Ok I am using numbers from the New Vegas wiki for this one since I don't have access to playing the game right now, but I think there is something wrong with the way the DT and DAM calculations are working. I went to fight the Van Graffes (This is the most specific example I can give because it was really making me mad.) They all have Combat armor that has a DT of 15 I was using Cowboy Repeater with a few mods and the DAM = 32. Now maybe I am misunderstanding how everything works, but 32 is much higher than 15 and when I was firing at them the little shield was showing up saying that their DT was absorbing my shots and I was barely doing any damage. So I switch to my other gun I had with me the Hunting Rifle ~ DAM = 45 again much higher than what their DT would be and again the same issue little shield showing absorption and very little health damage. So I decide to switch again to my Lever-action Shotgun ~ DAM = 50.4 and I also have the "Shotgun Surgeon" Perk allowing me to ignore an extra 10 points of DT I think it was?? Again I fire at them and even at close range (within 5-10 feet) little shield showing absorption and extremely little health loss. Like I said I don't have the game right in front of me so the numbers might be a little off since they are from the wiki. I reach all weapon skill and STR requirements. So I get fed up trying to shoot them I take out my Fire Axe ~ DAM = 55 run up to them and I start doing damage to them instantly nice and easily and the power attacks work even better. WTF!?!?

This has happened to me with numerous other occasions and it seems like something maybe wasn't coded right? Another thing I have noticed is with the Anti-Material Gun. When I go into my pipboy and I have some other weapon equipped, if I hover the cursor next to the Anti-Mat Gun it's DAM says something along the lines of 167 or something in that area. So I equip the gun and all of a sudden the DAM goes down to 111-112 <---somewhere around there) again I meet the skill and STR requirements.
Also with AP bullets it seems like the bonus DAM is calculated after the initial hit? Instead of being calculated into the shot itself if you understand what I am saying. Like if the shot would originally be absorbed it still gets absorbed instead of actually breaking through the armor.

Maybe I am just not understanding the way the system works, but from what the game describes on the info-loading screens and also the instruction book something isn't working right IMO.

What ammo were you using in the cowboy repeater? or the hunting rifle? if your using hollow points that easily explain your problem. Also with out living anatomy you can't be sure what their actually DT is based on the equipment you salvage.


As for the shotgun I can explain fairly easily

A shotgun divides the damage among 7 pellets. Fifty divided by 7 is well about 7. Each pellet must face DT individually So with shotgun surgeon against a DT of 15 its effectively 5. So each pellet deals 2 points of damage. Which basically means the perk did nothing as your at least going to get 20% of the damage minimum anyway. When using a shotgun against armor use slug rounds as all the damage is in one big slug instead of divided among a spray of pellets.

In the Repeater and the Hunting Rifle I am pretty sure I was using JSP hand-load rounds in both, not entirely sure on the repeater since I can't remember if there is JSP .357 rounds, it definitely was not HP rounds in either though. As for the shotgun I only use slug rounds, that is all I craft for it and all buckshot I breakdown and remake into slug.

How does DPS factor in then if what you say is true about the 7 only doing 2 points of damage after the (15 - 10 = 5 surgeon perk). With the Lever-action Shotgun w/ slug rounds the DAM ≈ 50 and the DPS ≈ 90 (I think), what's the point of DPS if that has nothing to do with the damage dealt?

DPS is the damage per second not the damage vs armor. The pip boy doesn't calculate your damage vs armor.

the pipboy shows both DAM and DPS. if the DPS is 90 and you break through DT with the DAM how does that calculate is what I am trying to ask.

I don't think I'm quite clear, the DPS is simply the damage based on the rate of fire per second.
The avenger mini gun can get off around 30 rounds a second which is why its DPS can be 350 while its DAM is only 12.

If your firing at an unarmored target you will turn it into swiss cheese fairly quickly or if your using armor piercing rounds and completely negate the armor. If however the target has nine DT remaining the effective DAM is only 3. 3x30=90 which would be the effective DPS against that target. The Pip boy however can't show you the damage vs armor as different targets have different levels of armor.

Ok so that makes sense now, but I am still confused about my DT, it seems as though Fire Gecko's, Golden Gecko's, Giant Rats, and Deathclaws do really high damage to me regardless of armor being worn. I understand the Deathclaws, but why the others. I want to say that I am playing on very hard so obviously enemies are going to be tougher regardless, so I'm trying to figure out in which way it does this does it up enemies DAM while lowering mine, or does it give them more health, combination of both?

And like I said I was using Slug rounds which would give me effectively a single shot from the shotgun with ≈ 50-55 DAM and was doing nearly no health damage to the van graffe's, but when I hacked at them with my fire axe that has ≈ 50-55 DAM as well it was very clearly showing effectiveness against their health (I wasn't just swinging madly either I was probably swinging around the same speed I could fire the shotgun).

Also do you know what might be going on with the Anti-Mat Gun?

The Anti-Mat gun requires a SP of 100 Gun, so if your short of that -very possibly - I'm sure you will not meet the full DAM potential. Your gun also requires to be above the repair threshold to maintain it's maximum DAM potential. Sources dictate that if your weapon has a condition of 75-100 your weapon will achieve full stats available, if you are less than 75 condition your weapon DAM degrades at a rate of 0.67% per PT of Condition less than 75. Example: Gun A has Potential 100 and you meet all STR/Gun requirements but your condition of the gun is 46 then it degrades as such: 0.67 x (75-46) = 0.67x29 so the gun actually outputs 100-19.43=80.57 Max at condition 46.

The other questions I do not follow with great clarity so I will hope Lord Vukodlak can assist you there.

Reno

The gun is at 100% condition, and as I said I meet both the 100 guns requirement and the STR requirement. When I roll the cursor next to the Anti-Mat with another gun equipped at the time the Anti-Mat says ≈ 167 DAM if I remember correctly and the second I equip it the DAM moves down to ≈ 110-112 I can post a video of this happening tomorrow if my explanation isn't cutting it.