Post by: milldozer on June 09, 2019, 03:14:57 PM
Post by: Crunchy on June 09, 2019, 03:43:00 PM
I started my load workup at 69 grains, and went up in .3 grain increments to 74 grains. Best node was from 71.7 to 72.3. Went with 72 and started adjusting seating depth. Got .49 MOA at 200 yards, but next time out I could not repeat that tight of a group. So either bad shooting day, or something changed. I think I have it figured out now. Just one more trip to verify :chuckle:
Post by: jasnt on June 09, 2019, 03:51:28 PM
Post by: b23 on June 09, 2019, 04:17:21 PM
I use the same primers. I dont think primers effect accuracy as much as they might have an impact on your standard deviation consistency.
:yeah:
There are always exceptions, but for the most part, the only thing I've ever seen change was a little velocity, one way or the other, and better/worse ES and SD. I predominately use Fed. 205M/210M/215M primers and they've worked well for me, but I have friends that swear by CCI's.
Post by: hogslayer on June 09, 2019, 06:17:03 PM
Post by: yorketransport on June 09, 2019, 08:34:08 PM
Post by: hunter399 on June 09, 2019, 08:39:17 PM
Post by: huntandjeep on June 10, 2019, 06:00:20 AM
Cci 200’s or 250’s for everything:yeah: 250's in my 7mm , 200's in the 6.5x284
Post by: milldozer on June 10, 2019, 07:30:12 AM
Crunchy, out of curiosity what bullet/powder are you shooting with 72 grains? Do you know what the velocity is?
Post by: Crunchy on June 10, 2019, 08:21:38 AM
Thanks for all the replies. Anyone have some CCI's they'd want to trade for 215's?
Crunchy, out of curiosity what bullet/powder are you shooting with 72 grains? Do you know what the velocity is?
H1000, Norma brass, and 168 VLD hunters, and 3187 fps.
Not sure how it is possible, but I had my action trued, and new # 5 Benchmark barrel installed. Before that was done, 69 grains would have been upper end of a hot load for the factory barrel. Now I am getting no signs of excessive pressure at 72 grains. Even at 74 grains, no sticky bolt or primer cratering. There was a node at 74 also at 3205 fps but I was getting some ejector marks on the case head so I backed it down to the next node.
Post by: Stein on June 10, 2019, 08:40:16 AM
CCI 200 2,704 fps 31.9 SD
Rem 9 1/2 2,750 16.0
Win WLR 2,735 6.3
CCI BR-2 2,715 4.2
Fed Mag Match 2,754 13.4
CCI 250 Mag 2,724 24.3
Rem 9 1/2 Mag 2,739 6.9
Those were all the primers I could get my hand on for loading that day, I may try others as they become available. In short, my experience in my situation shows primers do matter significantly, I have no idea if the above results would hold true for 7mm, your gun, your load, but it is certainly worth testing.
I was mainly shooting for velocity data but did take notes on groups as well. The fed Mag Match gave me the best group I have probably ever shot (under 1/2"), Rem 9 1/2s were about 1" for the normal and over an inch for mags, CCI mags were about 1", Win a bit under an inch, CCI BR-2 had 3 touching and two flyers, about 1" overall and the 200s were off paper (scope needed adjustment). This is decent info to have but obviously very reliant on the the guy pulling the trigger, wind, etc. I am loading up the BR-2s for future work but also going to keep the Fed Mag Match in the study to see if that group was a fluke or something special. I'm still of the opinion that SD matters a bunch, but testing with an open mind and able to change it when given a good reason.
Post by: milldozer on June 10, 2019, 09:22:50 AM
H1000, Norma brass, and 168 VLD hunters, and 3187 fps.
Not sure how it is possible, but I had my action trued, and new # 5 Benchmark barrel installed. Before that was done, 69 grains would have been upper end of a hot load for the factory barrel. Now I am getting no signs of excessive pressure at 72 grains. Even at 74 grains, no sticky bolt or primer cratering. There was a node at 74 also at 3205 fps but I was getting some ejector marks on the case head so I backed it down to the next node.
[/quote]
Dang, those are cookin. With those 150 gr barnes TTSX my accuracy seems to go to *censored* as I approach 2900 ft/s. 64-65 grains of H1000 seems to be the sweet spot for accuracy, around 2850 ft/s.
Post by: Crunchy on June 11, 2019, 09:21:52 PM
H1000, Norma brass, and 168 VLD hunters, and 3187 fps.
Not sure how it is possible, but I had my action trued, and new # 5 Benchmark barrel installed. Before that was done, 69 grains would have been upper end of a hot load for the factory barrel. Now I am getting no signs of excessive pressure at 72 grains. Even at 74 grains, no sticky bolt or primer cratering. There was a node at 74 also at 3205 fps but I was getting some ejector marks on the case head so I backed it down to the next node.
Dang, those are cookin. With those 150 gr barnes TTSX my accuracy seems to go to *censored* as I approach 2900 ft/s. 64-65 grains of H1000 seems to be the sweet spot for accuracy, around 2850 ft/s.
[/quote]
Yeah it must have something to do with the barrel either heavier contour or that it is 3 inches longer than factory 24 inch.
Post by: hogslayer on June 11, 2019, 09:25:59 PM
Post by: h20hunter on June 11, 2019, 09:28:00 PM