Did you stay with the same weight bullet in the solid alloy bullets or did you go down one weight size? I personally use 165gr in 30 cal in my 30-06s. Should I then plan on going down to 150gr bullets in 30 cal for my 30-06s if I was looking for a similar length bullet with similar performance on game?
I use 150 gr. TTSX bullets in my 300 SWM for deer and elk, and that's plenty coming out of this gun at a little over 3000 FPS. All the copper bullets are noted for extreme penetration, so you don't need the weight to achieve that. Also, I like the idea of a faster bullet. I believe the 165 grainers would be great, but, honestly, I don't think the 180 gr. will give any better performance.