Group analysis help requested

[TimberHunter]

Hey All,

If you don’t want to read all the info below here’s a summary: 41.5 some pressure signs, good group with some stringing horizontal. 41 no pressure, pronounced stringing vertical. What would you do next?





Getting back into reloading. Trying to keep it ultra simple and follow forms suggestions to reduce load dev time as much as possible

Long story short, 41.5 shoots pretty well with some horizontal stringing. 41.0 shoots ok but with a lot of vertical stringing. See attached targets. Each indivisible group was shot on a different day. Weather was all similar, only difference is I’d say **on the lower 41.5 group I was not nearly as steady that day so that’s what could’ve opened up that group**

41.5 started showing ejector marks and stiff bolt lifts so I think it’s at or very close to max. I want to be able to shoot this load in the summer and not worry about pressure. 41 has no pressure signs

41.0 velocity: 2681fps - 2723
41.5 velocity: 2702fps - 2755

-6.5cm tikka rough tech. 500 or shot shots down the factory barrel.
- Hornady once shot brass in my rifle that was FL sized
- 143 ELDX
-H4350
-COL 2.810
- this rifle has been known to shoot 143 eldx factory loaded ammo sub MOA at 100 yards with velocity of approx 2675

Also tried one 6 shot group of 40.5 which I included a picture of but that group was fairly poor



Trying to keep this simple.. What would be your next step?

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[Mulyhuntr]

What rifle?

 

[TimberHunter]

What rifle?

6.5cm tikka rough tech. I will edit the post to include that info


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[Mulyhuntr]

For what it's worth my tikka shoots the 147 much better than it shot the 143s. 147s are absolute killers too.

 

[TimberHunter]

For what it's worth my tikka shoots the 147 much better than it shot the 143s. 147s are absolute killers too.

Thanks for the info. In factory ammo my rifle will shoot 143 precision hunter well under MOA but the 147 match factory ammo shoots right at MOA so that’s why I went with the 143s. Guess I could give the 147s a try


Edit: after thinking about it for a minute, I think what you suggest is actually what form is talking about (if you can’t find the accuracy you want in a two loads near max, change power or bullet)


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[Formidilosus]

Hey All,

If you don’t want to read all the info below here’s a summary: 41.5 some pressure signs, good group with some stringing horizontal. 41 no pressure, pronounced stringing vertical. What would you do next?





Getting back into reloading. Trying to keep it ultra simple and follow forms suggestions to reduce load dev time as much as possible

Long story short, 41.5 shoots pretty well with some horizontal stringing. 41.0 shoots ok but with a lot of vertical stringing. See attached targets. Each indivisible group was shot on a different day. Weather was all similar, only difference is I’d say **on the lower 41.5 group I was not nearly as steady that day so that’s what could’ve opened up that group**

41.5 started showing ejector marks and stiff bolt lifts so I think it’s at or very close to max. I want to be able to shoot this load in the summer and not worry about pressure. 41 has no pressure signs

41.0 velocity: 2681fps - 2723
41.5 velocity: 2702fps - 2755

-6.5cm tikka rough tech. 500 or shot shots down the factory barrel.
- Hornady once shot brass in my rifle that was FL sized
- 143 ELDX
-H4350
-COL 2.810
- this rifle has been known to shoot 143 eldx factory loaded ammo sub MOA at 100 yards with velocity of approx 2675

Also tried one 6 shot group of 40.5 which I included a picture of but that group was fairly poor



Trying to keep this simple.. What would be your next step?

Sent from my iPhone using Tapatalk

6 shot groups?

What are the scope, rings, mounts? What rest are you shooting from?

 

[TimberHunter]

6 shot groups?

What are the scope, rings, mounts? What rest are you shooting from?

Thanks for chiming in. They are 6 and 7 shot groups, I used to do 3 shot groups before reading your reloading thread. I was going to do 10 if those looked good but didn’t want to waste power and bullets if 6/7 shot groups were not good or in the case of 41.5 was at pressure.

SWFA 10x, warne rings and bases. Rings torqued, bases torqued and blue locktite. Front bipod and rear rabbit ear bag. Crosshairs are usually not moving. This rifle/scope hasn’t been problematic in the past, it shoots the 143 precision hunter factory ammo under MOA consistently


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[Formidilosus]

Thanks for chiming in. They are 6 and 7 shot groups, I used to do 3 shot groups before reading your reloading thread. I was going to do 10 if those looked good but didn’t want to waste power and bullets if 6/7 shot groups were not good or in the case of 41.5 was at pressure.

SWFA 10x, warne rings and bases. Rings torqued, bases torqued and blue locktite. Front bipod and rear rabbit ear bag. Crosshairs are usually not moving. This rifle/scope hasn’t been problematic in the past, it shoots the 143 precision hunter factory ammo under MOA consistently.

