Re: 284 Win. and RL 17
Unless you have a very long barrel, I don't see you getting 3000 FPS with the 180s. RL17 is a very high velocity powder for sure but it is not that fast.
I have run 168 grain bullets in the 308 at 2950 in a 26" barrel with RL17. Pressure signs were also starting to show up. Now I realize the 284 case has more volume than the 308 but does not mean equal bullet weight will go faster in the 284 case. Equal bullet weight and equal barrel length, they have about the same velocity potential. All else being equal, larger bores have higher velocity capabilities. The added volume of the 284 gets offset by the bore diameter. If you look at the Hodgdon's reloading center you will find the for the 168 grain bullets in equal barrel lengths, the 284's top load (2830 FPS) is only 2 FPS faster than the 308's top load of 2828 FPS. Once you get to the 175 grain bullets the 308 is actually 30 FPS faster than the 284's top load. You could probably get close to 3000 FPS with the 168 but not the 180s. Not trying to say the 308 is better, just using this to show a more apples to apples comparison for my real world experience with RL17. If 2950 FPS was getting too hot for my 168/308 load, 3000 FPS for a 168/284 load is probably going to be too hot. The 180's are going to be on fire.
There was a guy at 6mmbr that was getting 3000 out of this combo but he was usuing a 31-1/2" barrel to do it. He also was using a '5C' barrel which some claim to generate less friction. Also, many target shooters over there run very hot loads at that. A normal hutning rifle is not going to safely push the 180's to 3000 FPS.
Long range shooting is a process that ends with a result. Once you start to focus on the result (where the shot goes, how big the group is, what your buck will score, what your match score is, what place you are in...) then you loose the capacity to focus on the process.