this is the reticle inside a Herters 3x9 scope, came off of a Herters BSA. I never saw a reticle layout like this:

This reticle follows the idea that you can imprint ballistics data on a reticle.

Fundamentally that is a bad idea because actual trajectories vary widely as a result of differences in ballistics performance and ambient conditions.

Unless you are shooting at very large game, this idea is totally bogus in my "humble" opinion.

Herter's BSA should be ashamed of themselves!

quote:

Originally posted by richj:
this is the reticle inside a Herters 3x9 scope, came off of a Herters BSA. I never saw a reticle layout like this:

Cabelas was offering a setup like that. The circles each represent the same size at their respective distance. Thus you had ranging and hold over built into one device. May be useful if you are climbing steep mountains and need to keep your equipment to a minimum. Lazzaroni Rifles{Savage models} were offered with this scope for a while. My objection was the listed 2.9" eye relief. After all I think this type set up is with a hard kicking rifle not something in the 308win range.

Looks like the circles r probably used to range a deer size tgt. (probably back-brisket) at the ranges specified, but i'd check the 200 yd. subtension and see if it brackest a 16 or 18" tgt. at that range (or u could check it at 100 and see if it's 1/2 those measurements). If it's 2nd focal plane reticle (which it probably is) it'll only be calibrated to work at 1 magnification-- usually the highest. The horizontal lines r supposed to be where your zeros r for the rangefinding ranges indicated, but of course this is a very coarse system, and probably none too accurate. U could measure these subtensions also, and apply the reticle more accurately by correlating the subtensions with a ballistics program, and then shooting to verify.

There r better systems of ranging with that reticle than the way it was designed, by simply applying a modification of the mil-ranging formula described right here under Reticle Rangefinding--

www.ottllc.com/specialtypistols/sp20.pdf

Looks like the tops and bottoms of the circles intersect the vertical axis at 1/2 the distance between the horizontal stadia. This provides aworld of flexibilty to rangefinding, and no less than 7 stadia points for long-range zeroing. Once u learn to apply a tested "tactical" system with this reticle it could serve u well.

The issue with any stadia wire system is the inherent error of being off by as little as one inch. Do the math, and you will see a one inch error on a 15 inch target creates 7% error - at 500 yards, that is a 30 yard mistake, which is enough to miss (remember, half your bullets are going to hit below the point of aim if you are perfectly zeroed).

I would use stadia wires only as a backup to a laser rangefinder.

i think the way to go is to dial up your elevation with target turrents, with the aid of a range finder/cheatsheet....there is no error here
daniel

quote:

Originally posted by AnotherAZWriter:
The issue with any stadia wire system is the inherent error of being off by as little as one inch. Do the math, and you will see a one inch error on a 15 inch target creates 7% error - at 500 yards, that is a 30 yard mistake, which is enough to miss (remember, half your bullets are going to hit below the point of aim if you are perfectly zeroed).

I would use stadia wires only as a backup to a laser rangefinder.

I agree.