I am having trouble finding certain powders for Hornady's listed loads for 300 JHP in 458 WinMag. Can I substitute loads for the 450 Marlin.
Specifically 50 grains RL-7 with 300 JHP with a goal of 2000 fps. Will I be safe and close to the money?
I used 60 grains of RL7 with the Hornady 300 JHP. I never shot them over a chrono but I believe I found the data in the Sierra manual.
Thank you beretzs. That boosts my confidence. What velocity did Sierra show in the manual for 60gr? OK, I am reading a little closer. You may not have that manual handy. If not, no problem. I was thinking to up the charge to 55 or if the book shows 2,000 with 60, then I would load that. At this point, I am splitting hairs. I will flip a coin
If the 300gr bullets are not accurate, then I may try something a little heavier. My limited experience is the biggest variable for accuracy is the bullet. I took a chance on 100 of these Hornady. These days, I am lucky to find anything for components.
