I happen to be blessed with a job that pays me to shoot a tactical rifle. Our department uses the Remington Police LTR as we don't need the added barrel length in an urban shooting situation. We use the Leupold Mark 4 3.5-10x40 LR/T M1 milldot scope mounted with the Mark 4 rings. Some guys like more power or think it is needed but this setup will easily engage targets out to and beyond 800 meters. These scopes have proven to be very durable, provide a clear sight picture and a non critical eye relief. When looking at the Mark 4 it will help you to know that the M1 has 1/4" MOA windage and elevation adjustments while the M3 has 1/2" MOA windage and 1" MOA elevation adjustments. I prefer a variable power scope to a fixed as I feel I have more options at different distances with the variables. Some agencies do employ fixed power scopes in the 10 power range to engage targets to a 1000 meters and beyond. Hope this might help you out. If you need anymore info let me know and I'll try and help. Keep us posted on the Tikka Tactical as I was thinking of buying one for a home project.