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6.5CM Berger 144 LRHT: Help me find the right seating depth

Hi
I worked up a load for my 6.5CM rifle
Confirmed the powder charge @ 41.3grs H4350 @CBTO= 2.119 which is 20thou off the lands from the initial measurement.
I ran the seating depth test from 2.121 with 3 thou increase in seating depth down to 2.0520

the combination shoots great as you see I have 3shots in one hole at CBTO 2.076
I have a few amazing nodes in the 0.1s but the ES sucks,
I will use this gun for shooting paper up to 1000 and steel up to 1600yards!

-I am looking for the 2 best consecutive groups, what if they don't have the best ES?

-should I go with those 2 with a little bigger group but lower ES or just go with the smallest groups even they have higher ES?

Rifle:
Defiance Ruckus
Bartlein 28" 1:7.5 M24
EC Next Gen Tuner brake set at 0

Load:
Lapua SRP
CCI 450
Berger 144 LRHT
41.3grs H4350


elevation at the time of shooting was about 700ft and temp 50-46F

Screenshot 2023-12-13 230252.png

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I like 2.115 and your 2.076. I would go back to those with maybe 10 round strings to check speed and see what you have, 20 rounds each would be even better. You seem to have some big jumps in SD also (but only 3 shots), be sure your brass prep and loading process is on point.
 
That looks like a solid test with some reliable data. The ES is the last thing I would worry about. I have two rifles that shoot amazingly well out to a mile and have worse SDs than that. Id stick to the paper and let it be your guide.

I would take the 2.109" CBTO load and test powder charge with it in 0.1 grain increments on either side on paper to see how wide your velocity window is before the load opens up. Then I would test neck tension at 600 or 1k to see what bushing held the best vertical.

FWIW, I have found the Rem 7.5 primers to be amazing game changers on some 6.5 CM SRP loads. If I had the results you have posted I wouldn't be looking to dump the CCI 450s but I have seen them make some dramatic improvements in 6.5 CM loads with H4350 and 144 and 153.5 Bergers in a friend's rifle.
 
That looks like a solid test with some reliable data. The ES is the last thing I would worry about. I have two rifles that shoot amazingly well out to a mile and have worse SDs than that. Id stick to the paper and let it be your guide.

I would take the 2.109" CBTO load and test powder charge with it in 0.1 grain increments on either side on paper to see how wide your velocity window is before the load opens up. Then I would test neck tension at 600 or 1k to see what bushing held the best vertical.

FWIW, I have found the Rem 7.5 primers to be amazing game changers on some 6.5 CM SRP loads. If I had the results you have posted I wouldn't be looking to dump the CCI 450s but I have seen them make some dramatic improvements in 6.5 CM loads with H4350 and 144 and 153.5 Bergers in a friend's rifle.
Thanks man
I have a box of fed 205m maybe use those to see if I get a flat spot @2.109? Cause my node with 450s was 41.2-41.4 and 41.3 had the best ES/SD in several tests
 
Just recently worked up a load for a friend of mines Savage Tactical in 6.5 C M with the Berger 144 gr. LRHT and H-4350. Pleasantly surprised with the performance of the load in Lapua SRP virgin brass.

144 GR. BERGER L R HYB T 2.192 O M 2.935 COL T/L B S .483 B C .655
POWDER H-4350 41.8 GR. PRIMER CCI BR-4
SEATED @ 2.182 O M 2.925 COL .010 OTL
 
Out of curiosity
If you find 2 consecutive groups that have same POI but the speed is 10fps lower on the lower end of the node is it that 10fps lower speed, tight group and low sd, would you still load on that node? Lie 2.0058 and 2.0055
Super difficult for me to drive 2hrs for 600yard range now, I need to go prepared not wasting time and ammo
Thanks
 
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I would consider chronogarph data (SDs) as the least important item and shoot groups at disatnce with what looked promising on target. It is often possible to get excellent LR groups with little vertical dispersion for loads with higher SDs and conversly quite easy to get poor LR groupings with loads that have low SDs. I have two loads for F Class that will clean a 1,000 YD target and have SDs over 10.
 
I would consider chronogarph data (SDs) as the least important item and shoot groups at disatnce with what looked promising on target. It is often possible to get excellent LR groups with little vertical dispersion for loads with higher SDs and conversly quite easy to get poor LR groupings with loads that have low SDs. I have two loads for F Class that will clean a 1,000 YD target and have SDs over 10.
Thanks man
 
I would consider chronogarph data (SDs) as the least important item and shoot groups at disatnce with what looked promising on target. It is often possible to get excellent LR groups with little vertical dispersion for loads with higher SDs and conversly quite easy to get poor LR groupings with loads that have low SDs. I have two loads for F Class that will clean a 1,000 YD target and have SDs over 10.
Absolutely, low S Ds will not always produce small groups at any distance.
 
Groups are what tell you what your rifle shoots best. MV is nice as is ES and SD but they are just numbers, groups are results. Shooting known distance you can adjust your scope to the velocity you get. My best load so far with the 144 Hybrid in the 6.5 CM is: H4350 41.5 grs. Lapua SRP, CCI BR4. MV= 2,885 fps in a 31" Brux barrel jumping 0.015"
 
Update
I drove 2 hours to get to the range today but they didn’t allow me to set a target no more than 400 yards
Anyway I attached the target below
There was some nasty winds from 6 and 9 o’clock, 3-6mph
I wish I had an electronic target lol.
It wasn’t my best shooting cause I always shot at steel and its my first time shooting at the paper this far, but to be honest the results are very confusing and I dont know what to pick.

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