12 inches low at 20 yards is how low at 100?
 

I still have to order my pos align inserts, but they come in different sizes based on how much you need to adjust, and specify being off so many inches at 100 yards. I am 12 inches low at 20 yards, so how many inches low would that equate to at 100 yards? It is a Mossberg 500 with rifled barrel.

Thanks!

RE: 12 inches low at 20 yards is how low at 100?
 

How high is the center of your scope above the center of the bore and how far apart are the rings?Knowing these measurements will allow a calculation to put you in the ballpark.Using basic geometry 12" at 20 yards converts to 60" at 100 yards but that does not take into account the height of the crosshairs above the bore or the distance between the rings.

RE: 12 inches low at 20 yards is how low at 100?
 

thats a big amount at 100 yards... a basic equation would make it60 inches at 100 yards

RE: 12 inches low at 20 yards is how low at 100?
 

The scope center is roughly 2 1/4 inches above the bore center, and the rings are roughly 2 3/4 inches apart.

RE: 12 inches low at 20 yards is how low at 100?
 

Sorry but my calculator with geometric functions died.Perhaps someone else can do the calculation for you.

RE: 12 inches low at 20 yards is how low at 100?
 

At 60" that would be putting the bullet in the ground at 100 yards! With 1/4" intervals, that'd be 240 clicks up! You said you are getting posi-line inserts. Are you sure something else isn't wrong?

RE: 12 inches low at 20 yards is how low at 100?
 

Must be something else! I'm giving it to my buddy to sight in/fix. He knows a lot more about guns than me!!!

RE: 12 inches low at 20 yards is how low at 100?
 

The crosshairs being 2-1/4" above the bore is certainly a contributing factor.I have seen more than one gun with see through mounts that could not be sighted in without shims.