Sniper & Sharpshooter Forums banner

1 - 12 of 12 Posts

·
Registered
Joined
·
48 Posts
Discussion Starter #1
Will a 15moa base affect my ability to attain a 100yd zero on a Rem 700 LH VS (308) w/ a vari-x III 3.5X10 tactical?
I shoot matches that sometimes require a 100yd shot, and this might affect my decision to mount the base.

Any comments, suggestions?
 

·
Registered
Joined
·
50 Posts
I have the same scope on my 10fp-le2. It has 51" of adjustment @ 100 yds. I have a 0 moa base. First group with scope at factory 0 settings was 12" low. A 15 moa base would have put me 3" high. Both are within the adjustment range of the scope, with plenty of elevation left for that 1000 yd shot.
The 15 moa base might be more preferable because you will stay closer to the scope factory zero.
 

·
Premium Member
Joined
·
9,894 Posts
Scharfschütze said:
I have the same scope on my 10fp-le2. It has 51" of adjustment @ 100 yds. I have a 0 moa base. First group with scope at factory 0 settings was 12" low. A 15 moa base would have put me 3" high. Both are within the adjustment range of the scope, with plenty of elevation left for that 1000 yd shot.
The 15 moa base might be more preferable because you will stay closer to the scope factory zero.
When all is said and done, you need about 45 MOA to shoot at 1000 with the .308. If the scope starts with 51", then you only have 25.5" of up from the true zero of the scope. And as is mentioned above, the scope's true zero may require a lot of adjustments in either up or down. (due to manufacturing tolerances on the rifle and bases/rings). Some scopes (because of these variables) "may" not have enough MOA to zero at 100 with a 20 MOA (and sometimes 15 MOA) bases.

MEL
 

·
Registered
Joined
·
50 Posts
Thanx for clearing that up Mel, I read the ballistics chart wrong :oops: . I thought it sounded kinda off. So with my 0 base, I can only zero out to 300 yds. :(
In theory, if you have a 20 moa base, and at least 40" of adjustment, you should be able to zero at 100 yds. Is that right?
 

·
Premium Member
Joined
·
9,894 Posts
If you only have 40" total, and you dial in an immediate 20 MOA of down to compensate for the 20 MOA base, then you are out of adjustments and you will probably not be able to zero at 100y. You "might" be able to, but you'll be going off of luck on that. You will usually be dialing in +-10 MOA in any direction just to zero at 100y.

For example, lets say it happens to be you have to dial in like 5 MOA of down to zero, and then add in another 20 for the base, but you only had 20 (half of 40) then you will not be able to zero at 100y.

MEL
 

·
Registered
Joined
·
48 Posts
Discussion Starter #7
Well, I'll have to hope for the luck aspect of it all. My rings should be in next week, so when the weather breaks a bit, I'll see how it goes.

Anyone know if a bore sighter has the ability to tell me anything before I hit the range?

Bigohio
'
 

·
Registered
Joined
·
50 Posts
Thanx for info Mel, I get it. I've already used up 12" of my 25.5", so best i can hope for is 13.5" high @ 100yds, that would zero me at about 450yds or so.
Well, I can see a 20 moa base is on my list off things to do now. That shoud be enough for 800 yds, I can swag the rest. Fire season is over now, and they put the steel plates back out to 1000 yds :lol:
I think bigohio should be ok with a 15 moa. But it looks like you never really now til you get it together and check. Next time i'm out I will have to check the upper and lower extremes of my elevation.
 

·
Registered
Joined
·
109 Posts
Am I the only one bothered by the fact that the Farrell 20-minute rails are a lot higher (taller) than the competition?

I'll stick with Badger.
 

·
Premium Member
Joined
·
9,894 Posts
The total height of a scope is a constant concern for me. Perhaps people with "taller" faces than I do not have this issue, but I cannot get a good cheek weld on scopes mounted high. This is one of the reason why I prefer 40mm bells over all other sizes. The 56mm objectives that are so popular now just are not feasible to me, and boy, some of the USO scopes that have 80mm + objectives, that a bit over the top.

The 20moa cants themselves raise the rear of the scope and contribute to the problem of having to raise your eye too far from the butt stock. If I need some extra MOA for a scope, I try to get the minimum possible, 15 moa or even 10 moa is more desirable than 20, but sometimes you don't have a choice.

MEL
 

·
Registered
Joined
·
109 Posts
The 20 minute taper aside, Farrell seems to make his bases (taller) thicker than most other makers for some reason.

On my favorite rig, I have enough come-ups to reach 900 yards with a flat base. If you like low, with a Loopy 3.5-10x40 the bolt handle won't even clear Butler Creek flip-up caps! I have to use a bikini-type cover, but I like it loooww too.
 
1 - 12 of 12 Posts
Top