sighting in. how high at 100 yards?

[D-Rock425]

This is all interesting stuff but I guess I will sight in at 2" high at 100 for now until I get a chance to shoot 200 and then zero it at 200.

[Alan K]

If you get a ballistics calculator and enter in all your information correctly, it will tell you exactly how high you need to at 100 to be dead nuts at 200.  If you ultimately plan to be dead on at 200 it will save you some ammo in my opinion to do it right from 100 rather than essentially sighting in twice, once at 100 and once at 200. Of course you'll want to check it at 200, but at least you wont be shooting multiple groups.

For example, for my hand load for my .300 WSM I'm just 1.36 inches high to dead on at 200, with a sight height of 1.5 inches.  

The calculators are only as good as the data you put into it however, so if you go this route you'll need your elevation, true bullet speed, your BC, your bullet weight, your temperature, and your sight height.  Your pressure is generally calculated based on your temperature and elevation I believe.

[high country]

You will  find sight height makes a good bit of difference....especially at range. B.c. will only be close too and may need adjustment from published info.

[JackOfAllTrades]

Wow, can sure tell we are ready to do some shooting!
I can't believe the fact that there are 2 ways to attack this, correction or compensation. You guys are all compensating, try telling him how to correct now....lol.

I shot this morning! 

As for instructing how to 'correct', if a guy doesn't know where he should sight in at 100yds, I'm doubting he's got target turrets on his scope. I'm also doubting that a 300yd shot is within his capability. (realistic expectation of a kill shot) It's not time yet to teach how to correct when a given range to target is known. Instruction has already been given to keep him in a kill zone out through MPBR.

-Steve

[sakoshooter]

Sighting in dead on at 100 or 200 yds is fine in the timber but spot one good buck across that draw on the next ridge and you'll be kicking yourself.

Not really, you just need to know your rifles trajectory, and hold a little high to compensate for the longer shots. I'd rather have to hold high at 300 yards than hold low at 200 yards. Generally with the longer shots you will have more time to think about it. If I sight my 270 in 3 inches high at 100, it's over 4 inches high at 200. The 3 inches high at 100 yards rule of thumb became popular before laser rangefinders were available, and it kind of made more sense then. Now, with a rangefinder, on the longer shots you don't have to guess at the distance so it's fairly easy to compensate.

According to the trajectory chart on Berger's website, your 270 with a 130gr bullet, using a G1 BC of .450 @ 3000fps sighted in +3" at 100 is also +3" at 200 and -2.25" at 300yds.

[bobcat]

Sighting in dead on at 100 or 200 yds is fine in the timber but spot one good buck across that draw on the next ridge and you'll be kicking yourself.

Not really, you just need to know your rifles trajectory, and hold a little high to compensate for the longer shots. I'd rather have to hold high at 300 yards than hold low at 200 yards. Generally with the longer shots you will have more time to think about it. If I sight my 270 in 3 inches high at 100, it's over 4 inches high at 200. The 3 inches high at 100 yards rule of thumb became popular before laser rangefinders were available, and it kind of made more sense then. Now, with a rangefinder, on the longer shots you don't have to guess at the distance so it's fairly easy to compensate.

According to the trajectory chart on Berger's website, your 270 with a 130gr bullet, using a G1 BC of .450 @ 3000fps sighted in +3" at 100 is also +3" at 200 and -2.25" at 300yds.

Yeah, that's higher than I want it. So somewhere between 100 and 200 yards it's more than 3 inches above line of sight. I'd rather have it hitting a little lower at 200 than it is at 100. That's just my preference. I used to always go by the 3 inches high at 100 yards rule, but I changed over the years. I can sight it in 2 inches high at 100 and still hold dead on at 300. Out at 350 and beyond it's still going to require the use of a rangefinder, or at least a good estimate of the distance, and holding over the appropriate amount. I'd rather have my bullets hitting fairly close to my point of aim at the closer distances when I don't have a lot of time to think about it.

[Smokepole]

The way I was shooting last year, I may as well sight mine in 36" high at 100.  Maybe I could hit the moon.   

