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Can someone plot a trajectory for me?

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28 March 2004, 04:26
.22 HORNET
Can someone plot a trajectory for me?
I have Speer's newest manual but it doesn't have the latest 33gr TNT hornet bullet in it. The web site lists a load of 14.0 gr Lil"gun at 3068fps. The B.C. is .079

Could someone plot a trajectory at 50, 100, 150 yrds.

Thanks
28 March 2004, 05:30
Savage99
That BC must be wrong. Could it be .179? What's your sight height?

Go to www.huntingnut.com and download "Pointblank" and figure it out.
28 March 2004, 05:39
Tailgunner
Assuming a 1.5" above bore sight centerline, 3070fps, 100yd zero, and that your giving the correct BC.

at 050yd your flight path will be -0.03, 2484fps at 50yd

at 100yd your flight path will be +0.00, 1970fps at 100yd

at 150yd your flight path will be -2.26, 1530fps at 150yd

Max height of flight path +0.21 @ 76.6yd

Using a 50yd zero

at 100 you will be +0.06

at 150 you will be -2.16

Max height +0.26 @ 78.1yd

Using a 150yd zero

at 050yd you will be +0.72

at 100yd you will be +1.50

Max height +1.51 @ 96.1yd

Using the PBR methiod, with a +/- 1" flight path, Zero at 135.4yd, +1.00 @ 89.1yd, -1.00 @ 152.5yd

Your actual results will vary, actual test firing is required.
28 March 2004, 06:14
.22 HORNET
Thanks Tailgunner,
Wow, with that terrible B.C. this bullet really drops off like a water balloon! I made up some loads with them and they really shot good. However, I think I'll stick with the 40gr v-max. Thanks again for your help.
28 March 2004, 06:45
Savage99
Indeed the Speer site lists that bullet at a Ci of .079!



www.speer-bullets.com/html/ballistics/detail2.asp?name=1014



Hornady has a .35 gr at .109
28 March 2004, 11:55
Wstrnhuntr
Quote:

Assuming .......... and that your giving the correct BC.







No such thing mate! Look closley and youll find that given BC's vary between all bullet manufacturers and that likewise their ballistic data are geared toward THEIR interpetation of said ballistic co-efficent. In other words, for the most accurate translation of Speer bullet trajectories you are best off using their data and likewise with other manufacturers.
28 March 2004, 12:37
Tailgunner
With no sight style, desired zero range, basic elevation, or hi/lo trajectory given, I had to make some assumptions.

BC varies with bullet syle true, but with any given BC and MV a curve can be plotted, as at that point it's a streight forward math problem.

I also used a MV close to what he requested (book), but that dosn't mean it's the MV he's actualy getting out of his rifle.

Also re-read my last line, "Your actual results will vary, actual test firing is required."