I have Marlin 1895s in 18.5- and 24-inch barrels. I use H322 and IMR 3031 powders with CCI Large Rifle primers. While I have Remington and Winchester brass also, I will be using only Starline 45-70 brass for this query.

I have acquired a supply of Remington 405-grain JFP bullets. I also have a small supply of Alaska Bullet Works 405-grain SPFN. I can work up loads where these bullets will have essentially identical muzzle velocities. My hunting area's maximum range, probably mine also, is 150 yards.

How closely will trajectories of these bullets correspond? ABW bullets are a dollar each while Remingtons are about 35¢ each. If feasible, I'd like to practice with Remingtons and hunt ABWs.

I believe point of impact, and accuracy will be a bigger deal than the tiny difference in trajectory. Seating and crimping in separate operations (a shameless Lee Factory Crimp die plug) will make these critical operations easier and less frustrating. With the different brass and bullets you mention. It will be money well spent.

While their trajectory might not be that far off, their points of impact could be very far apart.

I recommend you develop loads with both bullets, side by side, to not only check accuracy, but how close together they shoot.