Today was final zeroing with hunting ammo from the bench. For this trip I've selected Buffalo Bore's 350 grain JFN. I contacted Buffalo Bore to get their advice and Mr. Sundles himself got back to me within 48 hours. The choice was pretty much between their 350 gr JFN penetrator, the 430 gr hard cast, and a 500 gr FMJ-FN. Normally I like to shoot something heavy for caliber, but in this case I wanted a lighter bullet with slightly better ballistics based on the 45-70 (the drop on the 350 is a bit of a flatter rainbow than the 430) and I wanted something that would be more versatile for hog hunting after the grizz trip. Mr. Sundles personally has used the 350 gr on grizzlies with good effects and there are lots of positive reviews so I opted for the lighter round. It should still get 4' of penetration (vs. 5-6' in the heavier rounds).
My Hornady (325 gr @ 2050 FPS box placard for 3032 ft/lbs) was printing about 5" high at 100 yards: right where I wanted it, basically. It was a hot day so I figured the POI will come down 1-2" on Kodiak at 30 degrees Fahrenheit. The Buffalo Bore (350 gr @ 2060 FPS for 3426 ft/lbs) printed a whopping 13" high at 100 yards. This was confirmed with solid three shot groups from each round at the bench, with each group being about the size of a silver dollar (most of the holes were touching; the Hornady had a bit of lateral stringing from bad trigger control and the Buffalo Bore had one shot that was about 1" high and right, my fault again). But with groups the size I was making I felt comfortable making sight adjustments.
I expected the Buffalo Bore to be a bit higher but not that high. After all, the Hornady's much vaunted "Leverolution" bullet design is supposed to create flatter trajectories, right? However, when I dug into the Hornady velocity numbers, they assume a 24" barrel. The Buffalo Bore number is for an 18.5" barrel, like my 1895GS. So I suspect that the Hornady is really going at least 200 FPS slower than the Buffalo Bore. Looks like muzzle velocity, not magic polymer spitzer bullet design, is still the key, at least within 100 yards or so.
In any event, we got the Leupold dialed in quickly. I cranked it down 34 clicks (34 x 0.25" 1/4 MOA adjustments = 8.5") and the Buffalo Bore went right where it needed. Everything was printing about 0.5 MOA left so I cranked it over two clicks right, but that overcorrected, so I settled back one click to the left to split the difference. Bam, right where it needs to be.
At this point I feel really comfortable with the optic out to 200 yards. I could probably be effective further but without having shot on a known distance range out to those ranges it is hard to just trust the ballistics table, especially for something like the 45-70 which is really more of a rainbow trajectory. I feel comfortable with the irons out to 100 yards, just based on the larger groups I was getting with the huge aperture ghost ring sight from field shooting positions. Still, if it comes to using the back up irons or wading into the alders after a bear I think the irons will do just fine.
I am really impressed with the rifle/optic combination. The rifle was shooting around 1 MOA from the bench. Maybe even sub-MOA on some groups. To be fair I had Wild West Guns in Anchorage do some custom work on the rifle (bead blasting, trigger job, lever job), but I wouldn't expect that to really do much for accuracy so this is just Marlin quality. If I do my part, I feel confident that this rifle/load/optic will do its part.
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