I have a CVA Staghorn Magnum which I believe is the next one on the inline chain, under yours. This CVA will shoot 245 grain powerbelt copper HP with 90 grains of Goex 2f excellent. It will also shoot the 348 grain pure lead HP with 90 grains of Goex 2f excellent. There are a number of different sabots like the 240 grain T/C Mag Express XTP that is shoots excellent.

What I am getting at is your Eclipse is a great rifle. Anyone that owns or owned one will never tell you they are not accurate. Your concern about the barrel pressure issues is a matter of personal choice. I shoot my Staghorn all the time. The one thing I do not do is put large charges in it. I use common sense and besides, the rifle does not like large charges.

I personally think the Eclipse will work just fine for you. I will say that if you're worried about the "spanish barrel" then maybe for your own piece of mind sell the thing and use the profits on a different rifle.

Personally the .54 plains rifle might be a little heavy, but it is more then able to handle the job too. I considered the GPR but instead bought a Trade Rifle. I really like the rifle....