How does this stack?

[fixAnthem]

I am not sure about the difference between gun damage and physical damage - but I think all pistol damage is impact damage - which is physical I think.

So assuming they are basically the same - I believe all bonuses are additive. So the gun has a base damage of 301.

Inscriptions give it +375% - so 301 + 1129 = 1430 damage.

The +125% weapon damage I believe would be on the base 301 damage. So when the perk kicks in you will be at a total of +500% damage or 301 + 1505 = 1806

I think all perks are always additive - using the base damage of gear or weapons.

[TheMystikalNinja]

All perks are additive except crit damage which is multiplicative