Help with boresighting

[bolus]

Im trying to boresight my 50 to minimize ammo at the range to set up the zero. Im using a laser boresighter from sitelite that has a nice program where you can give the program details about the rifle and then what distance you have available and it prints a custom target to use for boresighting

http://sitelite-lasers.com/BTS.html



The problem is if I zero for 200 yards im nearly bottoming out the scope. I only have 4 more MOA adjustment up when I zero with this. (the scope has 65 MOA in elevation adjustment).





I have a feeling Im doing something wrong. Do I need a shim for the base of the rings?

Read More

 

[Joe13]

Im trying to boresight my 50 to minimize ammo at the range to set up the zero. Im using a laser boresighter from sitelite that has a nice program where you can give the program details about the rifle and then what distance you have available and it prints a custom target to use for boresighting

http://sitelite-lasers.com/BTS.html

View attachment 290664

The problem is if I zero for 200 yards im nearly bottoming out the scope. I only have 4 more MOA adjustment up when I zero with this. (the scope has 65 MOA in elevation adjustment).

View attachment 290665

View attachment 290666

I have a feeling Im doing something wrong. Do I need a shim for the base of the rings?

I was going to say if everything else is as it should be then a shim would be where I would go.

 

[NWCustomFirearms]

I'm with Joe, as long as everything is good, scope mounted properly and not by the box store geniuses, rings lapped and everything then a shim would be the way to go.


No offense if you work behind a gun counter of a large store, it's a joke

 

[bolus]

I assume a shim would go between the rail and ring. I dont really want to cut a aluminum can and use like I see suggested frequently. Are there custom made shims for such a purpose?

 

[Joe13]

I assume a shim would go between the rail and ring. I dont really want to cut a aluminum can and use like I see suggested frequently. Are there custom made shims for such a purpose?

I would think so.

One other thing I have read is to try swapping the back ring to the front and visa versa. Only takes a couple min and I have heard of it fixing 'some' people's issue.

 

[Member 5605]

I assume a shim would go between the rail and ring. I dont really want to cut a aluminum can and use like I see suggested frequently. Are there custom made shims for such a purpose?

I went to harbor freight and bought a set of cheap feeler gauges. I knew the .010" in the set is brass. .020" is 'roughly' 20MOA at 100y.

Leupold customer service told me that. I doubled up on the .010" shims and made my own 20MOA base

Leupold sells shims if you don't want to make your own.

 

[Member 34319]

Remove that brake and ensure the laser is positioning itself off the bore not the end of the brake that may be uneven.

Center your scope back to factory zero.

Remove scope rings and base. Clean them all and inspect for problems.

Retry.

I would say there is something up with the way the laser sight is aligned with the brake causing the issue though.

As for the scope bottoming out, your scope or something is very off spec to be that far off trying to zero at 50 yards.

In theory, with scope zero'd to factory zero, and mounted to rifle, the scope should be pointing at the cross hairs and the barrel should be pointing pretty close to where the dot is on your print out.

 

[bolus]

I found 2 shims in my extra's box (they must have come with something I bought since I dont remember having them). They are 2 u shaped shims that fit over the raised part of the rail. 0.01in so it did give me the extra 20 MOA and it is much better.

Thanks guys.

Reno, I'll try that with the scope on another rife to see if it's factory zero is close. I also considered the brake being the issue

 

[Member 34319]

Reason I say that is unless you purchased inexpensive chinese knock off rings and such, there is either something really wrong with your scope, rings, or base to have to bottom out your elevation for a 50 yard set up like this. Seeing the Vortex, and knowing it is on a 50, I doubt you have inexpensive rings on it.

Shimming shouldn't be required is what I am getting at.

If the brake isn't to fault then I would say the laser is.

Find yourself a straight object like a wall. Place the laser in a non tapered object like PVC or something that can be set parallel to the straight object and see if the laser is straight or not.

You could also get a piece of wood or tubing .5" in diameter and stick it down the bore to see if your brake is off center with the bore. I know some manufacturers design breaks to be off center to allow gas to escape in one direction faster than the other.

