LoadBase 3.0 with (Spin Drift) PC&PDA Ballistic Program

[Eaglet]

Originally Posted by canderson

Eagelet,

I am trying to grasp the basics of spin drift and Coriolis effect. Spin drift, I believe, is from the precession of the projectile. RH twist = movement from center of the gun to the right (as viewed through the scope). LH twist would be the opposite. The Coriolis effect (maximum effect) when the projectile is fired North or South (0 or 180 deg.). When firing to the north, the target is moved from the earth's rotation to the east (therefore the POI is to the left). If firing to the north a person would need to add the spin drift and coreolis correction. When firing a projectile to the south, I think the target will move to the left (POI is to the right)? So, the spin drift and the coreolis effect act on the POI shooting north and south? But is the cumulative effect of spin drift and Coriolis on the POI one direction firing North and another firing South(POI left for North & POI right for firing South)? All this assuming a RH twist barrel. Any comments or suggestions will greatly help the little squirrel running in my head. Thanks.

Chris

Chris, I think your little squirrel is running alright. Mine stopped a while ago.

You're right, the effects are accumulative. Spin drift is affected by the twist of the barrel, the properties of the atmosphere but has nothing to do with the rotation of the earth. Spin Drift will always displace the bullet to the right if it's a right twist barrel, regardless of the direction you're shooting.
On the other hand, Coriolis Effect has to do with your Latitude and the direction you're shooting. Producing two components, a horizontal component and a vertical component as shown here.



The horizontal component has to do with your latitude and is not affected by the direction you shoot; the vertical component is affected by the direction you shoot and where you are on the earth. Vertical component is maximized at the equator and minimized to zero at the poles. There is, though, zero vertical deflection when shooting due North or due South. As you would know, you'd hit high when shooting east and low when shooting west just following the same reasoning you used.

Man I hope we got this right!!!

[Eaglet]

Originally Posted by phorwath

Well thanks for keeping us informed. I expect Patagonia will notify LB2.0 license holders when the upgrade to LB3.0 is available. I hadn't heard anything before reading your thread/post.

They will, best costumer service I've seen!

[Eaglet]

Phorwath,

and all interested,

GOOD NEWS!

Once it comes out of the Beta Status, Patagonia Ballistic will FREELY make LoadBase 3.0 available as an upgrade to all registered users.

Those that for whatever reason don't want the upgrade, Patagonia Ballistics will still support LoadBase 2.0 while not updated.

Only new users or those getting a new device will require to purchase a license.

MORE!

LB3D ---> LoadBase 3.0 for Desktop is also IN THE WORKS!

[phorwath]

Good deal! I'm looking forward to it and studying up on the spin drift feature. I've already demonstrated the spin drift with my rifles at 1000 yds. I might as well factor it in with my ballistics software program. Thanks Eaglet.

[geargrinder]

What if I have a left twist barrel in Australia shooting North to South? Would the spin drift and coriolis then be down and right?

Eaglet, you are the king of gadget junkies.

[canderson]

Thanks Eaglet.

Chris

[Eaglet]

Originally Posted by geargrinder

What if I have a left twist barrel in Australia shooting North to South? Would the spin drift and coriolis then be down and right?

Eaglet, you are the king of gadget junkies.

That sounds like a compliment!