Accuracy At Different Ranges

[Bart B]

Thought I'd sample reader's thoughts on this one. Who knows what may show up for answers?

Let's say a given rifle and ammo shoots 1 inch (one minute of angle, or moa) at 100 yards.

What size in moa will the group be every 100 yards down range to 1000 yards?

[davewilson]

if it's set up to shoot long range i'd say probably .5MOA at 200, and plus about 5-10% every 100 yards after.

Bart

Seems to me when we tested our Palma rifles.....we'd shoot from 800 yds. and if ten rounds would go into 1/2 the X ring...that was acceptable! Those rifles may....or may not have shot exceedingly well from 100 yds. off a bench but there's nothing firm that says that they would have because of the intricate variables involving bullet stability! One would think that if a certain ROT was utilized that all would be well but each rifle is an entity onto itself and what works with one....may not work with another! This goes for reloaded ammo also! Johnie Franklin had a rifle one year that wouldn't shoot worth a "fonk" UNLESS....the ogive was backed off 0.050" off the lands whereby yours/mine....wouldn't have kept them on the shxthouse wall!! But to answer your question more plainly.....if I've got a rifle that I think will shoot 1/2 MOA at 100 yds. I'd expect it to at least hold 2/3 of the ten ring at 1000 and I'll let God and the law of averages deal with the X count!! And the only way to tell what one is capable of is to put a rifle into a very well made "fixture"....pick a day that is good.....and see what comes up on the target face downrange! When I was with the Army Team....we had M-14s that would shoot ten shot groups into 4" from 600 yds. and that my friend is good ammo; Lake City Match it was!! [img]/ubbthreads/images/graemlins/grin.gif[/img] [img]/ubbthreads/images/graemlins/grin.gif[/img]

[sambo3006]

Just for the sake of correct terminology, one MOA roughly corresponds to one inch at 100 yds (I think it is ever so slightly larger than one inch). So one MOA would be roughly 2 inches at 200 yds and so on. I have not shot at ranges farther than 400 yds, but even at that moderate distance, a 0.5 MOA gun at 100 yds does not necessarily stay in 0.5 MOA @ 400 yds. Lots of factors. I hope to find a spot to shoot farther, as I have been wondering basically the same thing as you for a particular rifle.

[Bart B]

Sambo3006, a trig minute of angle at 100 yards is 1.0472 inches. But a shooting minute of angle at 100 yards is exactly 1 inch. That was decided many years ago when sight radius on most target rifles was 30 inches and a 40 thread per inch lead screws in the rear sight was standardized. One turn on the windage or elevation knob moved the sight .025-inch; one-third turn moved it .008333 inch. 30 inches divided by 3600 (number of inches in 100 yards) equals .0083333-inch.

Most USA NRA smallbore and highpower rifle targets have scoring ring diameters based on this axiom as does most US made aperture rear sights' adjustments.

[sambo3006]

[ QUOTE ]
if it's set up to shoot long range i'd say probably .5MOA at 200, and plus about 5-10% every 100 yards after.

[/ QUOTE ]
Bart, this is what I was mainly getting at as far as clarifying the concept of the MOA. Obviously if the gun shoots 1 MOA @100yds, it shouldn't do 0.5 MOA @ 200(No offense to Dave Wilson). I didn't know the origin of how the shooting MOA came about, that is interesting. I guess I could have looked up the exact value of the minute of angle, but I'm too lazy! Thanks for the illumination! Sam

[davewilson]

Sam, you obviously haven't shot much at long range to not understand that a gun can shoot better moa at 200 than it can at 100.i once saw a 1000 yd bench gun almost thrown away on it's first outing because it shot around 2" at 100 yards.a young fellow who just started working there asked if he could shoot it and they said go ahead, it's a piece of sh. as the rest laughed at him he took a target out to 300 yards.the guy that built the gun wanted to shoot it again when the kid put 5 in less than an inch.they repeated this a couple of times and confirmed that it was dogpoop at 100 yards.but somewhere between 1 and 300 yards they went to sleep very well.