I grew up deer hunting with my dad's 1951 Model 94 in .30-30. It went to my older brother. Several years ago I acquired my own 1950s era Model 94. It shot fine with 150gr Core-Lokts, but eventually I realized that I just can't see the front sight in the notch of the buckhorn sight as well as I used to be able to. So I put a tang-mounted peep sight on it. And I could see the front sight again. However. It didn't take long to realize that where the tang-mounted sight was situated is right where my thumb wants to wrap over the stock while holding the lever in the closed position.

So, this last fall I acquired and mounted a Williams FP receiver sight. Subsequent to that, I found a deal on almost 300 160gr Hornady FTX bullets. Running them over 28.5gr of IMR3031 they group well at 25 yards. The problem though, is that at 100 yards, with the rear sight as far down as possible, the bullets are launching over the top of the target frame. At least 24" high. Possibly more.

The current front sight is .225" tall. The replacement front sights available are .290", .312", .343", .375", .410" and .450". Based on the formula of "Sight adjustment" = "Length of sight radius" x "Offset" / "Range to target in inches", I think I need, at a minimum, a .375" replacement sight.

.150" increase (.375" new - .225" current) = 22.5" (distance between front & rear sights) x 24" offset / 3600 (100 yards in inches).

I think I should order a .450" replacement sight, since .375 is a minimum, and would only be correct if my offset is 24" and the rear sight is all the way down.

Concur? Disagree?

I don't know if you found your answer or not, but I will try to help. You say your front sight is .225 tall. I am guessing you measured from the top of the ramp. Sights are measured from the bottom of the dovetail, so yours is probably .375. My son and I have the same set up on our 94s. A .375 works for me, but my sons hit high and required a .420. I would try the .410 or .450.