I know that this was posted earlier, but even though HK calls it a M110A1, I don't think it's a pure M110A1. It uses the upper, but several things are different from the M110A1/E1.
Handguard looks different
It seems to be using a G28 spec B&T suppressor instead of the OSS suppressor used on the M110A1/E1
It's using HK BUIS instead of the Troy canted ones.
Stock might be different.
Is this some kind of franken-rifle that HK are saying is a M110A1 due to it's use of that pattern of upper? Or is it a HK R&D project that they're for now claiming is a M110A1? Lightweight evo of the G28? Or a PIP HK417P?