Patrick, #5MK1 is dead on. When comparing the two, it's best to find a No.4 and a No.5 that are in like/similar condition. My FMP No.5 is in good+ condition and comparing it to a similar No.4 shows that 100 yards can be very competitive between the two. Moving out to 300 yards the No.4 begins to walk away from the No.5 printing about one MOA better using UMC 174 gr ammo. More practice with the No.5 would help.

This is actually typical when comparing a rifile to a carbine. I hunt with a Remington 660 (carbine) and when it's compared to a Remington 700 (rifle) it'll fall behind the 700 as the range increases.

Brad