I’ve got a 21 inch tikka 300 wsm and use RL17. Tried all sort of loads with the 178 eldx, playing with seating depth and powder charge but couldn’t get a good tight group. Best I found was 62.9 gr of rl17 with a col of 2.855 which sends the 178 eldx at about 2890 fps and was getting about 3/4 - 1 moa.
Currently just running 180gr interlocks for now with 59.2 gr of rl17 with a col of 2.855, getting 2670 fps and getting 1/2 moa. Smashes sika in the bush but also good for the odd 500 yard shot.
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