I bought a burris XTR2 with 90moa of total elevation so I was figuring on using 40moa of cant. 20 base, 20 scope ring. When i laser boresight the scope it maxes out before i get to center. It stops about 2 mils above center.
Rifle Scopes Question Zeroing a scope with 40 moa base?
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90 moa divided in 2 equals 45 up and 45 down.
40 moa shifts that zero point to make it 85 up and 5 down.
However if the zero wouldnt naturally be perfectly centered in the scopes adjustment range then you might run out of available elevation sooner than that. On a 0° base maybe your scope would give you 52 up and 38 down. Throw that on a 40 moa base and youre now at -2 down and 92 up, you would be lacking 2 moa to zero.
2 mils is 6.75 moa that you are low. Youve now discovered the issue with forcing your scope to the limits. Unless youre wanting to shoot ELR you wont need that much cant in your system.
Get rid of the 20 moa in your scope rings and youll be good.
Im guessing you have the burris rings with the adjustable inserts? Have you done the math to see if they are actually giving you the indicated amount of adjustment? Distance between the rings can influence that and give more than you might have expected. Bump the inserts down to 10 or 0 and you should be good, I would probably go for 0 cant in the rings myself. That with the 20 moa base will still give you 65 moa up (19+ mils available still which takes me to a mile) and 25 down.
If you have a one piece scope mount thats a bit more difficult to remedy, youll want to get a new one to replace it with.
40 moa shifts that zero point to make it 85 up and 5 down.
However if the zero wouldnt naturally be perfectly centered in the scopes adjustment range then you might run out of available elevation sooner than that. On a 0° base maybe your scope would give you 52 up and 38 down. Throw that on a 40 moa base and youre now at -2 down and 92 up, you would be lacking 2 moa to zero.
2 mils is 6.75 moa that you are low. Youve now discovered the issue with forcing your scope to the limits. Unless youre wanting to shoot ELR you wont need that much cant in your system.
Get rid of the 20 moa in your scope rings and youll be good.
Im guessing you have the burris rings with the adjustable inserts? Have you done the math to see if they are actually giving you the indicated amount of adjustment? Distance between the rings can influence that and give more than you might have expected. Bump the inserts down to 10 or 0 and you should be good, I would probably go for 0 cant in the rings myself. That with the 20 moa base will still give you 65 moa up (19+ mils available still which takes me to a mile) and 25 down.
If you have a one piece scope mount thats a bit more difficult to remedy, youll want to get a new one to replace it with.
yeah, that's a lot of cant.
some scopes can still zero, some cant.
how far do you plan on shooting? what caliber? do you NEED all that cant?
drop down to 30moa or 20moa and you'll be fine
some scopes can still zero, some cant.
how far do you plan on shooting? what caliber? do you NEED all that cant?
drop down to 30moa or 20moa and you'll be fine
Some scopes also really suffer optically when they’re maxed out.
20 0or 30 moa tails are a nice range.
20 0or 30 moa tails are a nice range.
It's on a 6.5cm and I was hoping to stretch it out a mile+ without hold over.
It's a single piece ADM so probably look for a 10moa base and keep the 20moa scope ring
I figured the 40 out of 45 was safe, guess not.
It's a single piece ADM so probably look for a 10moa base and keep the 20moa scope ring
I figured the 40 out of 45 was safe, guess not.
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Laser bore sighters suck. Tried one years ago and told me I couldn't zero with a 20 MOA base. Zeroed just fine when actually shooting it. Go shoot it and see what happens.
I'm with Rob, and also at what distance did you boresight? If it was close, for example 50 ft. the laser would be too low due to the height over bore offset.
This 1000% take that laser boresighter and throw it in the trash or just use it as a laser pointer. I just recently zeroed a Schmidt and Bender 5-25PMII at 100yds on a 338 Lapua with 50 MOA of cant I didn't think I was going to have enough but it did. One valuable piece of advice I got from Jerry who is the Schmidt and Bender Guru is to not leave the turret at zero when finished shooting he said when storing the rifle to go ahead and dial back up to the second revolution to take some pressure off the erector spring so that it would not stay compressed towards the bottom end of its travel. Makes a lot of sense and I am going to start doing that for any rifle scope that has an extreme cant with a hundred-yard zero.
Windage was dead on. It shot 12oclock high aboout 6 inches (didnt actually measure). Turns out Burris builds the scope zeroed for 20 moa rail so its more like 60/30. Although they didnt reccomend using the last 5-10% something to do with glass distortion.
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