Put them both at 80 range and the 82mm will deal more damage because it hits more accurately and more often. The reason the 120 is better more often is the range more than anything.
You can test both mortar firing at 80 range into the FOW in cheat MOD and let come back with results.
And "hits accurately" does not mean much if does less per hit.
No one is saying the 120mm is bad. But in the ranges it can be used the higher dps of the Lil guy is simply better. I guess it comes down to preference. Now, if you will, this is extremely off topic and has gone on long enough.
Yes it has for far to long because certain people are obsessed with trying to correct me...