Rifle Scope Mounting & Zeroing Guide

Rifle Scope Mounting & Zeroing Guide

If you are having trouble mounting a scope, you're not the first person, and you won't be the last. When you're new to the sport, all the numbers and torque settings can make it seem like it's bigger than Ben-Hur, but with a few little steps, it can be simply done.

Common issues

If you have run out of adjustment, it means that the scope is not correctly aligned on either axis. Points to look for are:

• Do I have a 10/20/30 MOA rail?

• Are the mounts securely fastened in their correct position?

• Have you been dialling the correct way?

• Are the rings and mounts you have good quality?

• Is the scope on the correct side? (mounted the right way up)

10/20/30 MOA rail

With a rail with MOA adjustment on it, sometimes when a scope (commonly with a 1" tube) with limited adjustment is placed on it, you can't adjust it down to zero at 100m. This is because the scope is not suited for this tilt in the rail. Small hunting scopes (3-9x40, 4-12x40, etc) run into this issue most purely just because they are designed to be hunting scopes and not used on a rail originally designed to aid in target use. If this issue affects you, check your rail and see what adjustment it has and look to reduce it if you can't zero on it.

Are the mounts securely fastened in their correct position?

Making sure the mounts are located in their correct position is essential. Without this step, the scope won't be centred down the barrel, and you will not be able to zero the scope. Another issue you can run into is crunching the scope. Rings are precision-made to be 100% in line with each other, and if you don't put them on the right way, the scope will sit awkwardly in the rings and become crushed when the top rings are tightened down. So, with a dovetail mount, ensure the two sides of the mounts are securely fastened on both sides and sitting flush on the dovetail. If they don't, it could mean you don't have the correct rings for your rifle. With a picatinny rail, ensure the lugs are sitting correctly in the gaps and that the base of the ring & the clamp are sitting flush with the correct torque settings. 

Have you been dialling the correct way?

A common mistake we see on zeroing the rifle scope is dialling the incorrect way. On a rifle scope, the adjustments to zero the scope are to move the Point of impact (POI) or the Bullet hole to the Point of aim (POA) or where the reticle is aimed. For example. Assuming the reticle is in the centre of this target.

You will need to make a 2.5MOA adjustment to the left and a 1.5MOA adjustment up. This will move your POI to match the POA. If you try to adjust the reticle down to match the impact points, or move 2.5MOA right and 1.5MOA down, you will keep moving further and further from the centre of the target.

Are the rings and mounts you have good quality?

Good quality equipment can be the difference between a good day shooting and wanting to snap your gun in half. With rifle equipment needing to be precision-machined in order to line up to be accurate, if your equipment is sub-standard, it means that the scope may not be in line with the bore and will require you to adjust the scope to correct for this. Needing some adjustment in the scope is normal, but needing to adjust to the point where you can't go any further means that there could be an issue with your mount quality. 

Is the scope on the correct side? (mounted the right way up)

This one sounds like a no-brainer, but you'd be surprised by how easy and how often scopes are incorrectly positioned. The easiest way to mitigate this is to determine the eye piece and the elevation turret. The eyepiece will have a diopter adjustment on the end of it to focus the reticle to your eye. The eyepiece, as the name suggests, will be the way you look through the scope. Another easy way to tell is that instead of zooming into the target, the targets seem like they have been zoomed out quite a bit. It means your scope is backwards. The elevation turret needs to be upright, as it will have more adjustment than the windage turret and will allow you to make further corrections. The elevation is easy to tell because it will have a measurement (0.1MRAD, 1/4MOA or 1/8MOA) and the word up with a little arrow denoting which way to spin the turret to move the POI up.

Having the scope on its side will be like having your car sitting on its side; you can sit there and look through it, but you're not going to get far.

Summary

I hope these tips have helped you zero your scope and continue shooting. If it hasn't, please contact the team at Optics Warehouse, and they can help you further in troubleshooting your issue.