Horizontal stringing

[NJStricker]

Over the weekend I was out shooting my Lyman Trade Rifle in .50 percussion. This was the first time I'd had a chance to shoot it beyond 25 yards or so. I shot at 50 yards, from a rest, and my shots were fairly consistent in elevation, but had about a 20 inch spread horizontally. I was shooting Hornady round balls over TC pre-lubed round patches. Powder was Pyrodex (I want to use this canister up before I order some real BP), and I tried both 80 and 85 grain loads (I'm trying to work up a hunting load).

Any suggestions on how to tighten this group up?

Thanks guys!

 

[longcruise]

Could be wind, position, flinch, ???????

That's a lot of spread. :shocked2: What was the vertical spread?

 

[biliff]

20 inches of horizontal dispersion at 50 yards would have me taking a hard look at the sights. Something is sliding around.

 

[Little Wattsy]

Over the weekend I was out shooting my Lyman Trade Rifle in .50 percussion. This was the first time I'd had a chance to shoot it beyond 25 yards or so. I shot at 50 yards, from a rest, and my shots were fairly consistent in elevation, but had about a 20 inch spread horizontally. I was shooting Hornady round balls over TC pre-lubed round patches. Powder was Pyrodex (I want to use this canister up before I order some real BP), and I tried both 80 and 85 grain loads (I'm trying to work up a hunting load).

Any suggestions on how to tighten this group up?

Thanks guys!

It "CANT" be the load, powder, bal etc or it would HAVE to impact up and down as much as side to side....You would see a spray in a circle type of pattern...Its more like (as mentioned already) a loose sight, or SERIOULSY pullingon a hard trigger, or .....

 

[BrownBear]

Is the front sight shiny? I've seen that much variation when you have strong light coming in from one side, especially if the light intensity kept changing over the course of the shoot. Any time I have a shiny front sight and the light is bright, I flick my Bic and blacken it. Horizontal stringing goes away.

If none of that applies, I'd be looking hard at the combo of your rest and your followthrough after the shot. If your forend rest wasn't firm side to side, it's pretty easy to envision the gun sliding around a bit after the hammer drops but before the ball exits the bore.

 

[Trench]

You said you were using up an old can of Pyrodex. How old was it? Is it possible that there was such wide variation in pressure that vertical stringing occurred?

 

[longcruise]

But his is horizontal!

I'm thinking like others have suggested to check the integrity of the sights!

 

[Zonie]

When you say you were shooting from a rest, does that mean that your arms were supporting the rifle and your elbows were on the bench or does it mean you had rested your rifle on some sort of blocks or cushions?

I've seen a few folks who rested their guns on some blocks and then bent down to try to look thru the sights to align the rifle with the target.
When they do that they are never able to really do a good job of aligning the sights. That can lead to wide horizontal dispersions while the fact that the gun was actually resting on the blocks made the vertical errors on the target very small.

Assuming you are really holding the gun and looking down the sights for there to be a horizontal dispersion of 20 inches at 50 yards the sights would have to be misaligned by +/- 1/8 inch.

 

[ozark57]

I agree with Zonie. I have seen this before in shooting modern guns. Verticle strings can be had from jerking the trigger. Horizintals can be had from a too stiff pull , or not supporting the gun. When you rest the gun, if it is not in a secure bench rest, sand bag front and rear forming a "saddle" at each end. Hold the gun when you fire by seating it in the bags with a little pressure. Only with a mounted machine rest can you let go of the gun, or release your hold during firing.
Sounds to me like you are moving the gun horizontaly while pulling the trigger.

 

[NJStricker]

Thanks guys, that gives me several things to look at.

I'm pretty confident in the stability of the gun--I shoot lying prone with the barrel over a McMillen portable rest. Both elbows on the ground, butt in firm contact with my shoulder. The trigger pull is pretty good--my guess is just under 4 pounds (less than some of my newer cartridge rifles). But, I don't shoot this gun that often, so the unfamiliarity may play into it.

As for sights, they seem sturdy. Dovetailed front and back, rear sight is a stock Lyman sight with key for elevation adjustment. The front sight is shiny. I'll have to blacken it.

 

[NJStricker]

The Pyrodex is a few years old, but I didn't have any problems with my TC Renegade a few weeks ago. . .

 

[NJStricker]

Could be wind, position, flinch, ???????

That's a lot of spread. :shocked2: What was the vertical spread?

Vertical spread was only about 3 inches. . .

 

[cmdrted]

A few other things to check, is the tang and all associated screws tight? Also do the wedge pins go in with thumb pressure only or do they have to be pounded in? Are you lining up the sprue tdc? Look at the muzzle end, make sure there issn't a burr in the rifling, inspect all around the crown for abnormalities. If the gun checks ok like the others said, maybe your bench technique for this rifle. It has a more "pregnant" cheek piece than a TC, maybe you're varying your cheek weld applying varying amounts of pressure, this would certainly move a group horizontally also. Good luck, these are some of the most accurate production guns, they will perform if you do your part.

 

[paulvallandigham]

Have you tried using a "sighter" on the target? I found I shot much smaller groups with open sights ( and my admittedly older eyes) if I folded over a piece of paper, and put the point of the triangle against the Black Bullseye, with the top point being just below the center of my target. Others put the sighter above the BULL, so that they bring the front sight up to that point, and then squeeze off the shot.

I find my windage problems are vastly reduced, and vertical stringing also tends to disappear.

I use this technique when I am working up loads for guns with Open sight, to eliminate my own human errors influencing the groups.

 

[OB OBrien]

Paul said; "if I folded over a piece of paper, and put the point of the triangle against the Black Bullseye, with the top point being just below the center of my target."

Paul, do you mean put the triangle on the target ?

 

[NJStricker]

If I'm understanding him correctly, he's using the point on the triangle as the point of aim rather than trying to find the middle of the black circle bullseye. It makes sense, especially when shooting smaller caliber rounds, to have a single point rather than a 1" or larger circle to aim at. As they said in The Patriot, "Aim small, miss small."

Circular bullseyes are fine for scoring competitions. I actually make up my own sighting targets with scrap paper and a black marker. My bullseyes are 1 inch diamonds, and I aim "Navy" on the bottom point of the diamond.

 

[paulvallandigham]

Yes. Staple or tape the "sighter" to the target. I use business cards, turned to make a Point to the center of the target at 50 yds. At 100 yds, I can't see the business cards well enough over open sights, so I go to construction, or notebook(typing) paper. Anything will do. If I had some old 5 x 7 index cards, I would use those as sighters on my 100 yd targets! As long as you don't shoot off the " Point", you can re-use your sighter( I did tell you I am Cheap, didn't I??? :blah: ).