Aaaaaaand the BC of the LYMAN 257420 bullet is……….
.129
At least at my velocities and altitude it is.
Got seriously BORED cause of all the rain and snow and cold and caught a slight break. Still overcast and cold but at least the rain stopped for a while. I went to a local mountain range and quickly set up my chrony and video camera and loaded a 74 gr Lyman 257420 bullet in the TD257 and blasted one downrange. Well, OK, 3 downrange till i got a good reading on my Chrony.
While my TD normally shoots at 900 fps from a 3200 psi fill, today in the 50 degree weather, i could only manage 890 FPS at the muzzle from her. At 55 yards away, the bullet zipped over the chrony at 841 fps which translates to a .129 BC.
So there you guys go. RC, RJ, DOUG, and anyone else interested in a 257 of any type, you’ve got your BC for the LYMAN 257420 Bullet.
I also checked my numbers against G7 Ballistics program and via Handloads.com and they both concurred with the BC i got.
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That ought to make for some good down range performance! 😀
That’s about 3x better than our best pellet. 👿
I wonder what RC’s .25 cal.s cast are coming in at from his modded AF Platform.
Mike
Thanks for the research buttface. Lol. I wish i had time to do all that testing but chasing these hogs takes up alot of my time.
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Tof,
I was using .137 that I got off of Handloads.com for a 72 grainer, but I did notice about a 6 inch error at 285 yards.
Thanks.
RC