Well, I just got my first set of target knobs, but haven't used them yet. However, before I start, I have a really stupid question to ask you guys.
Let's say my gun is zeroed at 100 and I'm shooting a hog at 300. According to my ballistics chart, the bullet will drop 8" at 300. Do I raise my scope 32 clicks (1 click = 1/4" at 100), or do I raise it 11 clicks because at 300 yds 1 click will equal 3/4"? I think I know the answer, but guys have told me both answers and I just want to make sure from those of you who TRUELY use them.

In actuality, the click does not move the impact 1/4 inch at 100 yards, but 1/4 minute of angle at 100 yards. That works out to real close to 1/4 inch, but does lead to this confusion. Use the 1/4 MOA and you see exactly what is happening. One MOA at 100 yards is roughly 1", 200 yards, 2", and 300 yards, 3 inches. So, if one click moves the impact 1/4 MOA, then you are moving the impact 1/4 MOA at all ranges, so at 300 yards, 1/4 of 3" is 3/4 inch. Each click now moves the impact 3/4 inch at 300 yards. Since 8" at 300 yards is 2.66 MOA (8 divided by 3), you need to put in 2.66 MOA of adjustment, with 1 click equal to 1/4 MOA, you need between 10 (2.5 MOA) and 11 clicks (2.75 MOA), just like you said.
While all this may make it sound confusing, if you get rid of the idea of inch movement and use MOA, it works out at all ranges and for me anyway, becomes much less confusing.

jethrow, If you know the muzzle velocity of your load and also the BC of the bullet you're shooting and will email me. I'll generate you a click chart for that load. Saves a lot of time and components!!!! GHD

This is a click chart I made for my big gun...It is in M.o.a..... If I have a range to my target is 900 yards.I look at the chart.It says 17.7 M.O.A.....That comes out to 70.8 clicks which I round up to 71 .25 INCH CLICKS..

[ 05-12-2003, 05:55: Message edited by: Boyd Heaton ]

Jethro
This is not a stupid question.
Bigbore is correct. If you can creat a drop chart in M.O.A. you are way better off.

If not try this simple formulae.

Range X .01047 (moa conversion). Divide drop by answere.
Multiply by 4 to get clicks.

Or. 300 x .01047=3.141
8 inches drop divided by 3.141 =2.547
2.547 x 4= 10.188 clicks

10 clicks not 11 clicks!!
Surprised??
This is another reason that most guys shouldn,t be shooting big game at long range.
That .00047 difference is enough to miss a deer at 600 yards.
This only works if your scope is true moa calibrated but should be close enough for gophers.

Have fun!
Jamie

Thanks guys, that clears everything up.

GD, do you use a program for the chart or do you just calculate it by hand?

Last night I took X-man's formula and punched it into Microsoft Excel to make a handy chart. It worked great! Best of all, I can use this for other calibers. Just change my drop numbers and it will automatically calculate the clicks. The other good thing is that with Excel you can print as small as you want. Nice feature to use when you want to shrink it, laminate it, and tape it to your stock.

Thanks guys!

jethrow, I use a program!! You want me to do math? Seriously, My dad said on the way to my graduation ceremony, "Son, I don't know why you're getting a degree in Dairy Science! You haven't done anything but work on rifles and shoot groundhogs for 4 years!!! GHD

GHD:
Darn I missed those classes when I was in college!
Must have been asleep at registration (every term)!
I would have really enjoyed higher education if I had known that you could work on your rifles and shoot groundhogs for credit.
Maybe I could re enroll.
You must have gone to the very best school!

muck

[ 05-14-2003, 08:24: Message edited by: muck ]

Hey jethro, I'd strongly encourage you to "verify" your Drop Chart values by actually shooting some groups on paper at the distances you intend to shoot.

Occasionally the calculations from mathmatical models come fairly close - other times they don't. The only real way to create a valid Drop Chart is through actual shooting the exact bullet and load you intend to use at a specific distance and record the change needed to compensate for the drop.

By the way, don't be surprised if you need to add some "Windage" which is not caused by the wind.

Good luck to you.

Hot Core.
That's the best advice I've heard in a long time!
Some bullets don't work very well with existing computer models.
Certain Hornady SSTs, Nosler Bts, and Swift Sciroccos can be right off the computer map at ranges beyond 300 yards.

Jamie

Righto!!

x-man....just how much does being one click off at 700 change your point of impact?????

jethro, I always try the loads out against the charts I generate and for the 222Mag, 243, 25-06,6x284 and 260 and 7mmMag, what I have tried has been remarkably close on my 400 yard range. The 6x284 was tried at 500 and was dead on but that is the only one that I've seen it tried on over 400. Around here it's hard to get a place to shoot those 7-800 or 1000 yard ones!
MUCK, I graduated from VA TECH, class of '78! I never got any credits from my gun exploits but I didn't let shool interfere with my education!! GHD

Boyd,
In theory bullet impact would change about 1.8 inches at 700 yards.
I'm not sure but I guess you are calling me on " 1 click missing the deer at 600 yards". In itself that would be an exageration of course, but you were the only one that called me on it.
I spent several years trying to become a good long range hunter only to fail at my quest. I guess my point is that unless you have actually tried it there is no descibing just how difficult and variable your chances are for making a good hit.

Jamie

And don't forget the freaking WIND. You can know exactly what your bullet does every inch of the way out to 1000 yards, and it all goes to hell in a hand basket because a gust of wind catches the bullet 200 yards from the muzzle and blows your group all over the country side. I've never been able to dope wind well, and what it will do to a .50 BMG bullet at 500 yards is truly humbling, much less what it will do to lighter bullets at equal or longer range. Wind is maddening enough with paper punching, but doing it with live game where the stakes are much, much higher, I won't even think about it past 300 yards if there is even so much as a whisper of wind.