Shot group question

[cabelasken]

i have a 300 WSM that needs two fouling shots before it starts grouping. It is a 1/2" shooter after that, but the first two can be 1/2 to 3/4" off center.

 

[SSG Graybush]

I have a fierce 28 nosler carbon fury. Using 168 gr vld Berger bullets with adg brass and h1000. I have a guy that is good at working up accurate loads and he has great numbers for this load/rifle and the barrel has been broken in well, over a hundred rounds through it. Both he and i have shot several groups at 700 yards and can hold groups to a half minute. But there always seems to be one and sometimes 2 shots that open the group to 7 or 8 inches. He is going to try upping and lowering the charge by 2 tenths of a grain. Is there anything else we should be trying? What would you do?

I would try .1 gr increments not .2 and maybe try seating the bullets short by 10 thou, separate them by cbto and then seat them to the desired cbto turning your micrometer die down in 1 thou increments. This gets all your cartridges to within 1.5 thou of your desired cbto. And try to get your ES under 15 fps. If not you'll get vertical dispersion

 

[Professor Doolittle]

I have a fierce 28 nosler carbon fury. Using 168 gr vld Berger bullets with adg brass and h1000. I have a guy that is good at working up accurate loads and he has great numbers for this load/rifle and the barrel has been broken in well, over a hundred rounds through it. Both he and i have shot several groups at 700 yards and can hold groups to a half minute. But there always seems to be one and sometimes 2 shots that open the group to 7 or 8 inches. He is going to try upping and lowering the charge by 2 tenths of a grain. Is there anything else we should be trying? What would you do?

Unless the flyer is dead vertical this could be wind gust. Side wind can cause vertical errors in addition to the horizontal error.. What happens at 100 yards? Is the flyer still there?

 

[SSG Graybush]

Its like it needs a "warm" up shot to get going. Its a light barrel so after 3 shots, she starts getting warm.
Didn't know if I should split the sight in between the shots or use the first shot since I will be at cold bore when hunting.
I'll check all the screws tonight.

Cold bore zero your hunting rifle. And know where it shifts to warm. And make the first shot count.

 

[flintlock hunter]

The experiences I've had with this situation have been bedding problems.

On the first shot not staying in the group, I've had a lot of luck using Birchwood Casey Barricade since it takes very little, and there is no need of removing it before firing. Once it's dry it doesn't affect the first shot. In fairness, I heard Ballistol also accomplished the same thing, but I never tried it for anything other tjan removing rust from used muzzleloaders.

 

[Julie]

The few times I've ran into that it has been something mechanical with the gun. Stock, base, scope, etc. real pita. Only recommendation is to take everything apart and re torque and look for any problems.

I had a Ruger M77 in 22-250 that would shoot well under an inch at 200 yards; SOMETIMES. Other times, it would shoot well over 2 MOA. I couldn't figure out the issue. I took everything off it, defatted everything and reassembled it using locktite. I had the action pillar bedded, barrel floated and more. It just wasn't consistent. I took it to Africa with me and fortunately, it was shooting great for my guide so I sold it to him and bought a M-700.

 

[Clem Bronkoski]

I'm just going to be the devil's advocate here and, while all reaponses are good, it could come down to shooting technique. A repositioning of the stock on the rest, cheek pressure, how your rifle sets in your shoulder, really any difference can cause flyers at long yardage. I haven't been shooting long range long but I've seen guys shooting even at 100 yards shoot groups largee than the rifle was capable of due to poor shooting technique.

 

[Warrior74]

I have a fierce 28 nosler carbon fury. Using 168 gr vld Berger bullets with adg brass and h1000. I have a guy that is good at working up accurate loads and he has great numbers for this load/rifle and the barrel has been broken in well, over a hundred rounds through it. Both he and i have shot several groups at 700 yards and can hold groups to a half minute. But there always seems to be one and sometimes 2 shots that open the group to 7 or 8 inches. He is going to try upping and lowering the charge by 2 tenths of a grain. Is there anything else we should be trying? What would you do?

 

[Warrior74]

I have a fierce 28 nosler carbon fury. Using 168 gr vld Berger bullets with adg brass and h1000. I have a guy that is good at working up accurate loads and he has great numbers for this load/rifle and the barrel has been broken in well, over a hundred rounds through it. Both he and i have shot several groups at 700 yards and can hold groups to a half minute. But there always seems to be one and sometimes 2 shots that open the group to 7 or 8 inches. He is going to try upping and lowering the charge by 2 tenths of a grain. Is there anything else we should be trying? What would you do?

I have a browning max lr in 28 nosler using same h1000 ADG brass and mine does the same thing 3 to 4 shot dead on and 1 or 2 flyers..

 

[Riverguy]

Here are some numbers from the loads from my reloader friend. He has done ladder tests.
77.7 h1000
3123 fps
ES-7
SD-3.1
20 thousandths off lands

I ordered 2 boxes of 20 each of 180gr Berger vld hunting and 160gr long range accubonds from fierce so we will see how those fly when i get them.

 

[Paulstarr]

If this happens when the gun gets hot take a look at the thread between the barrel and the action, if this thread is poorly machined the expansion moves the barrel independently from the action, resulting in flyers.It's worth a look.

 

[Riverguy]

The barrel gets cooled between shots.

 

[RH300UM]

I'm just going to be the devil's advocate here and, while all reaponses are good, it could come down to shooting technique. A repositioning of the stock on the rest, cheek pressure, how your rifle sets in your shoulder, really any difference can cause flyers at long yardage. I haven't been shooting long range long but I've seen guys shooting even at 100 yards shoot groups largee than the rifle was capable of due to poor shooting technique.

I've seen this affect groups more than any other thing. Especially with out a adjustable cheek piece.
Then there is the dreaded recoil flinch. Checking the bubble level each shot.
All shooting technique that has to be repeatedly honed on.

Case in point
CHRISTENSON Arms ridgeline. 2 different cheek welds or touch points because the stock doesn't allow a solid cheek weld

 

[TxPhred]

I would have to throw the "firing pin spring" in for a possible solution. A weak pin can cause inconsistent ignition. Learned this on an F-class vlog. In the scenario where there is an unexplained flyer(s) in a string of fire, not necessarily the same number round within the string of rounds. He just started getting flyers.
A fellow shooter asked if he trusted his reloading. Yes- he did, friend said check your firing pin spring, he did and was noticeably shorter than a new one.
Spring replaced and no more flyers.