Just got my new 280 AI from Score High in, outstabding craftsmanship. Went out and did an OCW test today and did max load tests for H4831sc, H1000, and Retumbo. Retumbo won out in velocity with 168gr Berger VLD (hunting). They were seated about .010 off the lands for the pressure test and OCW. So I did an OCW test with Retumbo and here are the results... Looks like my node is 62.7-63.1gr (groups 4 & 5). Group 3 though looks very close to the POI but it's pretty scattered. Probably going to load up 62.9gr and play with the seating depth. What do you guys think?
280 AI OCW Results Confirmation
- Thread starter stanley52
- Start date
I would try Vihtavouri N165 also. my gun likes it the best, I am using 62grains with the 168 Berger and my average speed is 2900fps with a 24" barrel and half moa out far.
I aslo worked with with rl-17 its excellent in mild weather and 40 fps faster than all powders I have tried in my 280AI, but loses speed in cold weather.
Elmer
I agree with the 62.9 area and seating depth... these 168 7mm VLD's are about the fussiest bullets in the Berger line with regard to seating depth. But they'll eventually find a place that works.
We checked the gun works ammo that uses this bullet in their 7mm Magnum chambered rifles, and it turns out they had backed the bullet off between 60 and 70 thousandths from the lands. And those guns do shoot very well, of course.
Dan
We checked the gun works ammo that uses this bullet in their 7mm Magnum chambered rifles, and it turns out they had backed the bullet off between 60 and 70 thousandths from the lands. And those guns do shoot very well, of course.
Dan
Thanks Dan for the confirmation. I actually had a lot if problems with Retumbo, in another aspect, because it was a pretty compressed load and my redding comp. seater was giving extremely inconsistent seating depths, so I decided to load H4831sc since I had that on hand. It was the only powder I possessed that on a max pressure load was not compressed. My loads for the below picture are: 1) 59.5gr 2) 59.9gr 3) 60.3gr 4) 60.7gr 5) 61.1gr 6) 61.5gr. They go across left to right, then continuing top to bottom; center target was a sighter. No silver sharpie to mark it on the target. Load #3 I accidentally dropped 2 of them with the Retumbo shells so I threw 2 of then out. I seated the 168's kissing the lands, but not "in them". Load #5 is clearly the scatter node, subtract 1.5% and it land at 60.18gr which puts you between load #2 & #3. I think the target confirms this excellently, even without all three shots in load #3. Load #2,3,4 all have the same POI with ok group size. Rifle definitely likes h4831sc better, contrary to what I previously thought.
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Appreciate the post on the 280ai ocw, will be doing my own on the 280ai soon hopefully using the 180smks and h4831.
I just realized that picture uploaded upside down in my post about H4831sc. Might be hard to know what I am talking about if you did not know that/couldn't tell ha. And yeah there's some stuff on 280 AI out there but not a lot considering how many people really do shoot it.
