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aircube · Veteran Member

When zeroing a scope, if I measure say 27 yards and mark a line, do I stand on the line or is the end of the muzzle on the line?

aircube · Veteran Member

I know this is a fairly straight forward question, but can someone answer this for me?

when shooting a 30m target or zeroing a scope to 30m do you stand on the 30m line or does the tip of the muzzle go on the 30m line?

with a long barrel and depending on stance there would be about a metre/yard difference.

thanks

rsterne · Moderator

Realistically, the only time this matters is in competition.... The rules I have seen require the shooter to be behind the line, but the gun can project beyond.... Wink

If you're concerned about getting your trajectory to agree with ChairGun then just shoot at multiple distances until you get what you want.... There is so much difference in Ballistics Coefficients at different velocities (and therefore different distances) even with the same pellet you simply can't rely on charts for anything but a guide.... Rolling Eyes

If you measure the BC of a pellet at 900 fps and then again at 500 fps there can be a difference of 25-30% or even more.... That means that in actual shooting conditions the Ballistics Coefficient will change with the range from the muzzle.... Shocked

Bob

aircube · Veteran Member

thanks Bob, so using Chairgun for calibration helps, but its a rough aproximation?

I am assuming that for target shooting your feet have to be behind the line not the muzzle. Becuase for a short range like for pistols a yard could make a difference.

rsterne · Moderator

RE Chairgun, exactly right.... It will be very close, but not exact....

If you check out the rules for the target competition on this site.... you will find that all parts of the body must be behind the line, but the gun can stick past....

Bob