Long Range Hunting Online Magazine


Go Back   Long Range Hunting Online Magazine > Rifles, Reloading, Optics, Equipment > Reloading

Reloading Techniques For Reloading


Reply

.243win 75g vmax help

 
LinkBack Thread Tools Display Modes
  #8  
Old 07-08-2013, 04:41 PM
Silver Member
 
Join Date: Nov 2011
Posts: 231
Re: .243win 75g vmax help



This is from today. One hit at 510 yards with 7MOA up and one hit at 400 yards with 3.75MOA up.. There was a slight right to left wind.. I put 3500fps into my calculator and it gave me 6.96moa for 510... But called for 4.26moa @ 400.. I saw that impact high.. I can down to 3.75 and hit on the next shot. I'm using the listed 330BC for the 75vmax..

Earlier today I set out 6 half gal juice jugs 2 each at 200,300 and 360.. 200 yards called for .75, 300 was 3.00moa and I dialed 3.5 for 360 yards. Once I made hits on them all I shot the remaining jugs in random order dialing for adjustments, hits were repeated.. How do I make the calculator more accurate.

I'm using ballistic AE.
Reply With Quote
  #9  
Old 07-08-2013, 04:52 PM
Silver Member
 
Join Date: Sep 2009
Location: South Dakota
Posts: 381
Re: .243win 75g vmax help

You're listed BC of .33 is either incorrect (It's an advertised number by Hornady) and is not working with your system. Or your optic is not tracking true.

Bullet drop doesn't lie.

3,4 and 500 yds is not far enough to "true" your velocity and bc.
You're putting in bad info and you're getting out bad info.


Edit...
It would probably be easier if you list ALL of the data you're putting into your app so we can either try and duplicate, or correct the issue...because the drop chart you're getting doesn't jive.

These are the numbers where you're making contact?
200 - .75 MOA
300 - 3 MOA
360 - 3.5 MOA
400 - 3.75 MOA
500 - 7 MOA

Just by looking at the numbers, something is WAY off.
You need 1.25 MOA additional elevation to go from 200 to 300 (not impossible)....but then from 3-400, you only need an additional .75. This IS impossible.


I'll give you the atmospheric data that I have here currently, with the published .33 BC and I'll show you what I'm talking about. This is not necessarily true for you, just an example.

My station pressure is 28.45, temp is 80, powder temp is 80, humidity is 50%, velocity at 3500,
Range card craps out numbers as follows.
100 - 0 MOA
200 - .5 MOA
300 - 1.9 MOA
400 - 3.8 MOA
500 - 6.1 MOA
600 - 8.8 MOA
700 - 12 MOA
800 - 15.7 MOA

SO, if you take your rifle out and shoot at 800 yds, and you need 16 MOA to get on target...then one of two things is necessary. Either you're velocity is off or your BC is off. Take a shot at 400 and note where it impacts on the target.
You'll have two TRUE numbers. 16 MOA at 800 and (for example) 4 MOA at 400.
When you consult the range card, you see these don't match up, so either the velocity or BC is wrong.

To check, you can adjust your velocity and bc until you get a combo that matches BOTH of your real world bullets.
__________________
"We do not rise to the occasion...we fall to the level of our training."

Last edited by c_bass16; 07-08-2013 at 05:23 PM.
Reply With Quote
  #10  
Old 07-08-2013, 05:17 PM
Silver Member
 
Join Date: Nov 2011
Posts: 231
Re: .243win 75g vmax help

Thanks.. I'll look for a spot to get 7-800 like you said
Reply With Quote
  #11  
Old 07-08-2013, 05:21 PM
Platinum Member
 
Join Date: Feb 2011
Location: Cincinnati, Ohio
Posts: 1,786
Re: .243win 75g vmax help

Quote:
Originally Posted by 1tonpower View Post

Yepper...I see it now and deleted my previous post
Reply With Quote
  #12  
Old 07-08-2013, 07:56 PM
Silver Member
 
Join Date: Nov 2011
Posts: 231
Re: .243win 75g vmax help

Brass 16: thanks for that. I understand temp and pressure are can affect the out put also. But it wouldn't account for the 3-400 yard confison I'm seeing.

Next time I shoot I will see what it takes to get on target @800. Then shoot a group at 400 with with out changing the scope? Then messure the differance, Or should I adjust to 400yd zero
Reply With Quote
  #13  
Old 07-08-2013, 11:11 PM
Silver Member
 
Join Date: Sep 2009
Location: South Dakota
Posts: 381
Re: .243win 75g vmax help

Quote:
Originally Posted by 1tonpower View Post
Brass 16: thanks for that. I understand temp and pressure are can affect the out put also. But it wouldn't account for the 3-400 yard confison I'm seeing.

Next time I shoot I will see what it takes to get on target @800. Then shoot a group at 400 with with out changing the scope? Then messure the differance, Or should I adjust to 400yd zero
After you dial up to see what it takes to get to 800...you want to dial back down and see what it takes to be on point at 400.

If you cant find a velocity that matches the trajectory at BOTH distances, then your BC is slightly off.

Either way, the only explanation I can come up with for your 3-400 yd adjustment being so far out of wack, and still being on target at 500, is your turrets aren't tracking correctly.

What atmospheric conditions are you using for your program?
The only way I can figure it taking 7moa at 500 yds, is if your atmospheric pressure is way high, or if you're velocity isn't really as fast as your 400 yd dope says it is.
__________________
"We do not rise to the occasion...we fall to the level of our training."
Reply With Quote
  #14  
Old 07-09-2013, 05:53 AM
Silver Member
 
Join Date: Nov 2011
Posts: 231
Re: .243win 75g vmax help

I had the atmosphere option turned off. Next time I shot I'll turn it on.
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes


Current Poll
How Many Different Cartridges Do You Reload For?
ZERO, all factory ammo - 8.04%
329 Votes
1 - 2.83%
116 Votes
2 or 3 - 14.61%
598 Votes
4 or 5 - 20.45%
837 Votes
6 or 7 - 14.61%
598 Votes
8 or 9 - 8.87%
363 Votes
10 or more - 30.59%
1,252 Vote
Total Votes: 4,093
You may not vote on this poll.

All times are GMT -5. The time now is 07:21 AM.


Powered by vBulletin ©2000 - 2014, Jelsoft Enterprises Ltd.
Content Management Powered by vBadvanced CMPS
All content ©2010-2014 Long Range Hunting, LLC