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Old 22nd August 2014, 01:57 PM
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pirellip pirellip is offline
Join Date: Jul 2010
Location: Toronto, Ontario, Canada
Posts: 38

Originally Posted by Adam View Post

Shimming of your scope is irrelevant for trajectory calculations. Shimming affects the angle of the scope tube, to compensate for lack of adjustment range or optical centring. All that's relevant to Chairgun is the zero range and the height of the sight line above the bore. The sight line being the line through the centre of the reticle which goes through the axis of the erector tube, not the axis of the scope tube.
Hi Adam,

Yes you are correct that the scope has no effect on the pellet's path through the air! I had just recently learned this, but didn't recall it - never was all the proficient in school!

As I'm learning about the mechanics of how a scope works, and the relationship between your sight picture and the pellet trajectory, I'm correcting MANY of my previous misconceptions - eventually I'll remember them all!

In Canada, we have a 'blended' set of rules that we've developed from taking bits and pieces from other countries. With respect to Hit Zone sizes, we follow this approach:
1/4" - up to 15 yards
3/8" - up to 20 yards
1/2" - up to 25 yards
3/4" - up to 35 yards
1.0" - up to 45 yards
1.25" - up to 50 yards
1.50+" -up to 55 yards

However many of us shoot under the WFTF format, so our scope setup is pretty important, as we still try to hit the same stuff at sub 12fpe as others are shooting at with sub 20fpe.

But I digress! I'm off the NZ zon Monday for the big match, and have been warned about 'Windy Wellington' but just haven't been able to practice in the wind - so I'm hoping that I can learn *something* about where my pellet is going to land by studying ballistics software!

Hoping I could get some feedback on this software's ability to do this since I can't test it's predictions out myself.

Yes, I am aware of the Chairgun Mobile App, but for some reason it doesn't display any data past 38 yards on my phone (and I've tried MANY things to solve this)
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