It's feasible to start with a 40 Toughness if the maximum is rolled at Rank 1 and if wearing Guard Flak Armor we now have a total soak of 8.
I just had to imagine a Commissar trying to execute a Guardsman. 1d10+5 vs TB4 + 20 Wounds
(let's assume the Commissar had the poor guy/gal take off their helmet first)
*BLAM* Die *BLAM* you *BLAM* worthless *BLAM* traitor *BLAM* *reloads* *BLAM* ...