March 7, 2025

The 45-70 and ballistics

It all depends on bullet weight and muzzle velocity. Here is some data for "subsonic" 410 grain Hornady 
  0 yards  1075 fps -1.5 inch
100 yards  992 fps  +17 inch
200 yards  930 fps  0 inch
300 yards  879 fps  -57.1 inch
400 yards  835 fps  -159.2 inch
500 yards  796 fps  -311.4 inch
So, how many MOA is that at 500 yards?
We have 26 feet of drop at 1500 feet.
We want atan ( 0.01733 ) = 0.99 degrees = 60 MOA

Figure to double that (to 52 feet) at 1000 yards, more or less. (which would still be 60 MOA).

Compare the drop for a 6.5 Creedmoor at 500 yards which is -49.6 inches (-9.5 MOA)

They say the Quigley shoot in Montana is done at 800 yards.

a fellow says (for 1000 yards) -- "From a 200 yard setting go up 120 minutes of elevation With a 500 gr bullet going around 1080 fps will get you on paper."

Also from the second discussion linked above, a fellow says that a 540 grain bullet will get to 700 yards and at about 800 fps will not have enough rotational speed to stay stable. He says launching it at 1200 fps will give much better chances of getting to 1000 yards.

MVA sight

I started thinking about this when I looked at the MVA Soule sight, which they say offers 289 MOA. But of course that depends on the barrel length (rear to front sight distance). They say this sight is 4.93 tall. My Marlin 1895 has a 25 inch barrel, so figure 4 inches over 25 inches. That is 9 degrees or 540 MOA -- so I don't understand their claim of 289 MOA.

Note that their Soule long range $513 and sharps long range $395 give the same elevation MOA. The important difference is the Soule has windage adjustment.

In closing, note that 1 mile is 1760 yards. They now sell an XLR sight that is 6.18 tall and gives 414 MOA.

Feedback? Questions? Drop me a line!

Tom's Computer Info / tom@mmto.org