vertical adjustment problem
this is a Bushnell 4200 6-24 I've had for about 5 years with no problems. i've shot the same load for a long time and just tried a different powder, got excellent results but needed to raise point of impact up 3" at 100 meters. Gave it 12 clicks, fired 3 groups that continued to provide nice tight clusters but the POA did not budge at all. I've twirled the turret back and forth 360 degrees and got the POA up about 2 inches. I don't recall having so this much trouble adjusting any scope before. Any tips? Should I send it in for repairs?
30 March 2015, 11:05
sambarman338They don't always move in exact quarter minutes as claimed, but it sounds like you're saying there is no more adjustment in it.
Was the scope mounted properly in the first place? By that I mean: was it mounted more-or-less to boresight without winding the turret adjustments out of centre?
If not it may be that it was taken to the edge of the clicks in the first place rather than having the mounts shimmed or milled, leaving you with no more adjustments to use. This is a bad situation, even if you do get it to the zero you want, as it can result in distorted groups and possibly misses from poor head position.
02 April 2015, 06:59
SnellstromIf it were me I would look up their return address and ship it back to them for a going through. They have been relatively easy to deal with for me in the past. Describe the problem in simple terms and they will rebuild it free of charge or replace it with new.
04 April 2015, 07:44
StonecreekSounds like you've simply run out of adjustment -- or that your reticle adjustment is broken. It is possible that the mechanism has not been damaged by attempting to force it too far. You should be able to judge if your elevation adjustment is working properly by simply resting the rifle on sandbags and looking through the scope while turning the adjustment to see if the reticle moves on the target.
There should be a point at which you meet significant resistance when adjusting to the maximum of the adjustment range. Try going both directions until you hit this point, then crank it back to the approximate middle of the range. If your scope is then pointing significantly higher than where your barrel is pointing then you'll need to shim under the rear mount to place your zero nearer the center of the adjustment range.
04 April 2015, 18:57
JGRaiderNot sure what your mount set up is, but if you're set up to use Burris Signature rings with the poly inserts, you can buy the inserts with MOA offset that will easily solve the out of adjustment problems.
06 April 2015, 00:00
OLBIKERquote:
Originally posted by Stonecreek:
Sounds like you've simply run out of adjustment -- or that your reticle adjustment is broken. It is possible that the mechanism has not been damaged by attempting to force it too far. You should be able to judge if your elevation adjustment is working properly by simply resting the rifle on sandbags and looking through the scope while turning the adjustment to see if the reticle moves on the target.
There should be a point at which you meet significant resistance when adjusting to the maximum of the adjustment range. Try going both directions until you hit this point, then crank it back to the approximate middle of the range. If your scope is then pointing significantly higher than where your barrel is pointing then you'll need to shim under the rear mount to place your zero nearer the center of the adjustment range.
This works good only if you do it before the rings are tightened.
06 April 2015, 18:59
Andre MertensI remember having run in the same problem, decades ago. A friend revealed me a simple trick : shimming the rear base with a mating piece cut out of a coke can.

06 April 2015, 21:10
AnotherAZWriterquote:
Originally posted by Stonecreek:
Sounds like you've simply run out of adjustment -- or that your reticle adjustment is broken. It is possible that the mechanism has not been damaged by attempting to force it too far. You should be able to judge if your elevation adjustment is working properly by simply resting the rifle on sandbags and looking through the scope while turning the adjustment to see if the reticle moves on the target.
There should be a point at which you meet significant resistance when adjusting to the maximum of the adjustment range. Try going both directions until you hit this point, then crank it back to the approximate middle of the range. If your scope is then pointing significantly higher than where your barrel is pointing then you'll need to shim under the rear mount to place your zero nearer the center of the adjustment range.
If you have a boresight tool you can use this to do the check Stonecreek advises. BTW, just because the elevation knob turns doesn't mean the erector tube is moving - many scopes run out of room before the knobs stop turning.
First step is to run this test.