will be breaking in a new barrel and developing a load for a 12FT/R being re barreled in Remington 260 in the next week or two. Just curious as to what you guys feel is the best range for LR load development. I have a choice of 100,200, 300, 600 and 800 yards. The gun will be primarily shot at 600 and 800.

My thoughts are:

100 - fewest external variables such as wind and shooter variables, but a lot of things can happen to a bullet between 100 and 800
200 - what I am leaning towards, wind is pretty predictable on those targets
300 - a good compromise
600 and 800 - too many externals to know whether it was the load, the shooting technique, or the wind

pretty much decided on either 200 or 300. Range is pretty calm in early mornings but I have to fight sun in the scope because the range faces NE , afternoons tend to be windy. 200 has pretty predictable wind, 300 berm and target is fairly protected but if wind is from south (right to left) you get a swirl effect in the last 100 yards.