Estimating range

[Guest colombianito1021]

How big is his head?

I don’t shoot .223 in rifle but my software tells me that a 55 gr .223 zeroed at 50 yards will hit less than an inch high at 100. (.6 to .7â€)

What kind of software are you using? I am interested in something like this. I recently bought an acog and zeroed at 100 and the red dot ontop i zeroed at 25m...would like to know what kind of ballistics i can have by changing zero...

[DaveTN]

What kind of software are you using? I am interested in something like this. I recently bought an acog and zeroed at 100 and the red dot ontop i zeroed at 25m...would like to know what kind of ballistics i can have by changing zero...

Both Federal and Remington have free software you can download. I had a real good one that was way better than either of these, and was free. But now I can’t find it and don’t remember who’s it was.

But here’s a screen shot if anyone recognizes it…. I thought it was from Remington or Federal but it isn’t the same stuff they are offering now.

[Fadex]

I always thought a .223 was pretty flat, at least to 100 yards. 3-4" difference? Are you sure?

[Guest nosnos]

Unless I'm just really shaky and consistently shaky mostly at a hundred yards and shooting high. I shot a bunch of groups (not awesome groups, but groups). Right on at 50 yards. 3-4" high at 100 yards. Am I TOTALLY crazy. LngRngShtr didn't seem to think so.... ??

I guess an earlier statement made by him sums it up. Shoot the gun, check out the groups, write it down, and then you know. There isn't any it shouldn't be this or the book says that. All I know is that my ar-15 is shooting this way. At least, I SWEAR it was shooting this way at the range last time I was there. It's the first time I've really checked out the gun (new build) so maybe next trip to the range I'll figure out that I was doing something crazy.

Until then, if I need to take a shot at 100 yards to save my life, I'm aiming 3 inches low.

[Guest nosnos]

I just found a VERY similar thread over at m4carbine.net...

a new guy need help with zeroing his new rifle - M4Carbine.net Forums

These guys are saying with a 50yd zero expect your POI to be 2" above POA at 100 yds. I found the thread over there pretty interesting....

Edited January 4, 2010 by nosnos

[Guest Ranger Rick]

lets say barrel is 1.5 inches below line of sight so to get to 50 yds. zero we angle the barrel up relative to line of sight,.. the bullet passes line of sight first @ 50 yds. rises up to around 3" at mid range of 100 yds. for our discussion then due to the constant of gravity and a smidge of losing velocity "falls" relative to our line of sight to intersect our line of sight again at 200 yds. then continues to arc down until it finds a backstop.

now if we zero @ 100 yards. the bullet will still be travelling up relative to our line of sight and hit low @ 50 yds. and high @ 200 yds. with a secondary intersection downrange as it drops relative to our line of sight..

simply put.. zero @ 100 yds. put the dot on anything out to 130yds. or so and send it..all things being equal the dot will cover your bullet path from 25 yds. to 130yds. closer than 25 yds. and sight offset dictates you will hit up to 1 1/2" low .

John, thanks for this. Went a long way in helping me "visualize" what is going on in a different way. You a definitely a teacher. Thanks.

Maybe I should rethink my salutation below. Probably should be "Shoot curved... grin more."

[LngRngShtr]

Ranger Rick,

You should always strive to "shoot straight" just realize you may have to send it there in a curving arc or 2 (remember windage also)

Thanks for the compliment, I just find it less frustrating if I understand the "why" behind the "do" versus blind repetition.

I still have the "now how the hell did he....." moments it means my eyes are still open and more to learn and above all I think that was the most important lesson learned..

Learn from everyone you shoot with or against...unless he is shooting at you

John

[Alleycat72]

