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Analyze my group- What to do next?

jt13

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Jul 13, 2017
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Tikka T3
7mm-08
Nosler Accubond 140 gr.
46.0 IMR 4350
CCI 200 Primers
COL: 2.830

12 rounds- 30 seconds between shots- 5 minutes between groups

All shot through chronograph about 15 ft from muzzle
-Average Velocity-2705
-Low-2687
-High-2722
-ES- 35

The velocity is extremely consistent so I was hoping for better results on paper. I'm no Chris Kyle but most shots felt darn good, certainly not far enough off to explain the flyers at the top of the group. All shot out of a lead sled on a bench. Im pretty consistantly a <.5 MOA shooter from a bench.

What should I try differently to bring this together? Seating depth? Primers? Bullets?

Screen Shot 2018-08-31 at 3.53.14 PM.png
 
I'm not sure I see a problem. Shoot it as is. No antelope, deer, or elk is going to escape because you are short half minute of precision.
 
Ditch the lead sled!!!! Seating depth test is what I would do next if trying to tighten the group some. How did you settle on 46.0gr?
 
I’d try a different powder. I wouldn’t be happy with that. Especially with a tikka and accubonds. I also think you can do better with the velocity. Or this late in the season go hunt and tinker with it this winter. Brent’s right, it’s not going to matter at modest ranges.
 
12 shots in roughly 1 1/2" is pretty darn good I would say. I would suggest waiting longer between shots. 30 seconds is not much time and I bet that after 12 shots the barrel was pretty warm. Try a 5 or 10 shot group at the most. Do two separate 5 shot groups and wait a couple minutes between shots for each group and about 15 minutes between the two 5 shot groups.
 
Ditch the lead sled!!!! Seating depth test is what I would do next if trying to tighten the group some. How did you settle on 46.0gr?

I load tested from 44.0 to 47.0 and 45.8 and 46.1 yielded the most consistent groups so I went for 46.0 as it's in the middle and a nice round number.
 
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12 shots in roughly 1 1/2" is pretty darn good I would say. I would suggest waiting longer between shots. 30 seconds is not much time and I bet that after 12 shots the barrel was pretty warm. Try a 5 or 10 shot group at the most. Do two separate 5 shot groups and wait a couple minutes between shots for each group and about 15 minutes between the two 5 shot groups.


I did my best to keep her cool but the pain in the but is that the 2nd shot I fired was one of the highest on paper and the gun was definitely cool then!
 
I’d try a different powder. I wouldn’t be happy with that. Especially with a tikka and accubonds. I also think you can do better with the velocity. Or this late in the season go hunt and tinker with it this winter. Brent’s right, it’s not going to matter at modest ranges.

Any suggestions? I've also tried varget with inconsistent results
 
I'm really liking the results I am getting from Alliant powders these days. I would try some Reloader 16. Here's a link to a recipe they have online: http://www.alliantpowder.com/reload...?gtypeid=2&weight=140&shellid=70&bulletid=482

Also I have had good luck with Hodgdon Powders as well. If the Reloader 16 doesn't pan out you can try some H4350.

I never could like Varget, I know some guys do really well with it in the 7mm/08, but I just had better performers.
 
I'd load another few test groups and fire them not from the lead sled. See what happens. After that either seating depth test or switch powders.
As stated above that load will kill out to moderate range but I fully understand wanting the most accuracy from your rifle.
 
What part of shooting out of the lead sled leads to inaccuracy? I see it as a common recommendation but never quite understood the reasoning.

If i had to guess it would be something to do with keeping a proper cheek weld
 
Yes cheek weld is one factor. Also the way you grip the rifle, how the rifle recoils and how it's controlled. Also with weight in the sled all the energy can lead to cracked stocks and broken scopes/mounts.

Do you use a bipod? I'd try a group or 2 from a bipod/rear bag setup and see how you like it.
 
That grouping is not terrible, but not consistent enough to determine any likely cause. 3"+ groups are easier to put a finger on than 1.5". Honestly, it could just be that it's not a super accurate rifle. Could be a bedding issue, but that usually causes shots to string. What kind of scope,are you running? High quality rings and bases? I would start somewhere around .040 off the lands and load up 3 rounds of powder charges in half grain increments. Try to cover a lot of the spectrum from low to max charge weight. One range of charges should stand out. Take that charge and and load more 3 shot groupings of different lengths every 10 thousandth from the lands on out to whatever seems too short. Eliminate one thing at a time. Too many people will look into multiple causes of inaccuracy at the same time without isolating what it is.
 
I agree with the one thing at a time approach. You may want to try different primers though. on some guns not too much difference, others it can be quite a bit.
I've had my best luck with Federal Bench Rest and worst with CCI
 
I noticed you said 45.8 and 46.1 yielded the most consistent groups, but changed to 46 for simplicity.

Every gun is weird and might have an accuracy node that it likes at a particular velocity.

Load up some in those two weight ranges and try again.
 
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