Range Report Range data not matching Bullet Flight software.

[Cswanson]

I will start off by admitting that I am new to long rang shooting although the target I was engaging probably wouldn't be considered long range to many of the experts that are on this formum but we all must start somewhere right.

Rifle Used: .308 Remington 700 5R w/24" barrel (1:11.25), Vortex Razor HD w/20 MOA Rail, zero at 100 yards
Ammo: Hornady 168 gr A-Max w/46 gr Varget, COAL: 2.84" (10 Shot Average Muzzel Velocity: 2777fps) Chronograph set 10' from the barrel
Software: Bullet Flight (iPhone)
G1 BC information was pulled from the bullet flight software at a value of 0.475.
Temp: 87.5 (All reading below from Kestrel)
Pressure: 29.46
Altitude: 418'
Wind: 3mph from 1 o'clock
RH: 63.7%

Target: 8" square plate ranged at 480 yards.

The bullet flight software indicated that I needed to dial -2.8 mil. I was engaging the target with -2.2 mil. Four consecutive shots in a row. I can understand being +/-0.1 mil but 0.6 mils?

I used the BC calculator from drop function with the following values:
3.64*4.8=17.472"
17.472*2.2=38.44"
When I input 38.4" drop at 480 yards along with the other information it tells me that my G1 BC should be 1.172. I don't know much but I think that is impossible for a .308?

What am I doing wrong? Any help would be greatly appreciated.

Thanks in advance!
Cameron

 

[Cswanson]

Re: Range data not matching Bullet Flight software.

I don't know if it is reliving or not but I was shooting the entire distance across water.

 

[Cswanson]

Re: Range data not matching Bullet Flight software.

Angle: 0 deg
Scope center to bore center: 1.9"

 

[TRAAV]

Re: Range data not matching Bullet Flight software.

sounds like you have something jacked up in your programing. the 2.2 mil sounds right to me. I ran the numbers on isnipe and came up with 2.0 with litz g7

 

[BapZander]

Re: Range data not matching Bullet Flight software.

It looks to me around 2.8 is correct...

But that being said, have you done any scope calibration tests? I would find it hard to believe that it was that far off, but stranger things have happened.

If you set up a 36" yardstick or tape measure vertically at 'exactly' 100 yds, that should be 'exactly' 10 mils. Aim the scope at the bottom of the yardstick, then crank 10 mils on the scope - it should be right at the top.

 

[Cswanson]

Re: Range data not matching Bullet Flight software.

Thank you for the feedback. I will give the yard stick a shot and see what I come up with.

 

[BapZander]

Re: Range data not matching Bullet Flight software.

Actually - if you zero'd at 200 - 2.2 mils would be right.

What distance is your zero at, and did you put the same zero range in the ballistic app?

 

[TRAAV]

Re: Range data not matching Bullet Flight software.

I stand corrected. I read it as you were shooting 400 yards. not 480. at 480 yards 2.8 is correct.

 

[Cswanson]

Re: Range data not matching Bullet Flight software.

I currently have the rifle "zeroed" at 100 yards.

 

[Cswanson]

Re: Range data not matching Bullet Flight software.

I am going to try and make it out to my range today and box test the scope using both the yard stick and a large target like it is refferenced in the training video here on Snipers Hide.

I would like to think that my scope should be accurate given I paid 2K for it. From what I have heard Vortex delivers a stand up product and customer service.

Thank you all. Cameron.

 

[Cswanson]

Re: Range data not matching Bullet Flight software.

I went out to the range today and come to find out my rifle was NOT zeroed at 100 yards. I was reading about 0.3 mils high at the target and about 0.2 mils to the right. I re-zeroed the rifle and then box tested the scope by adjusting the elevation 10 mils up and it measure roughly 36". I also check the reticle versus the elevation and windage and everything checked out perfect.

Now I need to double check my 480 target to see if my elevation issue has been resolved.

Thanks again everyone for the help.

Cameron

 

[Mountain Shooter]

Re: Range data not matching Bullet Flight software.

I have encountered having bullets impacting High on target while shooting across water also. Dont know why but it happened to 4 of us shooting four different rifles. Rifle data was spot on shooting at a target the same distance across land. 2-3 MOA high which is basicly what you were seeing.then again you said your zero was off. Keep up updated on how the second trip went. On our day the water was way cooler than the air. Maybe evaportation lift???

 

[Cswanson]

Re: Range data not matching Bullet Flight software.

I plan on going back out to my range this weekend. I will update you on my findings.

 

[Cswanson]

Re: Range data not matching Bullet Flight software.

I went back out to the range over the weekend and my rifle seems to be pretty close (+/-0.1MIL). I guess at the end of the day nothing will beat an actual dope.

 

[was21]

Re: Range data not matching Bullet Flight software.

Yeah , it's amazing how that thing called 'reality' beats that thing called 'theory' every day ! HA!