Name: 223

Ballistic Coeff: 0.272

Bullet Weight: 55

Velocity: 3100

Target Distance: 100

Scope Height: 2.000

Temperature: 60

Altitude: 600

Ballistic Data

~~~~~~~~~~~~~~~

Range Elevation Velocity Energy ETA

0 yds -2.00 in 3100 fps 1174 fpe 0.000 sec

25 yds -1.13 in 3011 fps 1107 fpe 0.024 sec

50 yds -0.49 in 2925 fps 1045 fpe 0.050 sec

75 yds -0.11 in 2840 fps 985 fpe 0.076 sec

100 yds 0.00 in 2756 fps 928 fpe 0.103 sec

125 yds -0.18 in 2675 fps 874 fpe 0.130 sec

150 yds -0.66 in 2594 fps 822 fpe 0.159 sec

175 yds -1.45 in 2515 fps 773 fpe 0.188 sec

200 yds -2.59 in 2438 fps 726 fpe 0.218 sec

225 yds -4.09 in 2362 fps 681 fpe 0.249 sec

250 yds -6.00 in 2287 fps 639 fpe 0.282 sec

275 yds -8.33 in 2213 fps 598 fpe 0.315 sec

300 yds -11.10 in 2141 fps 560 fpe 0.350 sec

325 yds -14.33 in 2070 fps 523 fpe 0.385 sec

350 yds -18.03 in 2001 fps 489 fpe 0.422 sec

375 yds -22.27 in 1932 fps 456 fpe 0.460 sec

400 yds -27.10 in 1866 fps 425 fpe 0.499 sec

425 yds -32.63 in 1801 fps 396 fpe 0.540 sec

450 yds -38.88 in 1738 fps 369 fpe 0.583 sec

475 yds -45.87 in 1677 fps 343 fpe 0.627 sec

500 yds -53.62 in 1617 fps 319 fpe 0.673 sec

Name: 223

Ballistic Coeff: 0.272

Bullet Weight: 55

Velocity: 3100

Target Distance: 200

Scope Height: 2.000

Temperature: 60

Altitude: 600

Ballistic Data

~~~~~~~~~~~~~~~

Range Elevation Velocity Energy ETA

0 yds -2.00 in 3100 fps 1174 fpe 0.000 sec

25 yds -0.80 in 3011 fps 1107 fpe 0.024 sec

50 yds 0.16 in 2925 fps 1045 fpe 0.050 sec

75 yds 0.86 in 2840 fps 985 fpe 0.076 sec

100 yds 1.29 in 2756 fps 928 fpe 0.103 sec

125 yds 1.44 in 2675 fps 874 fpe 0.130 sec

150 yds 1.28 in 2594 fps 822 fpe 0.159 sec

175 yds 0.81 in 2515 fps 773 fpe 0.188 sec

200 yds 0.00 in 2438 fps 726 fpe 0.218 sec

225 yds -1.18 in 2362 fps 681 fpe 0.249 sec

250 yds -2.76 in 2287 fps 639 fpe 0.282 sec

275 yds -4.77 in 2213 fps 598 fpe 0.315 sec

300 yds -7.22 in 2141 fps 560 fpe 0.350 sec

325 yds -10.12 in 2070 fps 523 fpe 0.385 sec

350 yds -13.50 in 2001 fps 489 fpe 0.422 sec

375 yds -17.41 in 1932 fps 456 fpe 0.460 sec

400 yds -21.92 in 1866 fps 425 fpe 0.499 sec

425 yds -27.13 in 1801 fps 396 fpe 0.540 sec

450 yds -33.06 in 1738 fps 369 fpe 0.583 sec

475 yds -39.72 in 1677 fps 343 fpe 0.627 sec

500 yds -47.15 in 1617 fps 319 fpe 0.673 sec

Name: 223

Ballistic Coeff: 0.272

Bullet Weight: 55

Velocity: 3100

Target Distance: 300

Scope Height: 2.000

Temperature: 60

Altitude: 600

Ballistic Data

~~~~~~~~~~~~~~~

Range Elevation Velocity Energy ETA

0 yds -2.00 in 3100 fps 1174 fpe 0.000 sec

25 yds -0.20 in 3011 fps 1107 fpe 0.024 sec

50 yds 1.36 in 2925 fps 1045 fpe 0.050 sec

75 yds 2.67 in 2840 fps 985 fpe 0.076 sec

100 yds 3.70 in 2756 fps 928 fpe 0.103 sec

125 yds 4.45 in 2675 fps 874 fpe 0.130 sec

150 yds 4.89 in 2594 fps 822 fpe 0.159 sec

175 yds 5.02 in 2515 fps 773 fpe 0.188 sec

200 yds 4.81 in 2438 fps 726 fpe 0.218 sec

225 yds 4.23 in 2362 fps 681 fpe 0.249 sec

250 yds 3.25 in 2287 fps 639 fpe 0.282 sec

275 yds 1.85 in 2213 fps 598 fpe 0.315 sec

300 yds 0.00 in 2141 fps 560 fpe 0.350 sec

325 yds -2.30 in 2070 fps 523 fpe 0.385 sec

350 yds -5.08 in 2001 fps 489 fpe 0.422 sec

375 yds -8.39 in 1932 fps 456 fpe 0.460 sec

400 yds -12.30 in 1866 fps 425 fpe 0.499 sec

425 yds -16.91 in 1801 fps 396 fpe 0.540 sec

450 yds -22.23 in 1738 fps 369 fpe 0.583 sec

475 yds -28.30 in 1677 fps 343 fpe 0.627 sec

500 yds -35.12 in 1617 fps 319 fpe 0.673 sec