If you look at several different "books", you will see different results posted.
I interpolate from multiple books data and move forward carefully watching the chrony and looking for signs.
See antelope sniper's response above.
Add that you have a different measuring device and distance from the barrel also, and EVERY barrel is different.
jmho
Tim

PS- Yes there are slow and fast barrels. Each must be treated as the individual that it is.

Last edited by michiganroadkill; 09/02/15.
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