Just tossing this in here, but IIRC Remington made a model of their 7600 that used AR style magazines. I think they called it the 7615.
Interesting gun and of most use in places where a semi auto AR may not be a wise or legal idea while also maintaining the ability to have decent magazine capacity or just more commonality with an AR platform. It was something of a homologation of the 870 shotgun and AR-15. They billed the police version as having commonality with the manual of arms of the 870 while giving the officer a more accurate longer range weapon than the shotgun. To my knowledge they aren't still making it.
Yup... found it.