I'm going to suggest the Vortex Viper PST
6-24X50. I also suggest that you get a second focal plane reticle. My reasoning is that for targets out at nearly 1K the reticle becomes too thick in the FFP scopes. I happen to have a Viper PST 6-24X50 FFP MOA and I am getting a second scope with SFP just for that reason. I love the scope and I love the FFP out to about 600 yds. After that I long for the SFP (so I am getting one). Yes, you can hit a steel plate at 1K with a 10X but if you really want to see what you are hitting and don't have 20/10 vision you will want the extra magnification. It sounds like you won't be shooting closer than 100 yds which is where the lower power would be good for the low end. So, for 100 - 1000 I suggest the 6-24X50Viper PST is a great scope and power selection.