New Posts New Posts RSS Feed - 20 MOA base and interal adjustments
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Check GunBroker.com for SWFA's No Reserve and No Minimum bid firearm auctions.

20 MOA base and interal adjustments

 Post Reply Post Reply   Topic Search Topic Search  Topic Options Topic Options
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/13/2014 at 10:39
adillemu View Drop Down
Optics GrassHopper
Optics GrassHopper


Joined: November/13/2014
Location: Mesa, AZ
Status: Offline
Points: 3

I have a head scratcher here, hoping someone may be able to shed light on. I have a custom Rem 700 with a 6-24 Vortex Viper PST. The rifle shoots well (sub 1/2 MOA), scope tracks well and is very repeatable. The scope has and advertised 65 MOA of internal vertical adjustment. What I found this last weekend while shooting out to 1100 meters, was even with my 20 MOA base installed, I only have 30 MOA of vertical adjustment in the scope with a 100 yd zero. I's also add my windage adjustment & range of travel is as close to centered as I could expect it to be, within 2-3 MOA.


So essentially, my 20 MOA base put me back into the middle of my range of vertical adjustment in the scope, give or take a couple MOA. I understand all rifles and installations are a bit different. I was told by Vortex Tech Support that is why they make 20, 30 & 40 MOA bases. Is it just me or is this excessive?


Much thanks in advance.


Alan



Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/13/2014 at 11:48
SVT_Tactical View Drop Down
Optics Retard
Optics Retard
Avatar
Chief Sackscratch

Joined: December/17/2009
Location: NorthCackalacky
Status: Offline
Points: 28753
In a perfect world when zero'ed at your ideal range you'd be dead in the middle of your scopes travel range in your case 65/2 = about 32.5 up and 32.5 down.   But more often than not its not the case. If you go to much of a cant on the base, 30 or 40 MOA you may not be able to zero at 100 because your bottomed out and no more adjustment.  Its a delicate balance when you have a scope with limited range.  You are not alone in your situation, happens to plenty of folks.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/13/2014 at 12:31
adillemu View Drop Down
Optics GrassHopper
Optics GrassHopper


Joined: November/13/2014
Location: Mesa, AZ
Status: Offline
Points: 3

I got off the phone with an R & D guy at Vortex a few minutes ago. He shed some more light on the situation. He says this is quite common, they see it a lot. The rear pedestal on Remington 700 actions are hand finished during the manufacturing process. It's not uncommon to have significant material removed and variations from one rifle to the next. More material removed raises line of sight, drops point impact.

Looks like I will be bedding my base and re-lapping rings.

Thanks again for the input.

Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/13/2014 at 12:39
cheaptrick View Drop Down
MODERATOR
MODERATOR
Avatar

Joined: September/27/2004
Location: South Carolina
Status: Offline
Points: 20468
Welcome to Optics Talk, Alan.  
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/13/2014 at 17:10
koshkin View Drop Down
MODERATOR
MODERATOR
Avatar
Dark Lord of Optics

Joined: June/15/2004
Location: United States
Status: Offline
Points: 10961
Many mass produced actions have significant variations in how the top of the receiver is finished.  I would not necessarily re-lap the rings right off hand.

You can add a shim between the base and the rear receiver ring and bed the whole thing.  Make sure you do not bend the base in the process.

ILya
 Post Reply Post Reply
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Similar Threads: "20 MOA base and interal adjustments"
Subject Author Forum Replies Last Post
40 MOA base with SS 5-20 TeeRex Rings and bases 14
Questions about 20 moa scope base. Bigdave Rifle Scopes 14
Vortex Viper PST + EGW 20 moa base and burris XTR matt_3479 Tactical Scopes 3
Help with selecting 20 MOA base TD Rings and bases 21
20 MOA Warne base Rattlesnakemp Rings and bases 2
20 moa base mburch64 Rings and bases 4
Elite 4200 6-24x50 with 20 moa base question BobC Rifle Scopes 1
20 MOA base for .22-250? Michael Riley Rings and bases 1
Question about one piece 20 moa bases BobC Rings and bases 5
20 moa base question jagdkampf Rings and bases 3 2/27/2006 12:33:40 PM


This page was generated in 0.344 seconds.