The issue is that if you overlay those 41gr and 41.5gr groups- they are round’ish 1 to 1.5 MOA groups. I would load 10-15 rounds of 41gr and shoot them. I doubt you will see a vertical line. Let the barrel cool every 5-7 rounds or barrel mirage will cause stringing.

 

[josebigsky]

I’d ask what goal for the load is? If you are trying to have all shots shooting into one hole then change brass to Lapua, try a different primer. Maybe a match primer or switch from CCI to Federal, try seating depth changes. 1000th at a time. Don’t shoot off a bipod, shoot off a sandbag with a rear rest of sandbag too. All these have made a difference for me when chasing all shots touching. My two cents.

 

[Mulyhuntr]

How far off the lands are you? My standard is .02" with all my tikkas because they all shoot well at that.

 

[TimberHunter]

The issue is that if you overlay those 41gr and 41.5gr groups- they are round’ish 1 to 1.5 MOA groups. I would load 10-15 rounds of 41gr and shoot them. I doubt you will see a vertical line. Let the barrel cool every 5-7 rounds or barrel mirage will cause stringing.

Ok I will give it a try.

To confirm, referencing your implied reloading thread, I’m not at the point where I want to change power/bullet? Ideally I’d be looking for around .75moa at 100 which I and the gun should/are capable of


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[Formidilosus]

Ok I will give it a try.

To confirm, referencing your implied reloading thread, I’m not at the point where I want to change power/bullet?

For what?

Ideally I’d be looking for around .75moa at 100 which I and the gun should/are capable of

What will .75 MOA do for you that 1 MOA won’t?

 

[TimberHunter]

For what?





What will .75 MOA do for you that 1 MOA won’t?

Sorry meant to say simplified not implied lol

You are correct, I’m not good enough to see the difference of that .25moa at any distance beyond 100yards. That’s a mind shift I’m working on, spend less time f-ing with a load at 100 and more time at distance gaining experience and improving my effective range


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[TimberHunter]

UPDATE:

Neighboor came over yesterday before I loaded up more eldx’s and after a while talking with him he gave me some 140 Berger VLDs to try.

Loaded H4350 at 38grains, 39,40,41,41.5 and 42 to test for pressure and velocity. I also loaded 5 at 41.5 since that’s a known powder node for the 6.5cm.

COL=2.800 which equals about .150 jump to lands
Brass= Hornady once shot

I was very impressed with how they shot. 38,39,40,41,1-41.5 and 42 were shot without the can using a magneto (POI shift from the 41.5 group). The entire powder spread only results in 1.5” on the target. Then the 41.5 shot a sub.75moa group. So looks like I need to buy some bergers lol

Likely will load 10 at 41.7 since judging by the velocity/pressure group, 41.5 may be on the edge of an accuracy node

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[stanginthe11s]

I have to ask because im confused. are you chasing accuracy or velocity? seems to me you're chasing velocity. you stated that a slower factory load shot better but are refusing to drop down to that speed even though the rifle is telling you to.
other than that, im with everyone else in that you will not likely notice the difference.

 

[TimberHunter]

I have to ask because im confused. are you chasing accuracy or velocity? seems to me you're chasing velocity. you stated that a slower factory load shot better but are refusing to drop down to that speed even though the rifle is telling you to.
other than that, im with everyone else in that you will not likely notice the difference.

Thanks for the clarification question. 40.5 was a very similar velocity to the factory ammo and it was one of the worse groups. This really stumped me but I chalked it up to Hornady is likely not using H4350 in their ammo any longer so just because I can replicate the velocity with H4350 doesn’t mean I will get the same type of grouping on paper at 100

I agree with the aspect that I would likely not notice a difference. My initial question was based around wondering why 41.5 has a little horizontal stringing and 41 has a decent amount of vertical stringing (4 different groups on 4 different days) but I’m not sure that that question is important like Form was alluding to


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[hereinaz]

If it’s under an inch, go shoot it. If you want to look at anything, look at the most consistent velocity if you are shooting past 600.

You could be the cause of the vertical stringing.

My experience is that Bergers shoot better for me out of my guns and friends as well.

 

[Pharmseller]

How far off the lands are you? My standard is .02" with all my tikkas because they all shoot well at that.

And you’re still within magazine length?

If I loaded any of my 7mm-08s .02” off the lands I’d be way over mag length.




P

 

[Mulyhuntr]

And you’re still within magazine length?

If I loaded any of my 7mm-08s .02” off the lands I’d be way over mag length.




P

243 (108s) and 6.5 cm (147s) with factory mags and 223 (75s) with MT mag.

 

[Pharmseller]

243 (108s), 6.5 cm (147s) and 223 (75s) with MT mag, yes.

So aftermarket magazines?




P