How high accuracy do you need to stop missing hits with unload? I currently have 402 rating in accuracy (99.60%) and i miss around 15% of unload.
you would need 100% to be save that each of you main hand shots will hit the target. However, Offhand attacks inherit a 33% penalty to the hitchance. Thats why some of the smaller hit of rapid shots and unload will always miss the target!
15% is just the standard miss chance when mainhand and offhand hits are calculated together, nothing to worry about =)
Overall ppl put to much emphasis on dps. Don't ignore dps but also look at total dmg in a fight and dmg taken tabs. Before maint last was running a quick raid and I only looked at the last parse but I beat the biggest sniper in guild in total dmg but he beat me on dps.
looking at a few different things can give context. Can be better to take less dmg while putting great dmg on a boss for obvious reasons.