Vertical stringing

[ky99]

I have a new Knight Disc Elite 50cal.Shot 250sst and 300xtp bullets.777 powder with 100 and 120gr. loads.win 209 primers.At 100yds I am getting 4 to 6 inchs of vertical stringing ,windage is holding perfect.Any ideas on what may be the problem?

 

[Anonymous]

Don't know.

Check the barrel screw torque, make sure your barrel is floated, and weigh your powder.

I never could get XTP's to group out of my Elites.

 

[clock]

As RW suggests vertical stringing is often times a bedding problem, however one tip I learned from the guys here is to let the barrel cool at least 10 minutes and 15 minutes if necessay, between shots. I would stay with the 250 SST and 100 grains T-7 or 2 -50grain Pyrodex pellets, as these loads and the SSt shoot good out of 4 Mls I have, Ray

 

[Mark whiz]

I would definitely check the fit between the stock and action/barrel.
I shoot the fire out of my little Knight USAK without cooling the barrel and it has never exhibited any stringing tendencies.
Also, are you running a damp cleaning patch between rounds at the range? That usually helps grouping quit a bit.

 

[big6x6]

I have a new Knight Disc Elite 50cal.Shot 250sst and 300xtp bullets.777 powder with 100 and 120gr. loads.win 209 primers.At 100yds I am getting 4 to 6 inchs of vertical stringing ,windage is holding perfect.Any ideas on what may be the problem?

My first question is...Is this a PROVEN load or is this the first load you have tried in your new Disc Elite? If these are the first two bullets you have tried you need to move on to different bullets. Vertical stringing is nothing but a group and 4-6 inches isn't a good one!

I've found it's usually bullet OR recoil related. If it were me, I'd swap to a 200gr Shockwave OR a 200gr/220gr DeadCenter and try it with 100gr ffg Triple Se7en, spit-patching between shots. I bet you a nickel that will fix it!

Of course check the stock screw bases/rings as well!

 

[ky99]

Thanks for info ,I checked stock screw was tight and can pass dollar bill between barrel and stock.My primers are about 8years old I may stop and get some fresh ones and try that.Also will experiment with other bullets when I can find some.

 

[Anonymous]

I think Chuck is right. It read like a "new" problem to me, but-- it seems more like a gun that has just never been sighted in.

So, you so have to give it a change at letting your gun tell you what bullet it likes. 120 gr. T7 is no starting load, at least for me.

245 gr. Spitfires, .40 / 50 220 and 240 Dead Centers, and even 348 gr. Powerbelts have shot extremely well for me. So has the .44/ 300 Dead Center-- good enough to kill a pig with.

And, the 200 gr. SST's (Shockwaves) that Chuck popped pronghorn with-- those groups were outstanding, for any rifle.

 

[ky99]

The gun is new,Just returned from range with it.Tried new primers no change.tried 250gr.spire point shockwaves with 100gr.777 no change Tried 2 50gr pyrodex pellets with250shockwave better more of a 2.5" round group.Tried 295hpcopperclad powerbelt with 2 50gr pyrodex pellets back to vertical string.Other than the 250shockwave pyrodex pellet load everything has been vertical 3 shot groups with windage holding under a inch.Most 777 loads were 100gr just tried 120gr to see.I shot some primers only off and they do not sound consistant.I am thinking I could have a firing pin dragging or something giving inconsistant ingnition of powder.the primer hits vary when I check them after shooting some will be flush with a small dent ,some with the center of primer pushed way back toward bolt and one with primer mashed flat like a rifle would.The knight book says not to disasemble firing pin further but can one do it at home ?I will keep testing bullets but I really think it is something else.Thanks for all of the replys and please keep them coming.

 

[Anonymous]

the primer hits vary when I check them after shooting some will be flush with a small dent ,some with the center of primer pushed way back toward bolt and one with primer mashed flat like a rifle would.

