bullet drop

DennisP

DennisP

New member
I shoot a savage model 12 in a .223 cal. and have it sited in at 4" high at 100yds. and about 5.5" low at 300yds. How can I figure how much drop there is at 400, 500, 600 yds. ? Not that I want to shoot yotes out that far, but the conversation came up yesterday while hunting and I couldn't answer, so I went out today and shot the rifle at 100 and 300 yds. Is there a simple formula for a person to use to get the general basics. I know there is a lot involved with it, but it would give me a rough idea. Thanks
 
Approximately:
30" at 400 yards
70" at 500 yards
120" at 600 yards

No simple formula unless it's printed on the side of the ammo box.

A lot of things need to be taken into account such as Ballistic Co-efficient, bullet weight as well as muzzle velocity.

Most reloading manuals will have ballistics tables but your gun also needs to be sited in at a certian distance which you did not give us. I guessed at 200 yards and a muzzle velocity of 3200ft/sec using a 55grain FMJ.

Like it was stated before, the tables are just starting points...each individual gun will be slightly different.
 
I've got a trajectory program in my cronograph that tells me.Then I go out and shoot and check against it. Close enough to get me there. Have done it to 400yds but going farther with it soon.
 
look at the ammo company website and look up the ammo you are shooting most of them will have a balistic table
 
I'm still not getting it. Nothing matches up with the website that GrouseSetter gave me http://www.biggameinfo.com/BalCalc.aspx Thanks it was fun to play with though. I plugged all the numbers in I could come up with but it doesn't match what I have. The only thing I haven't done is Chronigraphed it beacuse i don't know anyone who has one. The info I used is: .223 Cal., I'm about 4" high at 100 yds, 5.5" low at 300 yds. I'm guessing zero wil be somewhere around 200 yds, B.C. is .253 amd sectional density is .149, elevation 3700, temp 10 degrees, fps 3250 (According to the local reloading co.), bullet weight is 52 gr hp. It says I should be 1.3" high at 100 yds and 6.7" low at 300 yds. Something has got to be going on there? Can someone help me out?
 
It is hard to say exactly what the deal is, I would guess that you aren't getting quite the velocity that is stated thus a larger deviation in drop. As for an explaination of impact at 100 and 300, it sounds like you may be sighted in closer to the 225-250 range. Again it is very tough to say.
 
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"It says I should be 1.3" high at 100 yds and 6.7" low at 300 yds. Something has got to be going on there? "

That sounds reasonable. 4" high at 100 would give you a zero way out there.

Jack
 
Remington now has a ballistic software on line that you can test for 30 days.Might be worth checking out next to your field testing.It looked like you could get out to 750yds on a few different graphs.You can set your own data or use factory data.I just dabbled a bit and was very impressed.
 
First off--The programs don't always exactly match reality and it's really rough without data from a chrony. But your data doesn't fit.

Remember, your target size is only about 4" to 6" on a coyote. You'd like to be sighted in to shoot the flatter part of the bullets path before gravity really takes hold. (Hold on you other guys, I know that's not really the way to say what happens, but for now and with someone first looking at ballistics I think it will convey the right thought.)

I tried your data in the computer program I use. To get 4" high at 100 yds (which is extremely high for a 223 at 100 yds), you'd still be 5" high at 200 yds, about 3/4" high at 300yds, 11" low at 400, and 33" low at 500.

For a 223 with that velocity and other specs, I'd recommend a 225 yd zero. This would put you at 100yds @ 1.9" high, 200yds @ 1" high and at 300 yds you'd be 5.5" Low. All pretty much within the kill zone of a coyote

Hornady's website now has a nice ballistics calculator.
http://www.hornady.com/ballistics/
or try
http://ballistics.ntinnovations.com/Default.aspx

Good Luck
 
How do you measure your distance to target?
I use my gps or pace it off.
I would suggest a more accurate way if your range will allow.
Me i shoot across my swamp at the hill on the other side
265 by my gps.
 


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