New Drag Model for Airgun Slugs

[ballisticboy]

My Norton did the same and removed the setup file but you can tell it to put it back. I have scanned the instaled programs and there were no threats found. i think Norton objects because there have been so few users who have downloaded this file.

[rsterne]

I don't know how to bypass Norton....

Bob

[rkr]

So if I understood this correctly this model is for flat base slugs that are now produced commercially. Does this model work with rebated boat tail bullets and gas check tails?

[rsterne]

Yes, for flat based slugs with a Meplat of about 50-60%, as are now produced commercially.... It is not intended for use with a rebated boattail, but should be close with a gas-check IMO.... I think if will probably be close for a RBT than using the G1 model, however.... The big difference is that it predicts a lower drag between Mach 0.8-0.95 (900-1070 fps) than the G1 model.... which is consistent with what we are seeing in testing....

Bob

[rsterne]

Thanks to Miles I was able to get EasyBC running on Windows 10.... It is an easy to use program, giving 3 different ways to find your BC, POI change, time of flight and MV, or the more traditional two velocities separated by a known distance (which works with LabRadar too).... It has quite a few drag models which are usable for airgunners, including Miles new proposed Slug model (which he calls SLG_o).... On first blush, it would appear to be better for slugs than using G1, so you might want to give it a try.... and don't be afraid to push your slug velocities into the mid 1000s, if they are still accurate for you at that speed.... Don't forget to put in your temperature, barometric pressure (correct for your altitude, and critical), and relative humidity (less important).... If you are shooting at a couple thousand feet and don't use the correct pressure you will get a BC that is much higher than it actually is.... 

Bob