I've had that happen, and the solution was a simple one. The secondary safety likes to screw itself on-- that's all it was. :shock:

 

[Grouse]

The gun is new,Just returned from range with it.Tried new primers no change.tried 250gr.spire point shockwaves with 100gr.777 no change Tried 2 50gr pyrodex pellets with250shockwave better more of a 2.5" round group.Tried 295hpcopperclad powerbelt with 2 50gr pyrodex pellets back to vertical string.Other than the 250shockwave pyrodex pellet load everything has been vertical 3 shot groups with windage holding under a inch.Most 777 loads were 100gr just tried 120gr to see.I shot some primers only off and they do not sound consistant.I am thinking I could have a firing pin dragging or something giving inconsistant ingnition of powder.the primer hits vary when I check them after shooting some will be flush with a small dent ,some with the center of primer pushed way back toward bolt and one with primer mashed flat like a rifle would.The knight book says not to disasemble firing pin further but can one do it at home ?I will keep testing bullets but I really think it is something else.Thanks for all of the replys and please keep them coming.

Double check bases and rings. Try a different scope to be sure it's not the scope. :idea:

 

[Twanger]

Any chance you're shooting with the fore-end sitting on a hard or springy surface?

That can cause the rifle to bounce and make vertical strings.
I've seem some vertical stringing from 45/40 350gr White Powerstars, but it was less than 1-inch at 50-yds, so I didn't worry too much about it.

Velocity variations can cause vertical stringing, but it would take ALOT of variation to cause 4-6 inches of stringing. Probably many hundreds of fps. I've seen 1" POI shift from 250fps change in MV at 50 yds. If your powder is REALLY bad, maybe that would do it.

 

[ky99]

Have been using a sand bag rest most of time.Also have been holding gun normal with elbow on shooting bench to eliminate that.thanks.

 

[little red]

i shoot a knight disc with 200 gr shockwaves, and 100 gr of pyro rs. If i don't foul the barrol with two shots, it will shoot about 6 inches high the first shot,and 3-4 inches high the second shot. Then it will shoot two inch groups consistently for me at 92 yards. If you are cleaning your gun real good,before you change to another bullet you may have to refoul your barrol. My gun shoots best when dirty, i just dry patch, on both sides between shots, but i do it every time i shoot. Take two deep breaths, exhale slowly, shoot with the end of your trigger finger, pulling the trigger slowly so you don't know when the gun will be going off. It works for me!

 

[Anonymous]

The type of scope, bases, and rings has not been mentioned-- whatever the scope is, have you confirmed it on another rifle?

Are your front bases loose?

 

[ky99]

Scope is a nikon prostaff 3x9 I took it off my 223 rem It was shooting .75 groups on it.I know The ML has more recoil but I do not really think it is the scope but anything is possible. I may have been cleaning bore too well between shots my patches are pretty tight and if they are not fairly wet they will hang up.Thanks again

 

[ky99]

Also I did take scope off to recheck base screws everything was tight.

 

[Mark whiz]

ky99,

When you checked the tightness of the stock screw, did you take it out and remove the action from the stock? My Knight when I got it, didn't have the action & stock settled into each other properly and it literally wouldn't hit the broad side of a barn. Seperate yours and make sure the two pieces are fitting snuggly and properly together. This might help.

 

[Anonymous]

The gun is new,Just returned from range with it.Tried new primers no change.tried 250gr.spire point shockwaves with 100gr.777 no change Tried 2 50gr pyrodex pellets with250shockwave better more of a 2.5" round group.

Time to run some rounds through a chronograph. No way can I call a 2-1/2" group a 4-6" vertical string.

You need to weigh that powder. I read no change to mean still 4-6" with T 7, but group size cut in half with a pair of pellets-- that's significant.

 

[Twanger]

It sure is Randy. I believe that is the 'smoking gun' as they say. Takes me back to my original thought that the powder is FUBAR. Buuuuuuut, it would take something like 500 fps velocity variations to get a vertical string that big. That's a guess, of course. A combination of recoil, the time the bullets stay in the tube, and trajectory can do some mighty weird things. A new can of powder is probably in order. Also, weighing charges might be worth-while, just to see how much variation the volume measure is giving.

 

[Indyultra]

Try tighten the stock screws to 60 inch lbs. Or start at 40 and work up to 60.