Sighting "in" at 25yds, Where is it at 100yds?
#1

I'm limited at "my place" to a shooting range of 50 yds. I've heard that a rifle sighted in at 25 yds. will be within an inch or so at 100 yds. Any thoughts?

#2

etw, if you want a rough gauge goto Remingtons website and download a program called Remington Shoot! It is free and will give you some starting points for sight in, you can pick only from Remington offerings but should be able to get close for other manufacturer's with style and grain. Although I would recommend you still go out to an area where you can shoot 100 or whatever your desired zero or hunting distance maybe to find out for sure how your bullet combo will perform.
#3
Guest
Posts: n/a

Depends on velocity, BC, sight height. For example for my 300RUM with 190gr bullet moving at 3200fps, I am -.79" from zero at 25yards but if I have 2.5" see thru scope mounts, I am -1.54" at 25 yards. If I sighted the gun at 25yards with my 1.5" scope rings, I would 6" high at 100yards. Not what you want.
#4
Nontypical Buck
Join Date: Feb 2003
Location: Gypsum KS USA
Posts: 1,289

Ok, I'm really going to sound mean here, but truth be told, I usually am mean....Shooting your gun and sighting in at 25yrds thinking it will be then sighted at 100yrds is just stupid...there are hundreds if not thousands of these idiotic charts running around even in our "modern age of enlightenment", they are a starting off point only, basically so you can take a freshly boresighted rifle to the range, shoot at a target say 14" square at 25yrds (which would be 56MOA, easier to hit than 14MOA), get your shots on the page to the point you'll know they'll be on paper when you push things back to 100yrds.
You also didn't say what cartridge/bullet weight/bbl length/muzzle velocity/balistic coefficient you'll be shooting, I can sight in a .22lr to shoot one ragged hole at 25yrds, that doesn't mean it will be on at all at 100yrds, nor is it necessarily true for a .30-06.
You live in TX, there are rifle ranges all over in TX, my advice is get your rifle "rough sighted" on your 50yrd range then head out to a 100yrd+ range.
The only real way to know where your rifle/load is going to hit at 100yrds is to shoot at 100yrds.
You also didn't say what cartridge/bullet weight/bbl length/muzzle velocity/balistic coefficient you'll be shooting, I can sight in a .22lr to shoot one ragged hole at 25yrds, that doesn't mean it will be on at all at 100yrds, nor is it necessarily true for a .30-06.
You live in TX, there are rifle ranges all over in TX, my advice is get your rifle "rough sighted" on your 50yrd range then head out to a 100yrd+ range.
The only real way to know where your rifle/load is going to hit at 100yrds is to shoot at 100yrds.
#6
Join Date: Jun 2004
Posts: 17

Nomercy is absolutely right. You cannot sight in at 25 yards, and then be able to say with any certainty whatsoever where it will be at 100. I have had rifles be pretty close at 100 after sighting in at 25, and then I have had them off the paper at 100. The only way to know for sure where it will be at 100 is to shoot it at 100. Shooting it at 50 will help somewhat, but really you need to shoot it at 100.
Vinny
Vinny
#7

ORIGINAL: etw I'm limited at "my place" to a shooting range of 50 yds. I've heard that a rifle sighted in at 25 yds. will be within an inch or so at 100 yds. Any thoughts?

#8
Giant Nontypical
Join Date: Feb 2003
Location: fort mcmurray alberta canada
Posts: 5,667

Nomercy is absolutely right. You cannot sight in at 25 yards, and then be able to say with any certainty whatsoever where it will be at 100
I agree completely.Taking a gun hunting that has been sighted in at 25 yards and then shooting at game at 100 yards or more is irresponsible.
#9

A gun that is sighted in at 25 yards is fine for hunting...AT 25 YARDS!
25 yards, or thereabouts, is a great place to start sighting in a load. I do it all the time. I consult the ballistic charts for the appropriate bullet BC and velocity, and measure the height of the sight from the center of the bore to the line of sight, and see for a 100 yard zero where the bullet crosses the LOS the first time. I then set up my target initially at that range. Usually that happens between 20-30 yards, depending on sight height and velocity.
The point of this is that initially setting up at about 25 yards virtually guarantees that the rounds will hit paper, allowing for initial adjustments. Once I've got it zeroed at 25 yards or thereabouts, I can be reasonably certain that I'm going to hit paper at 100 yards, thus saving me time and ammo trying to get on target. By zeroing at 25 first I can USUALLY get within 4-6" of zero at 100 yards every time, but there are NO guarantees. Like the others have said, the only way to be certain of your zero at 100 yards is to actually shoot at 100 yards.
One of the reasons the 25 yards zero might not be an accurate reflector of the POI is 100 yards is because of bullet stability issues. Bullets often tend not to be fully stabilized within 25-75 yards of leaving the muzzle, yawing and occillating enough to create a spiral-like flight path. It takes a small amount of time to dampen the bullets occilation and allow the bullet to settle into a straight stable flight pattern.
I think it ultimately comes down to an ethical issue. If you sight in a 25 and trust to the ballistic charts, you'll never be certain that you're POI is close enough to your POA to ensure a quick ethical kill. To me, and most of the people who frequent this board, hunting with a rifle whos zero is uncertain is a recipe for a wounded animal, and is therefore ethically unacceptable. You owe it to yourself, the animal and the rest of us in the hunting community, and for the sake of our future as hunters and sportsmen, to ensure your chosen weapon is up to the task of ethically taking game. Failing to sight your rifle in at the range you intend to use it, and wounding an animal as a result, makes you a slob hunter and gives all of us a bad name. I'd ask you to not do this.
Mike
25 yards, or thereabouts, is a great place to start sighting in a load. I do it all the time. I consult the ballistic charts for the appropriate bullet BC and velocity, and measure the height of the sight from the center of the bore to the line of sight, and see for a 100 yard zero where the bullet crosses the LOS the first time. I then set up my target initially at that range. Usually that happens between 20-30 yards, depending on sight height and velocity.
The point of this is that initially setting up at about 25 yards virtually guarantees that the rounds will hit paper, allowing for initial adjustments. Once I've got it zeroed at 25 yards or thereabouts, I can be reasonably certain that I'm going to hit paper at 100 yards, thus saving me time and ammo trying to get on target. By zeroing at 25 first I can USUALLY get within 4-6" of zero at 100 yards every time, but there are NO guarantees. Like the others have said, the only way to be certain of your zero at 100 yards is to actually shoot at 100 yards.
One of the reasons the 25 yards zero might not be an accurate reflector of the POI is 100 yards is because of bullet stability issues. Bullets often tend not to be fully stabilized within 25-75 yards of leaving the muzzle, yawing and occillating enough to create a spiral-like flight path. It takes a small amount of time to dampen the bullets occilation and allow the bullet to settle into a straight stable flight pattern.
I think it ultimately comes down to an ethical issue. If you sight in a 25 and trust to the ballistic charts, you'll never be certain that you're POI is close enough to your POA to ensure a quick ethical kill. To me, and most of the people who frequent this board, hunting with a rifle whos zero is uncertain is a recipe for a wounded animal, and is therefore ethically unacceptable. You owe it to yourself, the animal and the rest of us in the hunting community, and for the sake of our future as hunters and sportsmen, to ensure your chosen weapon is up to the task of ethically taking game. Failing to sight your rifle in at the range you intend to use it, and wounding an animal as a result, makes you a slob hunter and gives all of us a bad name. I'd ask you to not do this.
Mike