I finally got some range time today. I was able to do alot of shooting and load work. Unfortunately there was a bit of wind and gusts fom 10-15 MPH going left to right. It was sunny to partly cloudy and about 80 degrees.
I went specifically to shoot the 7 STW and I was shooting 180g Berger VLDs. I didn't chrony anything as I'm looking for a group.
I tried 3 diffrent powders, US869, Retumbo, and H1000. All shots were at 100yds and I allowed quite a bit of cooling between groups. I did shoot 5 shot groups so I could throw out the shots effected by gusts or my pulling the shot and still have 3-4 shots to establish a group. I was origionally going to shoot a 3 shot group if conditions were calm, the conditions weren't and I won't be getting another range day for a while, so I decided to shoot the 5 shot groups.
US869 wouldn't group under 2" so I'm eliminating it as a canidate right now. I was suprised with retumbo it actually shot better than H1000 in this rifle.
Here are the 3 best groups I could come up with in 10mph wind.....
The bottom picture is 75g of H1000, this was 1 grain under book max, and the best load out of 4, H1000 loads. As a side note, all of the h1000 loads exhibited horizontal stringing. I'm thinking that this was due to the wind, but not sure, vertical was good on all of them as well. I'll probably revisit H1000 on a calmer day.
Retumbo looks good and I'm leaning to the 79g load. All loads were so they could eject live from the action if needed. They are off of the lands quite a bit, but no where close to magazine length. I will probably play with the seating depth as well.