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All Springer/NP/PCP Air Gun Discussion General => Air Gun Gate => Topic started by: Snaab9-2 on November 07, 2011, 08:49:20 PM

Title: Ballistic Coefficient of a BB?
Post by: Snaab9-2 on November 07, 2011, 08:49:20 PM

Just curiuos, anyone seen a figure or measured the BC of a BB?

Title: Re: Ballistic Coefficient of a BB?
Post by: rsterne on November 07, 2011, 09:55:52 PM

I found one for Beeman Perfect Rounds in .177 cal.... Chairgun lists the BC as 0.014.... I also found one for Gamo Rounds, listed at 0.018.... A steel BB would be less because it's lighter.... should be about 2/3rd the above values, so maybe 0.010 to 0.012....

Bob

Title: Re: Ballistic Coefficient of a BB?
Post by: Snaab9-2 on November 08, 2011, 06:36:06 AM

Thanks Bob - very interesting.  So a steel BB has the BC of around a wadcutter or a pellet with a poor BC... intersting.  Those Gamo rounds actually carry their velocity fairly well...

Title: Re: Ballistic Coefficient of a BB?
Post by: aack73 on November 08, 2011, 06:41:13 AM

if you have a chrony you can calculate it. ;D

Title: Re: Ballistic Coefficient of a BB?
Post by: Earl on January 10, 2021, 12:36:59 PM

Quote from: rsterne on November 07, 2011, 09:55:52 PM

I found one for Beeman Perfect Rounds in .177 cal.... Chairgun lists the BC as 0.014.... I also found one for Gamo Rounds, listed at 0.018.... A steel BB would be less because it's lighter.... should be about 2/3rd the above values, so maybe 0.010 to 0.012....

Bob

OK, I will use 0.011 for a BB at 500 fps.
How much does the BC change at 275 fps muzzle velocity?
Thanks Bob