spin drift for 308 and .50 bmg

[*greenhorn*]

i have been looking all over the internet for spin drift calculations for the 308 and 50 bmg, i thought about buying the iphone program jbm ballistic but from what i see it auto calculates but doesn't display the adjustment, this may be wrong i have not seen the program in person. does any one have a relabel calculation, web page, anything? im mainly trying to understand spin drift and its calculation i am going to be shooting 308 out to 1000 yards and am looking at the Vulcan armament .50 bmg as well.

respectfully

 

[TallShot]

Re: spin drift for 308 and .50 bmg

IIRC, Lowlight did an excellent vid concerning this topic.....

 

[Luke]

Re: spin drift for 308 and .50 bmg

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[TallShot]

Re: spin drift for 308 and .50 bmg

And there you have it!

 

[The Mechanic]

Re: spin drift for 308 and .50 bmg

Respectfully you don't have to worry about it at only 1,000 yards.
This guy doesn't use it on his .50 so I won't use it on mine.
5 shot group

 

[*greenhorn*]

Re: spin drift for 308 and .50 bmg

his .50 looks like a Lamborghini lol,

i just wanted to know the equations im trying to get a deeper understanding, im learning from scratch and don't have anyone but you guys to ask, their so much crap on the net, or you input spin drift in yahoo and you see Michael Marelli taking his moms dress off??????? the local library don't have nothing because of the world we live in today, if you ask about a gun book they think you going to shoot someone

in the military they said "Macleod" shoot that and i did but i never understood why i could, "Kentucky windage" was my friend and i can adjust on the fly pretty fast. just trying to get a better understanding

 

[Redmanss]

Re: spin drift for 308 and .50 bmg

Since you're starting out, I recommend Bryan Litz's book "Applied Ballistics for Long-Range Shooting":
http://www.appliedballisticsllc.com/index_files/Book.htm

It will introduce and teach you a decent working knowledge on external ballistics. I would also focus more on wind calls and trigger control than spin drift calculations.

 

[Win_94]

Re: spin drift for 308 and .50 bmg

External ballistics: Gyroscopic drift (Spin drift)

I've found the calculation before, I just can't find it now.

 

[armydog]

Re: spin drift for 308 and .50 bmg

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Redmanss</div><div class="ubbcode-body">Since you're starting out, I recommend Bryan Litz's book "Applied Ballistics for Long-Range Shooting":
http://www.appliedballisticsllc.com/index_files/Book.htm

It will introduce and teach you a decent working knowledge on external ballistics. I would also focus more on wind calls and trigger control than spin drift calculations. </div></div>

He's right, I have the book and love it, it will give you a good understanding plus has software you can load onto a computer to give you an idea of spindrift at different ranges.

 

[Drifter™]

Re: spin drift for 308 and .50 bmg

On the link below, click on "Trajectory - Drift", then you can input your info and get calculated spin drift:

http://www.jbmballistics.com/ballistics/calculators/calculators.shtml

 

[Mute]

Re: spin drift for 308 and .50 bmg

Forget the spin drift and learn how to estimate range and read wind. If you miss a shot at distance, trust me, it will not be because you didn't calculate spin drift.