Ballistics is a big subject with lots of debate.  Wait till people start talking bout shooting up and down steep slopes and you'll see the sparks fly.  But I'm staying out of this one.  For what it's worth, everyone I know sight their 7MM in 2" high at 100.

[JimmyHoffa]

I was wondering how long until someone brought up the slant range effect....or sighting at sea level and shooting above 5000 ft....or....

[Bofire]

 :)1. the statement "drops from the second it leaves the muzzle" is based on a 'horizontal' barrel.
2. If you have barrel "whip" your barrel is not 'horizontal'.(harmonics also)
3. (for nitpickers) How do you have something 'horizontal' to a orb? or orbital effect?
 however for the virtually zero measureable impact I think we are all safe. 
I vote for MOC, minute of coyote.
ok key board egg heads fire away!!
Carl

[sakoshooter]

I don't get too crazy with math on steep angled shots but I am aware of the affects of it. Being concious of it makes me aim down tight on the heart on either a steep up or down shot. I skip all the inclination formulas and simply use the 1/2 gravity rule. Since gravity has it's greatest affect on a bullet fired basically horizontal, a shot taken 45 degrees up or down would only be affected by half of the normal gravitational pull. Since a 45 degee angle is damn steep, most of us don't usually encounter it(we like to say we did), it usually doesn't come into play enough to make a huge difference. I would venture to say that there is more human error involved in shots taken hunting than gravitational errors.
Half gravity: If you actually use a range finder and it comes up at say; 200yds and it's a steep 45 degree slope(up or down is the same), aim as if it's 100yds. Plus or minus a couple big buck chest hairs, you'll be right in there.

[Smokepole]

I don't get too crazy with math on steep angled shots but I am aware of the affects of it. Being concious of it makes me aim down tight on the heart on either a steep up or down shot. I skip all the inclination formulas and simply use the 1/2 gravity rule. Since gravity has it's greatest affect on a bullet fired basically horizontal, a shot taken 45 degrees up or down would only be affected by half of the normal gravitational pull. Since a 45 degee angle is damn steep, most of us don't usually encounter it(we like to say we did), it usually doesn't come into play enough to make a huge difference. I would venture to say that there is more human error involved in shots taken hunting than gravitational errors.
Half gravity: If you actually use a range finder and it comes up at say; 200yds and it's a steep 45 degree slope(up or down is the same), aim as if it's 100yds. Plus or minus a couple big buck chest hairs, you'll be right in there.

Sakoshooter,

Your rocket science is right on the money.  Long as the wind isn't blowin'.

[D-Rock425]

I thought this gun stuff was simple I guess I was wrong.   I will just keep shooting my bow at least I understand that stuff.

[JackOfAllTrades]

Absolutely no different than shooting a bow. You have different sight pins for your bow intended for different ranges to targets, right? If you don't, you hold high or low depending on distance to target. If anything, a short range bow shooter exagerates the same trajectory of an arrow when compared to the path of a bullet. Shoot an arrow at a down angle. Shoot a bullet at a down angle. It's all the same relative horizontal distance to target vs velocity of the projectile and total distance of the projectile flight horizontal to the gravitational pull of the earth that determines where you should aim/sight-in to get the impact where you want it.

-Steve

[bucklucky]

Holy Crap, whatever happened to  "Keep it simple stupid" 

Practice makes perfect, sight the damn thing in, 2 inches high is fine,  and practice at yardage. Know your gun , know where it shoots at yardage (100, 200, 300, 400, etc) and keep practicing. Your only as good as you can shoot, as long as the gun is accurate.

[Buckmark]

I thought this gun stuff was simple I guess I was wrong.   I will just keep shooting my bow at least I understand that stuff.

It is, ask one question and get 50 different answers.
Go shoot your gun, use the 2 inch @100 as a baseline and have fun, use different ammo and find what your gun likes, and then shoot, shoot and shoot some more, have fun, get comfortable and confident with your equipment and kill a bear...