The barrel is a stainless Sig Saur and is supposed to be quite good. We have a range not far away that offers up to 800m, so it would be fun giving that a go.
My friend Jon has already mentioned bullet seating depths, I'll let him help me experiment with that. It is mag fed, currently a big, daft 30 round one that just gets in the way, I have a ten round on order. I don't know if they'll accept the same lengths?

Lots of exciting testing to come