The Nikon Omega seems to be designed around a very hot load(250 gr bullet), from a 28" barrel. I wonder if this scope will still be effective with a load perhaps 10-15% lighter out of a 26" barrel, and a bullet around 290-300gr?
The scope graduations will just be off. This is the price to pay for a graduated scope. If you are going to depart significantly from the ballistics built into the scope, you may want to look at other options, like a mil-dot scope where you can learn the exact range each dot is accurate for, or even a tactical scope where you can dial in the range for any load on any gun.
Personally I doubt that all rifles will shoot so close that you can depend on the range listed with the scope. I have set mine up with the Burris Ballistic Plex scopes which is similar to the Omega but has cross dots kind of like the omega circles. There is another scope with different size circles that can be used as a range finder but it is way more expensive. I think you will just have to pick what kind of scope you like and shoot your rifle a lot to determine where it will hit with the loads you pick. I think with muzzleloaders there is just too much variation in how we load and shoot to rely on the charts.
The only way to see is to shoot it and see where the circles really are with your load, then write it down and tape it to your scope/stock. You can adjust your load a little if its close, but be sure not to sacrifice accuracy for nice round numbers.
If you want a Nikon - instead of the Omega - maybe look at the pro-staff with ballastic compensating reticule - far leass exspensive and designed for a regular rifle so that you may shoot any load you want then work out the point projections...
Personally i would suggest you go with the Bushnell Elite 3200 with Ballistic Reticule. It is a graduated reticule for windage and elevation. The optics are outstanding and the rain guard lens are worth a ton... very little use of scope covers needed.... + fast focus eye piece
I have a Nikon Omega mounted on TC Omega shooting 120gr 777 and 250 g Shock Wave all you have to do is zero at 100 and then shoot the different distances and make notes where on recticle you need to hold, for your paticular load it may be bottom of 200 yard circle instead of center. After a little shooting you will know where to aim at all distances and will love the Omega scope...
There is one more scope you might want to look at. It is made by Leatherwood and is set up the same as the Omega scope but is a 3x9 and has cross-hairs instead of the circles. It has Toby Bridges name on it. I bought one for my encore but didn't get to try it out yet.
__________________
I AIN'T AS GOOD AS I ONCE WAS, BUT I AM AS GOOD ONCE AS I EVER WAS
Nikon Omega question
