should string vertical, not horizontal. If it was the last shot, it might be 'last shot syndrome' but it isn't. If there is no 'body' reason (moving an elbow or a hand, high vertical triangle, etc.) then the 'tech' answers above are worth a try.

 

[Shooter ----/]

The groups shown are from atlas bipod prone, unsupported from the rear.

This should be the first thing you fix.

How can you do group testing when you still have the human variable in the equation?? Without the rifle fully supported, your just practicing.

Support the rear with a bag and try again. God knows I love an excuse to shoot more!

 

[Longshot]

Wind and/or trigger control are your problems.

 

[CyaN1de]

DMS1 you did not state what the weather conditions were when you fired these groups.

Wind and Mirage can put bullets out by those margins quite easily. Since you stated that you are not using a rear bag of any sort to support the rear of the stock, it is impossible to help narrow the problem down. Too many variables.

Go out on a windless, miragless day (preferably early in the AM), shoot the same ammo off the bench with a good rear bag and see if the groups remain the same as what you posted. If they do then you can start looking at the stock, trigger control (3lbs is like pulling a truck, at least to a guy who's used to using a 4-6oz trigger), ammo, etc.