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magic rifle or incorrect click values

quiksilverj

Sergeant
Full Member
Minuteman
Aug 20, 2012
311
66
virginia
Went to get some dope on my rifle today using federal gold medal match 175's and got the following data. so i was trying to get an idea of what velocity this might be and this is where i got very confused. using JBM to come up with a trajectory that looks close to this i end up with around 2750 fps which i don't think makes sense. i am shooting a savage 10-fp with 22 in barrel and a 1:10 twist. after trying to figure this out i am thinking that my click values on my scope could be off? will check this next time i go to the range. you guys have any ideas what else could be going on? also shot several rounds at each yardage with elevation being real consistent.


Temperature: 24.0 °F
Pressure: 30.40 in Hg
Humidity: 53 %
Altitude: 2625.0 ft

yds MOA
100 0
610 -14.5
750 -20.75
900 -27.5
1025 -37
 
thats not a perfect way to gauge velocity, but it is within a reasonable margin of error. I believe FGMM 175s are listed around 2600-2650 fps. The extra 100-150 fps you are showing could be caused my a multitude of things: barrel length (Federal might test with a shorter barrel), altitude (you could be higher than the test site), or simply a calculation error within JBM

I wouldn't sweat it, buy a chronograph if you really want to know its velocity
 
If that is your observed trajectory, then that is all that counts. I've seen stranger shit with ballistic calculators. But yes, 2750 is kind of fast for 175 smks. Would be really nice, but unlikely with factory ammo out of a 22" barrel.
 
theresnosuchthingasmagic_zps0321d937.jpg


Just go buy a chronograph. It's going to be one of my next purchases. If you plan on doing any sort of long range shooting then you're going to need more precise numbers.