horizontal stringing...part II
Well after some more expermintation here is the results. Any input will be deeply appreciated, I sure would like to fix this problem. All of the groups are 10 shots each. No wind, homemade shooting bench (very heavy, 400 lbs) and rifle support. rifle 1903A3, 2 groove barrel 1.5X6 Burris Signature scope. 100 yard range. Very careful cheek weld, squeezing the trigger like an egg shell, 2 shots were "called" a bit out as the trigger broke, but did not show up on paper that way.
Load 1) 130 hornaday, shot 1 3/4" round group a bit to the rt.
Load 2) 168gr sierria, shot 1" oval group
Load 3) 173gr cast with H4895 horizontial group about 1" X 3"
Load 4) 180gr Speer, 1 1/8 X 3" group
load 5) 190gr hornaday MK 1" X 4 1/2 group.
Does anybody have input as to why the groups get horizontal with heavy bullets?
Thanks, I do value your input!
Load 1) 130 hornaday, shot 1 3/4" round group a bit to the rt.
Load 2) 168gr sierria, shot 1" oval group
Load 3) 173gr cast with H4895 horizontial group about 1" X 3"
Load 4) 180gr Speer, 1 1/8 X 3" group
load 5) 190gr hornaday MK 1" X 4 1/2 group.
Does anybody have input as to why the groups get horizontal with heavy bullets?
Thanks, I do value your input!
0
-
Just a thought? Rifleing twist might have something to do with it. Heavier the bullet, faster the twist, what I always heard. Perhaps the heavy bullets aren't being stabilized sufficiently at the velocity your shooting them at? 
0 -
A lot of the time horizontal stringing is a bedding problem . Ive run into this several times. Vertical dispersion is usually an ignition or unequal velocity problem.
If there is any irregularity in the barrel channel it can cause horizontal stringing. the channel has to be perfectly smooth . the action has to be well bedded so it cant torque or change position from shot to shot. if the channel has a small ridge or bump anywhere in the bottom, the barrel can stop in its recoil vibration on one side or the other of the spot . It will shoot side to side accordingly. Occasionally I find a rifle that actually has an audible "click"in it. If you hold the end of the forearm in one hand and the barrel a few inches out from the end of the forearm ,in the other hand ,try to move the barrel back and forth sideways . If you feel a click or bump as it moves across an uneven spot ,there is the problem. The heavier the bullet the worse it will be due to recoil and vibration patterns.
Scrape out the channel real smooth and glas-bed the action .
I hope this can fix your problem0 -
it might also be the rifle recoiling upward with inconsistent restraint. heaveyer bullet=longer barrel time=more torg upward, hold the rifle down into the sandbags with a death grip & try again. 0 -
Before you crack what bedding there may be in your barrel channel; why not slide a strip of typing paper between the barrel and stock to feel for sticking, snagging, grit or debris? Start at the tip of the forend and slip/slide the paper down to the action, feeling for obstructions or stuff. That'll get you close to the spot if one exists, and show if your barrel is indeed, free-floating.
You might also check the crown for accumulating lead/copper or for slight unevenness at the rounded portion at the very end of the rifling.
One last tip when shooting strangely; I always (when shooting over a chrony, or grouping a new load) rock the rifle side to side after I load it, and before I settle back into position to shoot. It might help; It may be superstition, but it works for me.
"Qui non est hodie cras minus aptus erit" --OVID0 -
hmmm, me thinks the harmonics is off...... 0
Please sign in to leave a comment.
Comments
5 comments