F T/R Competition 20 MOA base and scope adjustment ?'s

[Coyotejunki]

I am putting together a 308 Win for my entry into F/TR. After installing my scope and trying to bore sight it, I bottomed out the elevation adjustment and when I shot at 100 Yds I am still about 8" high, above the POA. Is this normal. I'm thinking I may put a zero MOA base on it for finding a load it likes, and then shoot it out to 600. Is the 20 MOA base mostly for 1K shooting?

 

[littlerascal56]

Re: 20 MOA base and scope adjustment ?'s

If you are running a Burris scope...some models don't have more that 30 MOA elevation built in. A 20 MOA base will do what you describe.

You probably will be better off with a 0 MOA with your setup. You still might make 1000 yards if your scope has 40 MOA (or more) elevation.

 

[jamesZ71]

Re: 20 MOA base and scope adjustment ?'s

You may want to try a 10moa base

 

[Coyotejunki]

Re: 20 MOA base and scope adjustment ?'s

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: jamesz71</div><div class="ubbcode-body">You may want to try a 10moa base </div></div>

Duh, Why couldn't I think of that. OK a 0 and a 10.

Thanks,

actually it's a B&L 8-24x 42 I think, but it has been tracking pretty good on my 243 for what little I have used it.

 

[asbestosglove]

Re: 20 MOA base and scope adjustment ?'s

An 8" high group is still a group, just not on the poa. Unless it bothers you, why change it?

 

[Bill Larson]

Re: 20 MOA base and scope adjustment ?'s

find accuarcy load at 300 yds. if possible.check loads with chrono.NEVER BOTTOM OUT SCOPE OR TOP OUT.... use larger paper with scope @ mid-adj.or normal target with aim point below it.
bill larson

 

[Trevor]

Re: 20 MOA base and scope adjustment ?'s

F Class comp start at 300yards 8" high would be approx 2.75moa most people need 4moa to get sighted in at 300. unless you want to be able to shoot at 100 or don't have a 300 yard range to practice. I think you would be ok as is.

Trevor

 

[Greg Langelius *]

Re: 20 MOA base and scope adjustment ?'s

Put a 1/2" dot at the bottom of a sheet of legal paper, and shoot it at 100yd. That will provide adequate 100yd load development data.

Then look for Burris Signature Zee rings, with switchable offset ring inserts. This gives you up to 30MOA of additional adjustability (some of which <span style="font-style: italic">could</span> be used to center the windage if that's needed.

This will allow you to tune your mounts for varying distances.

The above advice suggesting refining the accuracy load at 300yd is wise. When refining my loads at distances beyond 100yd, I tend to pay most attention to vertical dispersion. Because it is more difficult to isolate wind dispersion from natural group width at additional range, horizontal dispersion is less helpful.

If you are shooting with a scope that is limited to 30MOA of elevation adjustment, understand that the differences in zeros between 100yd and 1000yd can be more than that depending on your chambering and loads. Ths is where the offset inserts become more useful.

Greg

 

[9H_Cracka]

Re: 20 MOA base and scope adjustment ?'s

Keep the base you have, put a Brownell's brass shim under the front of the base at the screws, and keep your 20 MOA base. Once you rebarrel with a quality barrel done by a competent smith (assuming stock Remmy barrel right now) the rifle will most likely not have that same POI issue you have now.

 

[Coyotejunki]

Re: 20 MOA base and scope adjustment ?'s

Thanks for all the helpful advice. Unfortunately most of my shooting is limited to a 100 yard range. It's about a 2 hour drive to a 300 yarder, though I may join St. Louis BR club and get to shoot a bit of distance.

 

[Trevor]

Re: 20 MOA base and scope adjustment ?'s

if you are going to shim the front. take a coke can and cut a couple of shims. If you have a 1" micrometer you can measure the thckness and adjust accordingly. i believe weaver's website has the thickness as well.

Trevor