Degradation of the weapons?

https://www.gog.com/forum/fallout_london/after_reading_combat_coaster_card_all_weapon_damage_gets_displayed_as_halfed_in_my_inventory

I already have also done a topic about that. It´s the Card "Combat Coaster" in "The Hound" pub with the double headed dog on it.
After realizing what happened i stepped back through all savegames and finally found it - lost about 2 hours with that as i started playing from that point before picking up that card. No idea yet how to remove the perk from it with the console, so i can only suggest that you also load a savegame previous to picking it up.

Thanks, mate! Now I just got to find out how to remove that via console or I will lose many hours of exploration. :P

wait, what?! This is why it's been like swimming uphill all the time!? Haha, and here I started to think the extra ammo finding perk seemed mandatory.

My save is like, 8-10 hours after the Hound Pub, probably going to need some console commands for this.

Inside the Fallout London installation folder is a data subfolder, inside this folder are 2 .txt files named folon_sperks - both filled with id´s but no information what does what. I did not fully try it yet but i bet one of those in these files is the related one.

SOLUTION
You can remove the coster and the perk via console and once you select a weapon in the inventory its damage resets to full.

To remove the coaster:
player.removeitem 0727D392

To remove the perk "Combat Beer Mat"
player.removeperk 0727E475

Once the perk has been fixed you can re-add the coaster:
player.additem 0727D392

If the IDs dont match or you are looking for another bugged perk: Use "help X 0" where X is the word you are searching for to search the in-game database for IDs.

Thanks to LirdNighthawk for putting me on the right track!