Lyman #17 for Model 94?

[jsimmons]

I have a Model 94 with a front ramp site.

Will a Lyman #17 fit on the site ramp? If so, which one is the most appropriate? I'm thinking it would probably be the AHB (0.404") or the AMI (0.494").

[marlinman93]

I'd just drift the existing sight out, and measure the with my dial calipers. If it's .375", then the #17 will fit. You'll want the shortest possible version, unless you've got a tang sight on the rear with enough adjustment to allow a higher front post.

[Griff]

I'd just drift the existing sight out, and measure the with my dial calipers. If it's .375", then the #17 will fit. You'll want the shortest possible version, unless you've got a tang sight on the rear with enough adjustment to allow a higher front post.

You want the new sight to be ¾" from the centre-line of the bore. That's from the bore to the cross hairs or top of the post.

[jsimmons]

I'd just drift the existing sight out, and measure the with my dial calipers. If it's .375", then the #17 will fit. You'll want the shortest possible version, unless you've got a tang sight on the rear with enough adjustment to allow a higher front post.

You want the new sight to be ¾" from the centre-line of the bore. That's from the bore to the cross hairs or top of the post.

It seems to me that measuring accurately from the center of the bore would be problematic, and that measuring the original sight's height (as described by marlinman) would be more accurate, as well as more appropriate since sight heights are specified that way. If I can't find a #17 that's exactly the right height, should I go to the next taller version?

I will have a tang sight - just trying to decide which one. Actually, I'd like to have a creedmore style vernier sight, simply cause they look neat (and I already have one on my Henry 22 that works real well).

[Griff]

A little high school arithmetic gets you the correct dimension. Measure the outside dimension of the barrel at the front sight. ½ of that is the centerline of the bore. Measure from the top of the barrel to the bottom of the dovetail in the ramp. Add those two numbers and subtract from .75 to get the sight height you need.

Just as tall scope mounts will increase the variance between line of sight and line of bore, so too will too tall of a sight. Thus, adding to the difference in line of sight to actual trajectory. Making adjustments for both short range and long range more extreme.

It's always preferable to have the line of sight as close the center-line of the bore as practicable. ¾" allows for adequate accurate sighting at the apex of the trajectory, while still allowing enough rear sight adjust with factory sights for longer range sight. I don't have a graph readily available to demonstrate, but... on my .30-30 say, that ¾" above the center of the bore allows me to have a rather large "zero" range, (where the bullet stays within a fairly narrow margin along my line of sight. I.e., the distance the bullet travels that it remains within, say 2" of the line of sight). The higher the front sight, the shorter that range will be.


As compared to a chart showing a sight height of 1-½":


Admittedly, the incremental difference is quite small, as even at 500 yards, there is only a 2.2" difference in line of sight vs trajectory. For precise shooting at unknown ranges, or if you're like me, not the best of range estimators, I want all the variable factors in my favor!

[marlinman93]

Calipers on the end of the barrel will give you barrel thickness, and simply add 1/2 the bore diameter to that. But I'm unsure how you decided on the 3/4" being some sort of standard? Is this for that particular model with a standard rear sight? I have numerous guns with large enough diameter barrels that 3/4" would never work as a standard dimension. If getting the sight closer to the bore is important, then why not shorter than 3/4"? Using that theory, I'd go as short as possible for the front sight. And since his plan is to install a tang sight, then 3/4" is even more random. I have a Hepburn with an old globe sight on the front from the 1800's. The barrel is 1.125" at the crown, and the sight sits @ 1/2" above the barrel's top flat. But it has a 5" tall long range vernier on the rear, so it all works fine. I've always assumed back when that the adapter riser was used to convert the Rem. front dovetail's 7/16" to a standard 3/8 dovetail, and not just to raise the globe.

[Alan in Vermont]

I've got a short/low 17 on my 94. I'm 99% sure it's the .404" one and it works great with a Williams Foolproof on the rear.

[Griff]

Almost all my Winchester 94s have the front sight at ¾", give or take a few thousandths. And with standard rear sights, it gives a nice range of settings that work well with the .30-30.