Re: Advice wanted on rifle calibers
Flat to what range? Once you get above 3400 fps, point blank range trajectory changes very little.
The shorter your barrel, the less it is subject to barrel harmonics (whip) meaning the easier it will be to develop consistent accurate loads. The longer your barrel is, the faster your bullet will fly. Always a give and take. Difference in velocity will run about 25-50 fps per inch depending on load. If you want to maximize accuracy and velocity potential, get a long heavy barrel.
I.e, I had the choice to finish my Light Varmint S porter contour 6-284 to 27". I opted for 26" for accuracy sake and gave up probably 35 fps.
You will never know how much it has cost my generation to preserve your freedom. I hope you make good use of it.
~ John Quincy Adams