The Firing Line Forums - View Single Post - At what distance do you set your CQB sight at?

Metal god · August 12, 2013, 12:09 PM

I was just running some numbers through my ballistic calc for the AR with a 55gr bullet at 3000fps. IMHO If you want the best zero for home defense , the 100yd zero is best . Like what was said above . There is NO way to make up for your barrel being below the optic or sights with said sight . No matter where your zero is the bullet will leave the barrel 1.75" to 2" below the sights . Knowing this to be true a 100yd zero will be 1.75" low at the muzzle . dead on at 100yds and 1.75" low again at 175yds . That gives you an extreme spread of 1.75" all the way to 175yds . In contrast the 25yd zero would put you 3.5" high at 100yds with an extreme spread of 6" out to 300yds . A 25 foot zero would put you some where around 12" to 16" high at 100yds and the extreme spread would not even be worth talking about .

So it looks to me that for HD/SD the 100yd zero is best for your AR .

August 12, 2013, 12:09 PM	#33
Metal god Senior Member Join Date: April 10, 2012 Location: San Diego CA Posts: 6,875	I was just running some numbers through my ballistic calc for the AR with a 55gr bullet at 3000fps. IMHO If you want the best zero for home defense , the 100yd zero is best . Like what was said above . There is NO way to make up for your barrel being below the optic or sights with said sight . No matter where your zero is the bullet will leave the barrel 1.75" to 2" below the sights . Knowing this to be true a 100yd zero will be 1.75" low at the muzzle . dead on at 100yds and 1.75" low again at 175yds . That gives you an extreme spread of 1.75" all the way to 175yds . In contrast the 25yd zero would put you 3.5" high at 100yds with an extreme spread of 6" out to 300yds . A 25 foot zero would put you some where around 12" to 16" high at 100yds and the extreme spread would not even be worth talking about . So it looks to me that for HD/SD the 100yd zero is best for your AR . __________________ If Jesus had a gun , he'd probably still be alive ! I almost always write my posts regardless of content in a jovial manor and intent . If that's not how you took it , please try again .