Problem with calcs for 4dof and strelok

rustyshackleford

Well-Known Member
Joined
Dec 13, 2012
Messages
349
Location
North Alabama
Ok, i am not sure just what you are calling bc calculator? 4Dof was designed for Hornady bullets and seems to work better than most apps for them. Most apps that i have been around when entering Hornady bullets, the bullet does not fly as well as the output suggests.

Look at hornady’s page on actual BC values and you’ll see why.
 

Xescane

Active Member
Joined
Mar 1, 2020
Messages
41
Location
Idaho
The only thing that can make it off this much is the zero is no where near close or your scope is not tracking anywhere near what it should. You need to double check your zero and do a tall target test to make sure its tracking properly.
That's the plan. I brought it back to zero for elevation and windage and will be hitting the range this afternoon
 

jgs8163

Well-Known Member
LRH Team Member
Joined
Sep 27, 2011
Messages
827
Location
Southern Arizona
That's the plan. I brought it back to zero for elevation and windage and will be hitting the range this afternoon
Change the app to MIL and disregard what the turret says. Just count the clicks needed to achieve MIL elevation. As a prior post said “I bet you have MIL turrets on a MOA scope.” If the app matches at Mil to the clicks needed you then you’re on the right path.
 

Steve gavette

Well-Known Member
LRH Team Member
Joined
Jun 22, 2019
Messages
123
Location
Glendale, AZ
There is just no way for the correction for that bullet at 900 yds is anywhere near 12. The scope is wrong. Wrong turrets, tracking, whatever. Vortex has lifetime warranty. Call them.
 

LRNut

Well-Known Member
Joined
Dec 4, 2004
Messages
139
Location
Arizona/Colorado
Humble suggestion that you research "Station Pressure" vs "Barometric Pressure".

.

Weather stations report barometric pressure corrected to sea level, which I have never understood. But 4100 feet doesn't make that much of a difference; my house in CO is at 8750 and the difference at 720 yards is 3/4 to 1 MOA.

Also, there is no way a 300 WM requires only 12 MOA at 900 yards.
 

Pro2A

Well-Known Member
Joined
May 23, 2009
Messages
266
I can certainly give it a try. Here a question. When it asks for the sight height on which end of the scope do you measure this? since I have a 20 moa rail on the gun the front and back are different.
Measure bore-scope center line at the vertical center of the turret. That's where the adjustments are ticked off, and is roughly an average of the objective and ocular points on an angled mount.
 

Doozy

Well-Known Member
Joined
Aug 2, 2017
Messages
72
Location
Colorado Springs
Humble suggestion that you research "Station Pressure" vs "Barometric Pressure".

.


Ding-ding-ding!

You have to learn that air pressure often gets adjusted when the primary purpose is for weather; you're using the wrong measurement. ...Though, I'm not sure this will fix your problem entirely because you have a big discrepancy going on. I hope you figure it out.
 

Pro2A

Well-Known Member
Joined
May 23, 2009
Messages
266
You said no wind, but are hitting 1.25 moa left--- is your scope/reticle plumb?
Scope/reticle cant/rotation, just like rifle cant/tilt, causes more horizontal error than vertical at deviations just off vertical, growing in proportion until vertical and horizontal are equal at 45deg where vertical becomes more pronounced than horizontal to 90deg...3 o'clock or 9 o'clock. Should your cant be anywhere near the 45deg, you should put more shims under your shorter leg (R or L...the center one will cause vertical tilt).......or put the rifle away until the alcohol buzz is completely gone. :) :) :)
 

jgs8163

Well-Known Member
LRH Team Member
Joined
Sep 27, 2011
Messages
827
Location
Southern Arizona
Here’s the MIL DATA for you. This load is almost identical to what your shooting. This is a 100 yards zero. Good luck and let us know what you discover.

8C3D2A5F-5967-49CD-84F8-F89A81034F4E.png
8A1B4373-BF77-45E0-BAA4-D5A04498A89C.png
 

Xescane

Active Member
Joined
Mar 1, 2020
Messages
41
Location
Idaho
Change the app to MIL and disregard what the turret says. Just count the clicks needed to achieve MIL elevation. As a prior post said “I bet you have MIL turrets on a MOA scope.” If the app matches at Mil to the clicks needed you then you’re on the right path.
Actually. You may be right. I just did the math and if you count the amount of clicks and convert to mrads instead of moa it comes out to what I'm actually hitting with. Moa is 1/4 per click and mrad is .1 per click. So I may have a mrad scope with moa turrets. Damnit vortex!
 

jgs8163

Well-Known Member
LRH Team Member
Joined
Sep 27, 2011
Messages
827
Location
Southern Arizona
Actually. You may be right. I just did the math and if you count the amount of clicks and convert to mrads instead of moa it comes out to what I'm actually hitting with. Moa is 1/4 per click and mrad is .1 per click. So I may have a mrad scope with moa turrets. Damnit vortex!

Assuming that’s what it is they will make it right though. I actually prefer MIL. If you don’t want to remove the scope off the rifle then just ask them to send you new turrets. Good luck and let us know!
 

Primary

LRH Assistant
Here are some related products that LRH members are talking about. Clicking on a product will take you to LRH’s partner, Primary, where you can find links to LRH discussions about these products.

 
 
Top