sighting in at 25ydrs

[caddisman]

Okay, as I understand it. If you sight in your rifle at 25 yds it is the same at a 100 yds, trajectory wise.

If I have sighted in my riffle to be 3" high at 100 yds so that it is zero at 300 yds, does that change the 25 yd sight in?


Thoughts!

[1899b]

[bat119]

What cartridge-bullet weight are you shooting ?

The speed and bullet weight/shape (ballistic coefficient) determines your trajectory.

Different cartridges will have different trajectories

[IAMhunt]

Originally Posted by caddisman

Okay, as I understand it. If you sight in your rifle at 25 yds it is the same at a 100 yds, trajectory wise.

If I have sighted in my riffle to be 3" high at 100 yds so that it is zero at 300 yds, does that change the 25 yd sight in?


Thoughts!

Maybe, Maybe not.

[58thecat]

Sight in at 25 yards then that's your range to the intended target to be shot....man I sight in at 100 bang on for this area....I stretch it out to 200 just to ensure point of impact...never assume because the reloading manual or box of ammo says so.....just saying eh

[mindoutside]

My 3006 150 gr I was shooting zeros at 250. Bulls eye at 25 yards, 3.5 moa high at 100

Gotta check your own bullet and rifle

[Jack fish hunter]

25 yards is zero at 250 will shoot high at 100

[Tronneroi]

I zero three of my rifles at 25. They shoot an 1.5" or so high at 100.

[Chuck_Wagon]

Originally Posted by caddisman

Thoughts!

Google search for a ballistic calculator online, key in your rifle and cartridge information to look at the specifications for your particular bullets flight path.

[elkhunter11]

Actually, sighting in 1" high at 25 yards, will often result in the point of impact being high at 100 yards. As to sighting in at 25 yards, the only way to know for sure where the point of impact will be at 100,200, and 300 yards, is to shoot at 100,200 and 300 yards.

[Flight01]

My 308 shooting 165 nosler partition is easy to remember and proven for me.

On at 25yards is 2.5” high at 100 and on again at 225yards.

But you have to prove every load and rifle combination before you take it to the field on game.

[warriorboy10]

Whatever calculations you decide to use it is imperative that you prove those calculations by shooting at distance. Very high possibility of wounding an animal never mind totally unethical!! No guessing, you must be sure!!

[Lefty-Canuck]

Actually shoot your firearm and sight in to a tested zero, then practice to the maximum range you plan on shooting. Proof is in the pudding.

LC

[Sashi]

I only use the 25 yd sight in , so that I'm on paper at 100.

[270person]

It's called MPBR or maximum point blank range and I've used it. I zero my 7mm at 27 yds using 160gr NP's with the theory being the bullet will rise to a max height over distance before it starts to fall off. If I remember how to explain it correctly mpbr is the equal measurement between the high and low point.

E.g. I sight at 27 yds, the bullet rises 2" and max apogee at 162 yds, begins to fall off and is 2" low at 261 yds. I know that between 27 yds and 253 yds I will be able to hit a 3" area.

Numbers above are just pulled out of my arse but it's the old, " I can hit a pie plate, or a deers vitals area, at any range between 27 and 253 yards by aiming at centre." I will never be more than 2" low or 2" high which is just fine.

I would encourage you to still take a whack or 3 at various yardages just to see what's what but the mpbr method can save ammo and time getting zeroed. If you can't hit paper at 25-27 It's quite likely you won't be able to hit an SUV at 300.

[spoiledsaskhunter]

Originally Posted by Sashi

I only use the 25 yd sight in , so that I'm on paper at 100.

exactly.....then do your homework by shooting further. you can't just shoot @25 and think you're going to be able to predict what going to happen at other yardages.

[ronkaren]

Originally Posted by Sashi

I only use the 25 yd sight in , so that I'm on paper at 100.

yup. and usually high at a 100, depending what i'm sighting in.

[KegRiver]

Originally Posted by caddisman

Okay, as I understand it. If you sight in your rifle at 25 yds it is the same at a 100 yds, trajectory wise.

If I have sighted in my riffle to be 3" high at 100 yds so that it is zero at 300 yds, does that change the 25 yd sight in?


Thoughts!

It sure does.

plus zero at 25 equals zero at 100 is a flawed theory.

It might work with one bullet weight in a particular cartridge and not a heavier of lighter bullet in the same cartridge or even with a different velocity with the same bullet cartridge combination.

It is only useful for rough sight in and then only if you can't hit the target at 100 yards due to scope or sight alignment being to far off.

I've been told that most modern rifles zeroed at 25 yards will be 2 inches high or more at 100 yards.
My charts don't list anything with a 25 yard zero. 50 is as low as they go. But they suggest to me that three inches high at 100 with a 25 yard zero is more likely what one would find with most modern cartridges.

[270person]

Originally Posted by KegRiver

It sure does.

plus zero at 25 equals zero at 100 is a flawed theory.

It might work with one bullet weight in a particular cartridge and not a heavier of lighter bullet in the same cartridge or even with a different velocity with the same bullet cartridge combination.

It is only useful for rough sight in and then only if you can't hit the target at 100 yards due to scope or sight alignment being to far off.

