My solution is to go back to Rogue Trader stats and make "Astartes" a property that adds +1 Damage, +1 Pen, and +10m range to non-pistols.
This makes a standard bolter 1d10+6, pen 5, tearing.
One thing to remember is tearing makes your mean roll an 8, so 50% or more of hits will do 14 damage pen 5. 75% of hits roll at least 6, so 12 damage pen 5. This is enough for a damaging hit against the average space marine.
So yes, at an average of 2.45 penetrating damage per hit it may take 5-7 rounds to disable a chaos space marine. I don't actually think that is wrong, it actually favors the players and their additional talents and hopefully superior tactics. Under the current stats you average ~5 more damage per hit meaning 4 hits will disable a space marine. While this may sound fine to some people, I, as a player, would rather not be downed by a single lucky hit from a chaos space marine.
Of course, any marine vs marine fight is likely to include kraken rounds, which at 5 req points I would bring with any tac marine most of the time. This ups the average damage per hit to 5.16 using my modified statistics. So 6 shots can take down a marine. Under the current stats a marine can be disabled in 3 hits, which a chaos marine on full auto can do that fairly regularly.
All of the above numbers ignore righteous fury, which a marine can trigger 19% of the time using my stats, and 27% of the time using the normal stats.
To be honest, other than the weapon damages, I'm very happy with Deathwatch. I'm looking forward to future expansions and many years of 40k rpg gaming.
