Le_Garcon t1_iv0qxl7 wrote

That's a myth, Mattel never made M16 parts.

It was a rumor started by soldiers who (understandably) didn't like the early M16 models and said they were toy guns or had furniture made by Mattel.

A persistent one too, you can find vets who swear up and down their rifle had Mattel markings on it but Mattel never had such a contract and there's no evidence of them ever making parts.