HELP! Brain Melting...

djcompto · #1 02-15-2005, 06:45 PM

Okay everyone, I need some serious explanation! I am baking my poor brain trying to figure the math on my target turrets. I have never used a scope with turrets before and I am just lost. I have looked at ballistics tables, and if I am reading things correctly, I can expect over 230 inches of drop from my 7mm RemMag at 1000 yards. Is this right!?? If so, my turrets are 1/8 MOA incremental. I don't have enough darn clicks to dial for 230 inches of drop! Am I just totally confused? Someone help before I go nuts! Thanks! Dan

308 nate · #2 02-15-2005, 07:03 PM

Hi Dan,
Yes this would be a problem.
But what you are forgetting is that 1MOA = aprox 1" at 100 yds. but 1 MOA at 1000 yds = aprox. 10" so from 100 yd zero,if you have 230" of drop you would need to adjust 23 MOA on your scope which is 184- 1/8 minute clicks, your turrits should also have a 1 MOA scribe on them to speed things up.You should not have to count 184 clicks. Most of your scopes out there are going to have at least 23 minutes of up adjustments from center but if you are running out of adjustments you will need a canted base or Burris rings with offset inserts.
I hope this makes sence if not let me know and I will try to explain differently.
308nate

4ked Horn · #3 02-15-2005, 07:12 PM

Calm down. Everything's going to be OK. [img]/ubbthreads/images/graemlins/wink.gif[/img] (nate you just beat me with your response. [img]/ubbthreads/images/graemlins/shocked.gif[/img])

Remember that Minutes of angle (MOA) are an angular measurement. It grows with distance. 230 inches of drop at 1000 yards is (somewhat) only 23 inches of drop at 100 yards and I know your scope can handle this. It equates to around 23 MOA which for your scope is 184 individual clicks.

I am going to be right back with a link for a website for you to look at and play with. The "come ups" are what you set your turrets for to compensate for the drop of your bullet. When you see what the MOA come ups are for your bullet you will see that the inches of drop are a much bigger number than the MOA you must adjust to put the bullet back on the crosshairs.

Here is your link. Under "Load definition" be sure to set your "Clicks/MOA" to 8. Your calculated drop chart has the ability to give you your Come-ups in MOA + Clicks whis means you dial in full MOA first and then individual clicks (1 thru 7) It's very cool.

Please feel free to ask any questions you still have.

djcompto · #4 02-16-2005, 11:17 AM

Okay, so here is what I came up...my problem was actually downright stupid! I didn't realize that as I turned the turret knob past the 7 moa hash (the last hash on my scope) that another scale of horizontal bars began to show on the barrel of the turret. I thought I only could go to 7! Duh! I just need to read the horizontal scale to keep track of how many times past zero I have traveled. There are 4 clicks between 7 and Zero, so that means that one full rotation from Zero back to Zero is 60 clicks or 7.5 moa. So let's say for that 1000 yard shot, I need to go past zero 3 times plus 4 clicks. I think I get it now. By the way, that website link you gave is great!!! Thanks for the help guys

Mysticplayer · #5 02-16-2005, 12:43 PM

OH NO, you have one of 'those' turrents. I feel your pain as I have one like that too. Drives me insane because quick math under pressure is not my idea of fun.

when I make up my drop table, I will spell it out by rotations and clicks. I don't want to do two rotations is 15 plus ...

all my other scopes have full min per rotation whether it is 8, 12 or 14. Whoever came up with 7.5 should be shot.

There my rant for the day. Thanks for listening.

Jerry

4ked Horn · #6 02-16-2005, 03:32 PM

Your turrets will probably have clicks left over even after your erector tube stops moving (hits the top of the scope tube).

Do this at the range:
1. Rest your gun solidly on sandbags or a bipod and look through your scope.
2. Now turn the elevation turret and watch the picture move (It will move opposite of the way you are turning the knob. Its supposed to.)
3. As you come to the end of the turret movement the picture will stop moving. Note this turret position (20 something MOA and X number of clicks) THIS IS THE EXTENT OF YOU AVAILABLE MOA ADJUSTMENT. Any other turret adjustment in this direction will have NO EFFECT ON YOUR TRAJECTORY. If you need more adjustment to shoot farther you will need a tapered base or rings to lose down movement and add it to your up movement. I did this on my humble little .308 and I can shoot the crosshairs out to around 1200 yards.