Leupold CDS problem? Base problem?

[Joe Hulburt]

Been playing around with my new .308 and CDS scope and I finally figured out last night that the reason I always hit low at 500 yards is because the scope runs out of adjustment when I get to about 4.4 on the custom dial. I had noticed the same thing with the MOA dial I just figured it was me as I have never shot that far before.

Scope tracks PERFECT at 300 yards. I see where people often need a 20 MOA slopped base to reach out to 1,000 yards but it seems odd my new Winchester would need one to reach out to 550 which is where the dial ends and is as far as I care to shoot.

Any thoughts? It looks to me like my rear base is thicker than the from base. Reverse them? Keep in mind I usually hunt with an old 30-30 or a bow and I'm very ignorant about dial scopes.

 

[MinnesotaHunter]

What type of action is it. the base for a Rem 700 is thicker at the back than the front.

When you say it runs out of adjustment do you mean it stops, or it still turns but doesn't seem to adjust any further?

 

[1_pointer]

Sounds like you had to use too much of the available adjustment to get the scope sighted in, not leaving enough to adjust for the range your shooting. What kind of bases are on the rifle? If Burris makes Signature rings for the bases buying a set would probably be the cheapest solution. They come with inserts that allow you to add slope, in any direction, to the scope. Using these, you should be able to get your scope sighted in closer to the middle of the adjustment range allowing you to use the full turn of your CDS dial.

 

[MinnesotaHunter]

there is probably something screwy with your scope or bases if you are running out of adjustment at 500. I would start with the bases.

 

[Joe Hulburt]

What type of action is it. the base for a Rem 700 is thicker at the back than the front.

When you say it runs out of adjustment do you mean it stops, or it still turns but doesn't seem to adjust any further?

It's a WInchester Model 70 and I see now that the rear base has to be thicker than the front due to the fact that the rear part of the receiver sits lower than the front. That was just wishful thinking they were reversible.

By running out of adjustment I mean the crosshair quits traveling as I turn the dial. The scope has 20 clicks left in it at that point.

 

[Joe Hulburt]

Sounds like you had to use too much of the available adjustment to get the scope sighted in, not leaving enough to adjust for the range your shooting. What kind of bases are on the rifle? If Burris makes Signature rings for the bases buying a set would probably be the cheapest solution. They come with inserts that allow you to add slope, in any direction, to the scope. Using these, you should be able to get your scope sighted in closer to the middle of the adjustment range allowing you to use the full turn of your CDS dial.

I am not sure what kind of bases they are. My buddy who sold me the rifle had them on it. I believe the rings are regular Burris. I will look into the Signature rings if I learn it is not a scope issue. Gotta call Leupold....

 

[WapitiBob]

You can look on Leupy's web site and see how much travel it will have. I don't know of any scope that keeps turning when out of adjustment, the turret will stop. You can call them too. I sent mine back for an overhaul and had it back in 2 weeks.

 

[MKotur325]

The Leupold Optics with CDS dials and 1" tubes have 52MOA on the dials. Taller rings will likely create less available travel for drop. If you are going to swap rings and possibly bases, put the lowest rings on that will support the scope bell. That may help as well.

If you want to push your .308 out 1000yds and beyond. It may not be a bad idea to look into an optic that has more travel. From a 100yd zero it takes 36MOA of travel to cover 1000yds with a 175gr SMK at 2550 at 4000'. That would only leave you 16 minutes of fudge to cover zeroing space and making sure you have enough turret travel. IMO, that's not enough.

If your turrets continue clicking after movement stops, I've seen that on several manufacturers of optics. Not previously on Leupold optics. Have you put a borescope on it to verify that the crosshairs no longer move?

 

[Joe Hulburt]

Thanks for the input guys! I learned a few things today.

First off the Tech at Leupold immediately guessed that I had to make a lot of windage adjustment when I mounted the scope and he was correct. I pulled the scope of a 7mm/08 and when I mounted it on the .308 and looked down the barrel it was way off center forcing me to make major windage adjustments. The problem with that is you loose elevation adjustment the farther you get away from the centerline of the scope which I did not know. To check this he said to place a mirror against the front end of the scope and compare the reticle to the mirror image of the reticle and sure enough I am way off center. The solution is a base with windage adjustment which should leave the scope with enough vertical travel but to be safe I am going to get the Leupold base with 15 MOA slope. That should take care of it. He offered to send me a shim for the rear base but I would rather get the scope mounted straight on the rifle. I intend to use it the rest of my life and it would always bother me knowing it wasn't just right.

MKotur325,

At this point I don't have much interest shooting beyond the 550 yards the CDS dial will give me. If I do I will take you advice and get a different scope with a standard dial. This rifle is just for hunting and I don't see myself ever trying a shot beyond 500 yards. I am just not that good of marksman. Plus I really don't want to have to convert MOA on a chart in hunting conditions. I'm too excitable for that! I like the simplicity of setting the custom dial to the yardage.

 

[1_pointer]

FWIW, the Burris Signature rings can be used to offset for windage as well. I'd do that well before going to a windage adjustable base.

Good luck! I'd be interested in hearing how you solve the problem and how your shooting at distance goes.

 

[MinnesotaHunter]

Problem solved! that is an interesting issue.

I have never used the signature rings, but I have used the Leupold Standard ring/base combo and they are super simple and solid, and the rear base allows you to adjust for windage. Depending on the rings you have, if the back base has apposing screw heads that secure the ring, you already have a windage adjustable base. I have actually seen people have issues not having enough windage adjustment, and they had actually just screwed up setting their back ring.

 

[Joe Hulburt]

Well I tried the two piece Leupold base and ring combo and it worked great for adjusting the windage but I lost ground on the verticle adjustment even with the reticle in the center of the scope. Once zeroed at 100 the dial will only turn to the 400 yard mark. I need the long range one piece base that has 15 MOA slope to get out to 550 yards. It's on order.

Hunting spring bears with the bow for a while.

 

[WapitiBob]

Sounds good. I use a 20 MOA base on my rig. Good luck with the bears.