Mini groups within 5 shot group

[bob_dobalina]

What would you say about consistently having groups of 2 shots grouping, but those groups not grouping together. Pictures to explain. One pic is 175 LRX, one is 180 TTSX, both at approximately same seating depth (deep). When I don't seat as deep the groups just open up. Could it be my scope? Shooting form?

 

[DrMike]

I would consider the groups in total rather than thinking that I see smaller groups within the larger group. The pattern is witnessing what the rifle/load is producing for you; it describes what you are going to see in the field. The issue lies in the load and not in your scope/regimen or some other factor.

 

[bob_dobalina]

I would consider the groups in total rather than thinking that I see smaller groups within the larger group. The pattern is witnessing what the rifle/load is producing for you; it describes what you are going to see in the field. The issue lies in the load and not in your scope/regimen or some other factor.

Thanks DrMike. What would your advice generally be to tighten up?

 

[DrMike]

If standard deviation or extreme spread is tight in your test samples, playing with seating depth is the quickest way to tighten a group. It is always possible that there is not enough room to seat the bullet deeper or there is another mechanical restriction inhibiting seating the bullet longer. In that case, you are driven to look at another powder and/or another bullet. Generally speaking, the LRX does like a jump to the lands. I normally start this monolithic bullets with a 0.100 jump, which can mean that it intrudes into the powder column quite a bit. If that is not feasible, there is little left except to turn to another powder and/or bullet.

 

[JD338]

Mike is spot on. Seat your bullet deeper.

JD338

 

[slickrem]

Your two question probably answered your problem. Check scope action mount screws, then the scope rings, and check the action screws. Blue lock tite for the action and scope mount but leave the rings be if they are aluminum, if they're steel, then lock tite them too. Before you fool around with your loads.....check the stuff I listed. Always start with the obvious potential stuff first. Good follow through, breathing etc...

 

[ShadeTree]

Loose screws will not produce your results. You can check them, but highly unlikely that is your problem. Loose screws cannot produce consistent results bouncing back and forth between 2 points like you're getting. It will result in groups with no control, not back and forth between precise points.

1 or 2 groups doesn't tell you much, but you're saying it does this consistently. And when you made changes in seating depth the group size changed, but the double grouping remained the same. Am I understanding correctly?

There are no absolutes until you eliminate them, but to me that is a scope problem. The crosshairs bouncing back and forth between their 2 tension points internally. Will sometimes stay in the same place for a shot or 2 then back to the other position. Back and forth.

If you have another known good scope laying around, that would be the quickest way to eliminate that variable. If it ends up not being the scope, you're really no farther behind in fixing it. Unlike chasing your tail on loads and it ends up being the scope. No wrong way really to get to the same end, just my opinion that I'd start with the scope and eliminate that possibility.

 

[Ridge_Runner]

group within a group says one thing, your rifle doesn't like the seating depth you are using. I try to start most bullets around .030 off the lands to start depending on the rifle.

 

[slickrem]

group within a group says one thing, your rifle doesn't like the seating depth you are using. I try to start most bullets around .030 off the lands to start depending on the rifle.

the other group is too far away and isn't seat depth related. He needs to check out his scope and mounts. Standard Deviation isn't an issue here.

 

[slickrem]

Loose screws will not produce your results.... You can check them ?

Can't hurt to start there..

 

[Ridge_Runner]

the other group is too far away and isn't seat depth related. He needs to check out his scope and mounts. Standard Deviation isn't an issue here.

ok, you know way more than me, been at it 50 years and can't learn annything

 

[RL338]

Without knowing rifle and caliber it’s hard to come to solution to your issue. My CVA was doing the same thing with 250gr Hornadys. I took a big swing in changes and now it make repeatable results.
With Barnes bullets I start with their listed COAL and it usually works out.

 

[ShadeTree]

Can't hurt to start there..

Sure. If you have the rings apart why wouldn't you check the base screws, that's just common maintenance even with no issues. There can always be a first for anything but something loose on a rifle has never resulted in consistent results for me under recoil.

He is basically cutting bullet holes at 2 different spots roughly 1" apart in a identical diagonal pattern with 2 different bullets according to the pictures, and he says it does that consistently. That's actually hard to do.

So logic would tell me to start with the scope as they can do that. It's just where I would start if were me, but my first solution to the likely problem could be wrong. I acknowledge that about myself everyday.

 

[KinleyWater]

You know, I have a question of my own - do you experience this with any other rifle? If you try shooting the same drill (2 groups of 2) with a different rifle, do you get the same results? If you do, I would guess it's you, not the rifle(s). If this is unique to this rifle, it isn't you. Whenever there is an issue in accuracy, always begin with the shooter and then work your way forward.

