Message-ID: 
Newsgroups: AIRGUN.LIST
> 
> >Learn about why speed doesn't impress. Air resistance goes up at the
> >square of the velocity. Shoot for a projectal going max 850 and you'll
> >be headed pretty much in the right direction. Velocity means squat.
> >Retained energy is all.
> >
> 
> 
> Is there a point at which velocity way above 850 fps actually pays off?
Out
> on the web I found specs for an airgun claiming 98 ft/lbs in .25 cal.
> 
> Ballistics software says that a 17 grain .25 Beeman Laser would leave the
> barrel at over 1600 fps. Energy drops precipitously down to 27 ft/lb at
50
> yards, where velocity hits 850 fps. Then the curve mellows out, and you
stop
> losing energy so fast.
> 
> BUT. There's another ballistics program that claims to be better tuned
for
> airgun pellets. It doesn't do energy graphs, but it does draw trajectory
> charts. So I input the same starting data to see what it would figure
out.
> It paints a totally different trajectory. The one from above was a big
fat
> downward loop, shedding speed all the way. This other software shows a
nice
> flat trajectory, with lots of punch way out.
> 
> It's been my (limited, early) experience that my .22 trajectory is
flatter
> than the books say it should be. It seems more in line with results that
the
> second software predicts.
> 
> So I'm not arguing with Tim, but I ask if there's an effective compromise
> somewhere between 850 fps pellets and the sort of velocities that
> firegunners are used to...
> 
> -Michael
Where it all starts going wrong isn't with the charts, it's with the
accuracy. You will get to a certain point and the groups will open way up.
Heck even the firearms guys know that accuracy is better with standard
velocity .22's than higher velocity .22's in a lot of applications. that
may not hold true for all calibers but it sure does with most of the
airguns we've tested.
 Phil.P.
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