Well, I have a .50 Beo. The round is very similar, and I can say that with that particular round and a 16" bbl., that 100m is about right, 200m is really pushing it. It falls like a rock at that range.
But at very close range, it made mincemeat out of an Interceptor vest we tested in the army --we looked at it for the unit as a roadblock tool to disable cars, to blow locks off (we used slugs at the time) and other work. But the Stryker and the way they were used changed that and a remote fired M2 just works better on cars. But that thing WILL stop one fast if you hit the intake. Shatters Nissans like glass.
I would definitely not want too much magnification, I say that a lot, but definitely not with that baby. A red dot was pretty nice though, and your irons are too.
Nice rifle. It should beat the .50 Beo for sure in velocity with a barrel like that, the Beo rifle is similar to the .500 handgun in power. The lighter bullets are just smoking, the heavier ones are like sledgehammers. Good thing you load! I couldn't shoot like I want if I didn't.