Bypass armor from criticals

[Puncher]

Does this type of critical ignore everything?(including drugs and perks like toughness or natural racial resistances?)
For example im at St. Louis mission (insane difficulty) and my melee char using drugs(2 psycho and enviroment armor gives me 140% damage resistance 100 from drugs and 40 from armor) and Supermutants do 0 damage to me as regular bursts with their M249 Saw.But once in a while they do bypass armor (from crits) and hit me 140+ damage and i have 120 hp so basically i die from 1 shot with full health.I dont even dare to go near M2 browning muties cause this is suicide.
As pure melee squad i find impossible to make this mission really and this is because of this bypass armor criticals.

 

[Puncher]

Actually doing the rest of campaign from St Luis till the end as melee squad on insane-tough guy is not so hard.But for this you need Mother (deathclaw recruit) .This deathclaw is incredible(at level 10 she has ~ 200 hp) he has tons of hp and can take even 1 burst of bypass critical of any big gun excluding M2 browning .But best thing about Mother is that this mutants with their big guns dont even have the chance to shot if Mother reach as melee range in sneak mod.And this is because her hits are all knockdown wich wastes ap from AI.
Also i discovered a bug wich helps tons alot as melee fighter(maybe its abit over the top making to easy).If u use unarmed and aim for left leg and in case of a critical hit you have a good chance to cause huge damage(some even astronomical damage).This works best with better criticals perk (can work even with heavy handed or without better criticals but much less astronomical hits so i dont recommend using heavy handed at all since it reduces chance for nasty damage) .I tried using guns to check if this work for range weapons but it seems no,it works only for melee.