Recent content by Legoman

Thanks Chusslove. From that, I'm guessing that based on my values above, I'd get: A_North = -2 * V_North * V_Earth * sin(lat) A_North = -2 * 4000 fps * 7.27 x 10-5 rad/sec * sin(36.728) A_North = 0.3478 rad-ft/sec^2 "Up" A_East = -2 * V_North * V_Earth * sin(direction of fire) A_East =...

OK. At the equator the effect is 0, but it gets bigger as you near the poles... That makes sense. So, if I fire at a direction other than north or south, will I have multiple angle vectors to take into account? If I fire East for example, I'd be at 90 deg to the axis of the earth. But...

I still don't know the direction issue, but I think I may have figured out part of the math issues. I was using the linear velocity of Earth instead of the angular velocity. The angular velocity of Earth is 4.17 x 10^-3 deg/sec. Now the acceleration comes to: ac = -2 * 4.17 x 10^-3 * 4000...

OK, now I'm really confused. If the vecor is from South to North, then it's parallel with my velocity vector. The Sin of 0 is 0 so there'd be no acceleration due to this effect? I know that's not true... To me, the angular velocity vector should be "up". This would put the new vector to...

I'm at the same point I was when I put up the first post. The vectors are perpendicular. The bullet is going North, and the rotation is "East". Using the right hand rule, this puts the new vector straight up, which makes no sense... Using the data in my example, can someone show me how the...

I've looked at this, and it still doesn't make sense. If someone can help, I'd appreciate it...

Ok. That explains why I got such a big number... Thanks. Danny

I understand the concepts, I'm just having trouble putting math to it... I know that the velocity of the latitude I mentioned before (36.728 North) is 622.934 miles per hour (25000 mile circumference of Earth * sin (latitude) / 24 hours). 622.934 MPH is 913.6365 fps. 750 grains is 0.1071429...

I've been searching all over the web and on this forum for an answer, and I haven't found it (or I may have found it and not understood...). If this is a re-hash, I'm sorry... I'm working on some ballistics calulations for long range rifle shots. I've got pretty much everything worked out...