Building an MP5 clone pistol from a flat 80%__legality

[hnakieb]

Hi

Does anyone know or can direct me to the right place about

Building an MP5 pistol using a flat reciver ?
I heard both yes and no. If i bild it before the 21st and engrave it with the proper information and register it next year as an assault weapon is it ok?

[supertrooper]

your have to build it as a single shot pistol.if you want to register it as a RAW you need to build it by the 31st