BC question???

KansasHunter5 · 11-09-2005, 09:35 AM

Can anyone help me out and find me the Ballistic Coefficient of a Federal Preimium .243 100gr Sierra Gameking Boatail. I know this isnt important in the equation but the average velocity is stated at 2960.

Federal doesnt have it posted anywhere, and the box doesnt either. I need it to run the ballistic program to figure out long range trajectory.

Thanks.

Chris

KansasHunter5 · 11-09-2005, 09:40 AM

Found it at "Sierra"

What an idiot!!!

lol

stubblejumper · 11-09-2005, 10:22 AM

Of course your trajectory calculation will not be accurate without the actualvelocity that the load produces in your gun which can easily differ by over 100fps from manufacturers claims,or without a precise measurement of your crosshairs over the center of the bore.Even then it could be out several inches at 500 yards.

Ridge Runner · 11-09-2005, 11:57 AM

stubbles right, best thing to do is use a programm thats capable of figuring BC from trajectory and sight in say at 100 yds, then shoot at 350, then let the program figure BC for the bullet from the trajectory of your load.
RR

stubblejumper · 11-09-2005, 12:32 PM

Actually I prefer to take all the guesswork out by actually shooting at 100,200,300,400 and 500 yards.The tables and calculations have been out by several inches in some cases.

Roskoe · 11-10-2005, 07:23 PM

I have had pretty good luck with the Exbal program - which allows you to program in things like altitude, height of scope above the bore, barometric pressure, etc. The only thing from making it a more exact science is the "truth in advertising" factor when it comes to ballistic coefficients. It seems like Sierra tends to overstate theirs a little . . .

Got to actually shoot the bullet at distance.

eldeguello · 11-20-2005, 07:49 AM

Quote:

ORIGINAL: KansasHunter5

Found it at "Sierra"

What an idiot!!!

lol

I was about to suggest that you look at the Sierra site......