I'd be for betting if you'd of slowed it down 100 fps it would of perked really well.
Regarding barrel life, I've been using various big 7's for 4 decades. My fav is the 7 Mashburn Super. For life I've been getting 2500 rounds give or take. Usually around 1700 rounds I start chasing the lands a bit, then around 2500 accuracy begins to go and fouling becomes a PIA so it becomes time to rebarrel.
These big 7's will take a heck of a lot more rounds than most people give them credit for.
Just my experience, take it for what it's worth.