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6.5 CM 144gr Long Range Hybrid Target load data

Hi Everyone
Please help me choose the right powder charge for my 6.5 CM

components:
Berger 144gr LRHT
CCI 450
Lapua SRP 1x fired
H4350

I did 2 tests, first one 3 shot groups and second one 5 shot groups on a different day
For first test barrel had 100 rounds down the tube, second test 150 rds.

So after I found 41.3 to 41.7 is the area I want to play with, I went ahead and loaded 5 rounds each from 41.2 to 41.6
Same exact brass prep
Powder RH was monitored and it was the same, for the second test temp was probably 10deg warmer

Last time 41.3 and 41.5 gave me really low sd but the speed jumped a bit

I see 41.5 has a low sd on both tests
But there is no similar speed +- 0.1 grs

Should I just go with the 41.5 and test with 20 rounds? Or You think it’s better to test 41.6 to 41.9 in 0.1 inc to see if there ie any node there?

3shot groups se/es Low speed

41.3 2792. 1.2/3 low 2791
41.5 2814. 1.6/4 low 2812
41.7 2817 6.9/17 low 2808
41.9 2822 4.5/11 low 2817

New 5 shots
41.2 2799 4.7/13 Low 2795
41.3 2802 9.1/23 Low 2792
41/4 2803 5.8/17 Low. 2793
41.5 2816 5.2/12 Low. 2809
41.6 2828 2.5/6 Low 2825
 
I have found the 144 to be very forgiving and in my 260 Ackley they liked the same charge as the 140s. In the Creed though I have found 41.5gr of H4350 to be my pet load in just about every one I mess with with 140s all the way up to the 147 Hornady.
 
What do they look like on paper at intended ranges? IMHO, that is more important than super low ES/SD numbers.
This. ^^
Low ES or SD numbers never won a match.
Never did say what your jump is?
Check on paper and see what produces the smallest groups.
You can use 3 or 4 shot groups, as long as your confident on your shooting skills.
Then move on to 5 shot groups once you've narrowed down a load or two,
to see if those loads work out.
 
This. ^^
Low ES or SD numbers never won a match.
Never did say what your jump is?
Check on paper and see what produces the smallest groups.
You can use 3 or 4 shot groups, as long as your confident on your shooting skills.
Then move on to 5 shot groups once you've narrowed down a load or two,
to see if those loads work out.
Jump is 20 thou
 
A post above advised against using SRP. I strongly disagree. I have shot over 20k out of Lapua 6.5 CM SRP . Many with your exact load. Standard deviations of 5-7, always fantastic accuracy. Shot in temperatures in the teens, no problem.

On the other hand I bought 500 Lapua LRP. I had some large primers I wanted to use up. It was very frustrating. Nothing worked. Sold those cases.
 
Update
Went to the range the other day and did some 5shot strings from 41.2 to 41.9. There is a few small groups at higher charges but that wasn’t what I was looking for, confirmed the 41.3 to be the best powder charge for this gun.
COAL: 2.911 (20thou off the lands)
1st row: 41.2,41.3,41.4,41.5
2nd row: 41.6, 41.7, 41.8, 41.9

C1734FA3-0896-441B-BA4D-4F3CBF8749EA.jpeg
3E407815-6910-4214-B92D-38A6B2FE6494.jpeg68D10BFF-5D4F-4FC4-A0F1-22C7B202C719.jpeg2BA85A28-1CC4-4636-9F92-FC94D2763254.jpegEA0AE1B6-A08B-4734-9CEE-8214F2B59976.jpeg
 
41.5 looks better to me. It may not have quite as good of deviation numbers according to the chrono but thats not what the target is telling to me. I would play with seating depth a little and see what happens or least shoot both loads out at some distance and see what that shows you.

Edit to add. Great shooting either way looks like you got a keeper.
 
41.5 looks better to me. It may not have quite as good of deviation numbers according to the chrono but thats not what the target is telling to me. I would play with seating depth a little and see what happens or least shoot both loads out at some distance and see what that shows you.

Edit to add. Great shooting either way looks like you got a keeper.
Thanks man,
I really like that too
Bolt start to feel a little bit heavy at 41.8, I was to stay away from it as much as I can, 10 shot string at 41.3 didn’t have any bolt lift and barrel at 110deg. Knowing that 41.5 is only 0.3grs below pressure, should be reliable? bolt lift after 10-15 shots?
 

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