I am looking to shoot the Lee 340 grain rnfp in the 1100-1200fps range. I have several rifle and pistol powders, including IMR 4759 and Accurate 5477 to choose from. I have seen a reference to using Alliant Unique, foggy on the details? Our rifle is a Browning Hi-wall. Mostly plan to shoot with iron sights out to 100 yards. THANKS in advance for your replies, hc18flyer