my buddy does have a 45-70 marlin ( non ported ) and he uses win 300gr. JHP. it does kick almost like the 450marlin but less sharpness to it.
i knew she was gonna kick and i will be only using it in the future on bear hunts. i would like to see how she does on black bear in maine. the real problem i did have before i decided to go with a peep was looking for a good scope with long eye relief and one that would not loose it's zero.