For me, the whole point of this thread is about a configuration that I think is cool to be used on a Mac style RR that can be shot in full auto. Has it been done before? Certainly there has been some custom stuff done for a Mac style RR. But there is the rub. I have had several custom projects done. It is so hard to find someone to do a quality job on a custom design that isn't so backed up with work that is already sitting at their shop waiting to be done. And for such custom exspect to pay a premium price.
Is there an integral ported barrel/suppressor combination off the shelf upper for a Mac style RR commercially available? Sort of, but would be very expensive. Could a can be put on a 9mm upper and shot with 147 or higher subsonic ammo? Certainly, but I have only seen a picture of an integral suppressed Mac style upper. I have never seen nor shot such an upper in real life. I would like to. Is there commercially available options available for other transferables? Yes, but those other machineguns are $30,000 to $55,000. When those other transferable machineguns are considered, a $3,000 or $4,000 accessory doesn't seem so pricey.
Scott