Ive worked it out, the best AMS system vs AMM swarms is (drumroll PLEASE!): Shields (surprise
)
how I got to this conclusion (my math may be wrong a bit but meh)->
Gauss:
,75 HS Gauss is 8 shots at 12,5% = 1hit -> in a max speed turret (100km/s) its 4,08 HS for 4 hits
since a missile travels at 290km that's a 1/3 hit chance +100% tracking time bonus -> 1/1,5
1/1,5 * 4 = 2,6 potential missile kills
2,6 * 9(damage per missile) = 23. 4 damage avoided
23. 4 / 4 = 5,8 damage avoidance per HS
shields (once charged) have 10hp per HS
ditto
*this assumes that the enemy is lobbing all their LR AMMS at you in single slow reloading volleys
*in case where enemy is using real missiles - other rules apply
*in case where enemy is lobbing a continuous stream of missile fire 1hs point defense per 1-3 shields is your best
TL|DR : shield are your friend