 

[Bruce Mc]

Let me tell y'all a story about a 257 Rob mod 70 featherweight USRA variety that belonged to my bil. It shot the same type split groups. If he adjusted for the left group to be center the other group would shoot right and to the left if he zeroed the right group. So, no scope issue. He took it to an old school custom gun maker and had it pillar bedded. Well it got worse. The groups were very small only now they were 1/2 " further apart. Let's talk to Winchester aka USRA. Send us the rifle we'll look it over. Beautifully rifled barrel, but the bore was eccentric. Now comes the rub, they wouldn't rebarrel the rifle and put it back in the altered stock. So they sent him a new rifle and returned the stock.

 

[bob_dobalina]

You know, I have a question of my own - do you experience this with any other rifle? If you try shooting the same drill (2 groups of 2) with a different rifle, do you get the same results? If you do, I would guess it's you, not the rifle(s). If this is unique to this rifle, it isn't you. Whenever there is an issue in accuracy, always begin with the shooter and then work your way forward.

I would say just this rifle. I have a Tikka that consistently puts shots touching, but the groups are nicer. I did check the scope and action torque, thanks guys. The LRX, I can't seat any deeper, I'll be out of bearing surface. The TTSX I could go a bit deeper. I can't seat any closer than .15" off the lands with this bullets and my magazine constraints, and they shoot better deeper - they are .22" off the lands! So maybe it's a symptom of that seating depth but I don't have alot of options. Accubonds shoot well in this rifle .05" off the lands, but I would have to single feed them.

 

[slickrem]

I would say just this rifle. I have a Tikka that consistently puts shots touching, but the groups are nicer. I did check the scope and action torque, thanks guys. The LRX, I can't seat any deeper, I'll be out of bearing surface. The TTSX I could go a bit deeper. I can't seat any closer than .15" off the lands with this bullets and my magazine constraints, and they shoot better deeper - they are .22" off the lands! So maybe it's a symptom of that seating depth but I don't have alot of options. Accubonds shoot well in this rifle .05" off the lands, but I would have to single feed them.

You're all over the place with bullet depth, out of bearing surface?? You are going to extremes. Weatherby's have a crazy deep seating depth and long throat, shoot extremely well. I know I have one.

BruceMc mentioned about an eccentric bore... didn't elaborate on what the actual problem was with it.

When you say you checked you action screws, you use a torque wrench or just by hand? I don't use a torque wrench.

Even though TTSX bullets have a coating to prevent fouling doesn't mean they won't at all. Curious how well you clean your barrel. Or I believe something is binding up somewhere to cause this issue.

 

[slickrem]

Let me tell y'all a story about a 257 Rob mod 70 featherweight USRA variety that belonged to my bil. It shot the same type split groups. If he adjusted for the left group to be center the other group would shoot right and to the left if he zeroed the right group. So, no scope issue. He took it to an old school custom gun maker and had it pillar bedded. Well it got worse. The groups were very small only now they were 1/2 " further apart. Let's talk to Winchester aka USRA. Send us the rifle we'll look it over. Beautifully rifled barrel, but the bore was eccentric. Now comes the rub, they wouldn't rebarrel the rifle and put it back in the altered stock. So they sent him a new rifle and returned the stock.

When you say eccentric, what was wrong with it ?

 

[KinleyWater]

I would say just this rifle. I have a Tikka that consistently puts shots touching, but the groups are nicer. I did check the scope and action torque, thanks guys. The LRX, I can't seat any deeper, I'll be out of bearing surface. The TTSX I could go a bit deeper. I can't seat any closer than .15" off the lands with this bullets and my magazine constraints, and they shoot better deeper - they are .22" off the lands! So maybe it's a symptom of that seating depth but I don't have alot of options. Accubonds shoot well in this rifle .05" off the lands, but I would have to single feed them.

Okay, so we can reasonably say that it's not an issue with having a different cheek weld/ sight picture/ etc. between groups. That's good. I might suggest trying some factory ammo. I don't expect that it will be as accurate, but see if the problem persists. Before you shoot (I suppose you could do it after), measure the COAL, this should give you a standard reference point and take your hand loads out of the equation.

 

[bob_dobalina]

You're all over the place with bullet depth, out of bearing surface?? You are going to extremes. Weatherby's have a crazy deep seating depth and long throat, shoot extremely well. I know I have one.

BruceMc mentioned about an eccentric bore... didn't elaborate on what the actual problem was with it.

When you say you checked you action screws, you use a torque wrench or just by hand? I don't use a torque wrench.

Even though TTSX bullets have a coating to prevent fouling doesn't mean they won't at all. Curious how well you clean your barrel. Or I believe something is binding up somewhere to cause this issue.

These bullets are seated at .21 off of the lands, how am I all over the place on seating depth? Barnes will typically shoot well seated very deep. I guess my AccuBond comment was unrelated, just trying to say it does shoot other bullets well at different depths, but that's a different bullet. On the LRX, I wouldn't want to go any deeper, but I bet I'm seated about what their factory ammo is, I don't think it's "extreme." Action screws were checked with a torque wrench. Thanks for your comments.