cz 527 shimming

[Michael]

Went to sight in my new cz 527 and had an issue. I started at 40 yards and set it for 3 inches high, went back to 100 yards to get it at an inch so i could go back to 200, and at 100 the bullet was about 4 inches low with the scoped max in elevation. I was shooting hornady v max 40 grains. From what I have been taught you will need to shim the scope, am I right or wrong? Does anyone have any suggestions on what i should do to fix this problem?

Michael

[wirelessguy2005]

We need a bit more information to make a proper diagnosis. Are you using the factory CZ rings or another brand? Are you sure that the rings were tight? Have you used the scope before or is it new and untested?

[Bill K]

I would ask simular question, is the scope new or one you had on another rifle and did not reset/center the crosshair/retical ?
If that is the case, then reset them and try again, then if that does not cure the problem, check for shimming. Bill K

[Michael]

they are Cz's rings yes i checked to make sure they were not moving and were tight. It is a brand new bsa 4x16x40 mil dot just out the box never been used. I have a bipod on the gun so it was a steady rest.

[wirelessguy2005]

I would look at the scope as a potential cause for your problems. To eliminate that possibility I would swap it for another scope that you have used and are sure of its performance. If you still experience the same problem you have ruled out the scope. Let know what you find.

[Michael]

That is why i bought the 4x16 i had a diff scope of their and did the same thing ended up maxing out? What do you suggest?

[wirelessguy2005]

if you have determined that its not the scope I would start taking some measurements on the scope rings. Its possible that the height of the rings are inconsistant and therefore throwing the scope off. If it is a problem with the rings i would replace them versus trying to shim them. I have owned many CZ 527's and i have never had to shim a set of rings. If you are looking for an alternative set of rings I would highly recommend the Leupold rings.

[Jim White]

Have you tried a box test to see if the scope tracks?

[Michael]

What is a box test? Are the leupold rings compatible with the bsa? New to this field so sorry if the questions seem dumb.

[GTOHunter]

Make sure You have the right ring in the correct spot....I have the CZ-USA 527 in the "Varmint" and we accidently put the rings in the wrong spot...took them off and noticed the back ring (I believe) had a square key-way to fit in the notched-out spot on the Rifle.It actually fit when we had the rings in the wrong spot but if You looked closely You could see that the 1 ring wasn't flush....so it could cause sight alignment if it wasn't locked down tight?




On another side note:

When I sighted my CZ .204 Rifle I got it close at 50 yards then right on dead center at 100 yards since most of my shots would be in that range...then I tried it out to 200 yards and the bullet was hitting a little high at that range so I'm thinking it was still climbing and hadn't Peaked out.....maybe You need to set it at 100 yards and then see where its hitting out at 200 yards?

[RowdyYates]

X2 on the location of the locking lug of the rear ringmount. It is possible to mount it wrong. No way should you be 4" low with those stock rings and 2 different scopes.

[Mega]

If this is the second Scope with the same problem I would be looking very closely at the mounting rings.

Either as suggested they are not attached correctly or somehow both rings are not the same height.

Something seems very wrong with the Scope Mounting.

Perhaps a visit to see someone that has a bit more experience if you are unsure...local gunshop or perhaps gunsmith for a quick look.
I feel they should be able to solve the problem in minutes.

[Michael]

I took the measurements on the rings and they back were a hair higher off than the front would that cause any of the problem I am havin?

[Michael]

I made sure the back ring was in the notch, now the measurement I took was the space left between the top part of the ring and the bottom part of the ring. When I measured, the back ring was not as tight as the front ring so their was a a noticable void space between the top and bottom of the ring. Could this be the problem?

[Mega]

If the back ring or back of the scope is higher than the front then you should be having the opposite problem...ie shooting way too high as it would elevate the muzzle in respect to where you are sighting through the scope. Back being the closest to you, furthest from the muzzle. Think I'm right....???? Bit tired after a hard day.

If it was me, I would remove everything. Take the ring mounts off, make sure they are clean, make sure the notch and the block in the back ring align and re-mount both making sure they are tight. Centre the scope carefully....ie wind the elevation to max in both directions taking note of how many clicks it takes, divide that by two and set it to middle. Mount the scope, set up a target at 50 yards. Take the bolt out, look through the bore and centre it on the target, check through the scope and it should be close or within a few inches. If all is fine fire a shot and see where it lands, then adjust the scope. Hopefully it's within a few inches.....1" @ 50 yards = double the click value per inch.... ie 1/4 MOA Click = 8 clicks to move an inch @ 50 yards.

Hopefully you can do this on a good sturdy front rest and rear bag that holds the rifle steady without moving whilst adjusting.

If the bore sighting is miles off, especially way too low as you report then I'd say you have a serious problem somewhere.

After thought....make sure the front ring mount doesn't have a recoil lug underneath....???? Whilst you have got both mounts off measure the distance from the scope base to the mount base...the flat part. They should be the same on each mount.... digital calipers.

I don't know what ammo you are using but 32gr Federals @ 4030fps should be 0.1" low at 50 yards, 0.7" high at 100 yards and Zero at 200 yards.... give or take...!!!! Factory info.