I've been told that most modern rifles zeroed at 25 yards will be 2 inches high or more at 100 yards.
My charts don't list anything with a 25 yard zero. 50 is as low as they go. But they suggest to me that three inches high at 100 with a 25 yard zero is more likely what one would find with most modern cartridges.

This calc is pretty decent. Pop in your BC, muzzle velocity, atmospheric conditions if you so choose and hit calculate. Sight in for zero at the Near Zero yardage. Chart tells you the rest by yardage. It's actually pretty damned accurate surprisingly.

www.shooterscalculator.com/point-blank-range.php

[Dick284]

A 25 yd sight in, gets you on paper at 100 yds, but so does a good old fashioned sand bagged bolt removed bore sighting job(unless it’s a pump, lever or a semi)

You still need to shoot at distances beyond 25 yds to determine if one load shoots better than another, and to further confirm what your rifle does at expected hunting distances.

Charts and calculators are sure nice until you realize that theory and reality seldom align 100%

Be a responsible hunter and shoot to the maximum range you intend to hunt, you owe it to the game we hunt.

[58thecat]

Charts are like farts...ya just never really know

[KegRiver]

Originally Posted by 270person

This calc is pretty decent. Pop in your BC, muzzle velocity, atmospheric conditions if you so choose and hit calculate. Sight in for zero at the Near Zero yardage. Chart tells you the rest by yardage. It's actually pretty damned accurate surprisingly.

www.shooterscalculator.com/point-blank-range.php

I'll have to check that out. I'm still doing it old school.

IE; reading charts in a book. LOL

Thanks.

[KegRiver]

Something else to consider.

the width of one bullet off dead center would translate to somewhere around two inches off dead center at 100 yards.
That's not exact mind you. I didn't crunch the numbers to get an exact figure.

The point is, sighting in at 25 yards can fool a person into thinking you'll be dead on at 100, when in fact you could be off by a lot more then you would imagine.

Distance amplifies deviation plain and simple.
Talking only left and right, one inch off at 100 = 2 inches off at 200 and 3 inches off at 300.

2" off at 100 = 4 inches off at 200 and on it goes.

The same principle applies to the vertical as well but one has to add normal bullet drop to the calculation.

[tullfan]

30-06, on paper at 25 yards, then on paper at 100 yards, zeroed. Then verified at 200 yards, low. Adjusted. 200 yard zero, dropped nice 8 point at 234 yards.
Need to confirm where your bullet is going. Pie plate is ok if you’re baking but you are taking an animals life. You really want an ethical shot. At least I do.
Tullfan

[caddisman]

Originally Posted by bat119

What cartridge-bullet weight are you shooting ?

The speed and bullet weight/shape (ballistic coefficient) determines your trajectory.

Different cartridges will have different trajectories

7mm Win Mag 160g win XP3 ballistic silver tip. Maybe I failed to mention that I did sight my rifle in before at 100 yds 3" high and then shot it at 300 yds to a bullseye. When I was lending my rifle to a first time hunter to use, he dropped it in it's hard case on a carpeted floor. So when we went out I just wanted to make sure that it was still shooting straight. I have bumped the rifle before and never had an issue. It has been shooting great for me for years without any adjustments.
I hear what everyone is saying about testing it out at long range to be sure. Lots of great advice and I will check out those ballistic calculators to see if I am on track.

[Flatlandliver]

Originally Posted by tullfan

30-06, on paper at 25 yards, then on paper at 100 yards, zeroed. Then verified at 200 yards, low. Adjusted. 200 yard zero, dropped nice 8 point at 234 yards.
Need to confirm where your bullet is going. Pie plate is ok if you’re baking but you are taking an animals life. You really want an ethical shot. At least I do.
Tullfan

You must shoot at distance to confirm for sure.

[sheep]

Originally Posted by Sashi

I only use the 25 yd sight in , so that I'm on paper at 100.

this is the only thing a 27yard shot is good for. My father inlaw a few years ago said "I don't know why I missed that buck, my gun is perfect at 27yards" I tried to explain that 2" high at 27yards was a bad practice, and did not mean 2" high at 100yards. We shot at paper at 100yards and it was 11" high. Deer was at 240, which is was about 20" high, and he aimed high on the deer.

Bottom line,0 at 27yards is close to a zero at 100yards but still need to shoot at 100yards.

[Purple Farmer]

Originally Posted by Dick284

Charts and calculators are sure nice until you realize that theory and reality seldom align 100%

Be a responsible hunter and shoot to the maximum range you intend to hunt, you owe it to the game we hunt.

This x 100.

There are too many guys running around taking shots that they have no chance of connecting accurately. and too many guys that put no time in at all into understanding how to hunt.

[huntsfurfish]

Surprised this thread is still in General discussion.


edit:
Then again everybody probably out hunting.

[elkhunter11]

I watched one individual sight in his new Huskemaw scope at 25 yards, and then declare to his friend, that he was good to 800 yards. His friend asked if he was going to verify the point of impact at longer ranges, and his reply was " why waste the time and ammunition, the turret is calculated to 800 yards."