Hunting Washington Forum

Equipment & Gear => Guns and Ammo => Topic started by: leonpeon2 on November 08, 2021, 08:54:14 PM

Title: Help! Ballistic calculator.
Post by: leonpeon2 on November 08, 2021, 08:54:14 PM: Hello all!

I have been doing my research on ballistic calculators(BC) to give me a starting point.
Thing is I have entered the info on a few different BC and they are all over the place.
One says (@400 yards ) u 8.5 (strelok pro) another is up 5.25 ( ballistic buddy app) . One is 4.2 Another is up 6.17 ( hornady app) .
My thoughts were they all would be pretty close but it’s not.
Is there anyone on here that can give me a hand or correct what I’m doing wrong.

Input:
110 savage ultra light. 6.5 prc.
Bullet: hornady 143 gr eld-x match
Ballistic coefficient : .625
Zero at 200
Muzzle velocity 2960.
Using moa with .25 increments ( vortex scope)

Ask if you need more info.

Thank you in advance.

Leon
Title: Re: Help! Ballistic calculator.
Post by: Farmer72 on November 08, 2021, 10:15:15 PM: There is a chance they are using different environmentals (barometric pressure and altitude) if you didn't imput that info.
Title: Re: Help! Ballistic calculator.
Post by: jakeweb on November 09, 2021, 05:05:42 AM: Also the drag model could be set different, sight height as well
Title: Re: Help! Ballistic calculator.
Post by: headshot5 on November 09, 2021, 07:09:47 AM: Not really your original question but some things to think about.

How did you get your velocity? Chronograph or estimated based off a box of ammo?

The easiest way to get accurate data, would be to sight in at 200 yards, then shoot groups at 400+ yards without touching the dial. Measure up from your group to your point of aim. Use that real world number as trajectory.

Mess with the numbers in your ballistic calculator, like B/C (these are often inflated values) and velocity (depending on where you got your 2960 number) until you get a match on the ballistic calculator to match real world drops that you shot. This is easiest if you shoot a couple groups at different distances. Say at 400 yards, and 600 yards. That way you can match your ballistic calculator info at both 400 and 600 yards for trajectory.

Another thing to check is what (measurement) each click is in your scope ends up being. A lot of times they end up not being precisely .25 more like .257 or something like that, which will show at longer range.
Title: Re: Help! Ballistic calculator.
Post by: blackpowderhunter on November 09, 2021, 08:01:31 AM: my bet is some calcs are using g1 vs g7 for example.
good luck
Title: Re: Help! Ballistic calculator.
Post by: HUNT JR on November 09, 2021, 08:30:30 AM: I use the Hornady 4dof calculator and it has been pretty good for me. None of them are perfect though, always check the drops they give you at the range to confirm them. I wouldn't be so worried about how the apps are different as much as I would want to shoot to confirm which app is actually right.
Title: Re: Help! Ballistic calculator.
Post by: Mtnwalker on November 09, 2021, 09:24:40 AM: Quote from: blackpowderhunter on November 09, 2021, 08:01:31 AM
my bet is some calcs are using g1 vs g7 for example.
good luck

:yeah: should be around 4.5 moa at 400 with your info at sea level
Title: Re: Help! Ballistic calculator.
Post by: OltHunter on November 09, 2021, 10:06:58 AM: :yeah:

I'm seeing 4.5 as well on a 1.5" sight height at 4,000 feet.

I've found BallisticsARC very reliable. I tried the Hornady app and it was way off as well.
Title: Re: Help! Ballistic calculator.
Post by: leonpeon2 on November 09, 2021, 04:35:12 PM: Thank you all for your reply’s.
With the elevation I have always put zero since I’m just trying to get a starting point.

The muzzle velocity I got was from the box as I don’t have a chronograph.

With the g1/g7 I always select the g1 if I can.

I will have to measure my scope to barrel size and see that’s where I am off.

I plan to get to actual shooting when I can. Ammo prices are way up and the ammo is hard to find. At $3-4 a round I wanted to see how close I can get before I actually start to shoot. I like to do my research.
Title: Re: Help! Ballistic calculator.
Post by: HUNT JR on November 09, 2021, 04:50:21 PM: The only other thing is that G7 is going to be the better number to use is what I have always been told/done. Im not sure what the truth to this has been, but its worked for me.