Shaun said:
Usually full auto is a pretty ineffective way to hit a target due to the recoil. DW kind of takes a perverse view of this and it very rarely makes sense not to use full auto if you have the option to. The only reason I can think of to fire my bolter on anything other than full auto is ammo conservation and a very small change in the odds of a jam.
Move and Fire: If I understand the rules right, you get a -10 penalty without the usual +20 bonus when using full auto while moving. When using Semi-Auto, you don't suffer the -10 so your BS is 10 higher. A vialble option if you suffer penalties of any kind.
Pretty extreme but we got good results.