You see these kind of adverts all the time you know the ones  “For sale custom M4 ! Real magpul iron sights/foregrip/sling plate , custom paint job , upgraded spring !” umm no it’s not , bolting bits on your gun , changing the spring and spraying it with some paint does NOT A custom gun make . In my book if it’s a gun that anyone can re-create just by going on the internet for ten minutes dropping some dosh and then waiting for the postman to deliver said bits’n’bobs then sorry but tha