Another thing to test would to leave the laser in and lock down the rifle. Mark the lasers location at a certain range. Then rotate the laser, if it is off, you will get a nice circle on your target. Find the middle of the circle and you got your bores location.

Also does the base have any MOA built in? How about the rings?

 

[Ura-Ki]

Seems your pretty Crafty with these things, you might see how the shim set up works out after removing your break. If you don't need shims, then all should be good to go, if you do, then you could shave your mount(s) to get a taper. We used to do this trick with our Designated marksmen rifles to get an exact zero for each individual rifle. We found the a -20 moa rail didn't always work for an exact zero! what works nice is to hot glue some 100 gr it sand paper to the top receiver, and start working it to cut a front biased taper. Once you get close, switch to 220 grit and take it down a little more. Take your time, and check often, and you can get it near perfect! Make sure to lock tight the mount and screws once you are ready to shoot!

 

[Ura-Ki]

Check what RENO911 recommends FIRST!

 

[Velzey]

Aluminum soda cans are great shim material!

And is that bore site seating in the MB or the rifle bore?

 

[bolus]

The rings are Badger Ordnance max50. Supposedly matched and serialized so I doubt they are the issue. Hopefully Im getting what I paid for them.

I used a 1/2" brass tube in the bore and the brake seems to be centered very well. Cant really tell by the pic but I took one so might as well show it. But the space around the end of the brass tube seems an even 0.02" all around




Im hesitant to remove the brake though. It does not have a crush washer so Im not sure how it is on there and Im not sure I could get it back clocked and tightened appropriately.

The sitelite laser seems accurate. It has done well in other rifles and the laser point does not change positions spinning it in the barrel.

So assuming those are fine that leaves the rail and scope. perhaps it is a -20 MOA rail

I appreciate everyone's input

 

[bolus]

Aluminum soda cans are great shim material!

And is that bore site seating in the MB or the rifle bore?

the laser goes into the bore with a properly sized O ring. but only one point of contact with the barrel. The alignment is definitely based on the position of the opening to the brake

 

[Member 34319]

Even if it was a 20 minute rail for a mount. At 50 yards that would only offset the scope by 10"s. So if your scope is somewhat straight and true when centered back to factory, your point of view should be 12"s above the point of the laser at 50 yards, guessing that your center line for your optic is roughly 2"s above the bore line. Probably more with that fifty!

Do me a flavor and measure your sight height. Then count your scopes elevation clicks from one end to the other. Divide by two, then from one farthest end go to that number. IE 120 clicks, go all the way down, then up 60. Do this for your windage as well. This should be center for your scope.

Also I recall shooting your Ruger that was off, I recall you saying you laser sighted it? Same system? You were off by close to a foot when I walked it in that day. Just saying...

 

[Joe13]

Eh we used to just stand close to the target and back up and adjust as we went - y'all have gotten all technical on it and confused the poor thing

 

[Member 34319]

Eh we used to just stand close to the target and back up and adjust as we went - y'all have gotten all technical on it and confused the poor thing

True this, but I have seen a guy waste $300 in 50cal ammo trying to sight his scope in. Only to realize he blew out the scope, likely after the 1st couple of shots.

 

[jbett98]

The easiest way to center a scope back to factory zero is to place it tight against a bathroom mirror and look through the eyepiece.
Adjust the knobs till both sets of cross hairs line back up together.

 

[bolus]

Sight height is 2.47in Already calculated that one. You gave me an idea with the ruger. since we know it is close to zero at ~100 yards I tested the laser sighting tool on it and it is pretty close to the where it should be on the paper target. So the laser boresight seems fine.

I factory centered the scope. with the 0.01" shim still in place it is pretty close to where it needs to be on the paper target (I dont have 50 yards on my property to test without my neighbor's calling the police it so Im using the calculated paper target. the factory center also lines up with the marks on the turrets where the center should be.

Just a small adjustment in both windage and elevation to get it back to where it was. what ever the issue is seems to be 20 MOA off

Probably just need to go shoot it now like Joe13 says.

I probably would have remembered my trigonometry better in highschool if someone said it would help me learn about riflescopes.

 

[pakrat57]

Sorry if this sounds stupid, but if you just put a shim under one end isn't that going to tweek the scope.