Free: Contests & Raffles.
A shortcut I found is to search for premium commercial loads with the same bullet. I have a sample size of one caliber, but they all seemed to be box rated at nearly the same velocity. I bumped my old load up so I was getting an actual chrono velocity that matched the stated box velocities and bingo, group size shrunk as did velocity variations. I don't know if I missed that in my original workup, didn't have a large enough sample size or what, but a half dozen range trips has confirmed it.I think a lot of the manufacturers have found velocities that nearly universally shoot well for most hunting bullets. If you can find some it might be a good place to start. Of course you likely don't know what powder they are using but the internet is good at showing what powders reloaders favor as known to work well.
Thanks Jrebel. I'm all over the clean barrel. I learned that lesson as well when I made the switch over in my 7mm Rem Mag. I've been shooting the 145 LRX in that one for a few years now with exceptional performance. I've tried the 120 gr Barnes TTSX in the 7mm-08, with subpar performance. Maybe with more tinkering I could get it dialed in better, but I shot a lot of variations with basically the same performance across the board. The rifle is a Remington 700 Mountain Rifle, LSS. They have a good following, but man it's finicky little sucker.