ORIGINAL: bronko22000
My Marlin likes the loading of 51 gr of H4198 behind the Speer 300 gr HP (#8900). I haven't yet used this load for deer because the areas I hunt I can get shots farther than I care to guesstimate the trajectory of the old .45-70 and usually take my .270 or 7mm-08. This load however has accounted for 3 black bear - one shot each and it really cleaned house. It should work fine for deer also and the recoil is less than a 12 ga 2 3/4" slug.
Bronk, I got some serious horsepower out of that load you got but started getting vertical stringing after 47gr. Other than that I get 1.5MOA out to 200 yards. Do you see any vertical stringing? Also is your barrel ballard or microgroove? mine is micro.