Friday, December 02, 2005
Clickity Clack
I was looking at a Central Texas Airgun Club website the other day, they have a nice simple Excel spreadsheet that calculates trajectory for field target. One thing that it calculates is the click value for a given distance. Clicks are a funny thing. Most scopes are rated for a number of clicks at a 100 yards to move the crosshairs a minute of angle (MOA). It is very common for the MOA to be equated to 1" since the value of a MOA at 100 yards is approximately 1.0472 inches. For most applications, 1" is a close enough approximation.
However, for us anal types, the difference can't be ingnored. For me, the only time it really matters is for Field Target competition. I have uses a computer program to calculate the trajectory of my rifle for years. Most programs will calculate the click setting for distance and the difference between 1" and 1.0472" can make a difference in the click setting of the turret. Albeit, the difference may only be 3 or 4 clicks at 50 yards which amounts to about the height of a pellet but, hey, it may as well be right. My Bushnell 6-24x scopes are 1/8 MOA which equates to .131" per click at 100 yards.
Not all scopes actually perform to the rated clicks though so it is important to check the scope to be sure it really is 1/4 or 1/8 MOA before using those values in a trajectory program. If you don't, the values may not match very closely to the program output. The old Burris 8-32x RA scope were pretty bad in that respect, I had two of them years ago and both were about 1/6 MOA. Most scope are usually pretty close to the rated value and it really only makes a difference if you plan to shoot competition or change settings in the field.
However, for us anal types, the difference can't be ingnored. For me, the only time it really matters is for Field Target competition. I have uses a computer program to calculate the trajectory of my rifle for years. Most programs will calculate the click setting for distance and the difference between 1" and 1.0472" can make a difference in the click setting of the turret. Albeit, the difference may only be 3 or 4 clicks at 50 yards which amounts to about the height of a pellet but, hey, it may as well be right. My Bushnell 6-24x scopes are 1/8 MOA which equates to .131" per click at 100 yards.
Not all scopes actually perform to the rated clicks though so it is important to check the scope to be sure it really is 1/4 or 1/8 MOA before using those values in a trajectory program. If you don't, the values may not match very closely to the program output. The old Burris 8-32x RA scope were pretty bad in that respect, I had two of them years ago and both were about 1/6 MOA. Most scope are usually pretty close to the rated value and it really only makes a difference if you plan to shoot competition or change settings in the field.
