ammo selection. fun.
I own both but I much more enjoy blasting 400 rounds of 223 vs x39. I also don't think it's cool to have to water hose the corrosive shit out of a rifle right after the range (545)
Then don't shoot corrosive ammo....
On a side note, do you think even 90% of the AK74S in combat get cleaned after every engagment? They do just fine for a very long time.....
Same thing goes for all those Mosin everyone loves that spent their entire lives shooting corrosive stuff...