Looking at getting a new rifle and came across the 2 newer 6.5 cartridges. 6.5 PRC and 6.5 RPM. At first blush it looks like they are pretty much identical on ballistics but the cost of ammo is drastically different between the two. Any reason for this other than one is Weatherby so it automatically costs more? Just curious if there’s a benefit to buying one over the other.