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View Full Version : Vortex Crossfire Scout elevation bottomed out, still 6 MOA high.



bellavite1
10-28-2016, 13:36
Well, help me out guys:

Rifle: SA M1A Socom II
Rings : Weaver Tactical High
Load: 40 gr of IMR 3031
Velocity: approx 2540 fps
Bullet: 30 cal BT 150 gr (WIDENER)

I shot the rifle both at 25 yds and 100 yds, it consistently grouped abou 6 MOA high.

Elevation on the scope is bottomed out, I called Vortex and they were no help, even though it seems to be a recurring issue with this scope.

What I am trying to figure out is this: if I am correct, a 308 zeroed at 25 yds will approximately meet a second zero at 200 yds.

With my POI being 1.5" high at 25 yds, at what distance will my actual second zero be? (approx, of course)?

My ballistic app is not helping...

I am debating whether returning this scope, all Vortex could say is that I need a scope with more travel...

Delfuego
10-28-2016, 14:58
I ran some numbers through a ballistic app and it leads me to believe your zeroed around 330-350 yards. This could be in part due to your height over bore (ring height) among other things. If your scope is truly bottomed out the only solution with that scope would be to remove elevation in your rings or scope mount. Burris signature zee rings are a way to do this. The signature rings have insert in them that can be swapped out to add/remove up to 20MOA. You would actually be going in the opposite direction as most.

Not to sound like a dick, but... If this is the Vortex Crossfire Scout scope I looked up; it retails for around $150 or so and has a duplex reticle. I am not sure what you were expecting a $150 scope. That is low-end even when compared to low-end scopes. I dont know how you were even able to calculate 6moa with only a duplex reticle to measure with. You own a $1500 M1A, you cannot expect a $150 scope to do it any favors. I would seriously reconsider your choice of optic. Even if you could get it to land where you want, it still would not help what is potentially a pretty darn accurate rifle. I dont want to come off as a snob, I just dont think it is a good investment of time and money to chase. Take a look at the SWFA 3-15x. it is very capable and not super expensive for a good rifle scope, all thing considered.

bellavite1
10-28-2016, 16:50
I ran some numbers through a ballistic app and it leads me to believe your zeroed around 330-350 yards. This could be in part due to your height over bore (ring height) among other things. If your scope is truly bottomed out the only solution with that scope would be to remove elevation in your rings or scope mount. Burris signature zee rings are a way to do this. The signature rings have insert in them that can be swapped out to add/remove up to 20MOA. You would actually be going in the opposite direction as most.

Not to sound like a dick, but... If this is the Vortex Crossfire Scout scope I looked up; it retails for around $150 or so and has a duplex reticle. I am not sure what you were expecting a $150 scope. That is low-end even when compared to low-end scopes. I dont know how you were even able to calculate 6moa with only a duplex reticle to measure with. You own a $1500 M1A, you cannot expect a $150 scope to do it any favors. I would seriously reconsider your choice of optic. Even if you could get it to land where you want, it still would not help what is potentially a pretty darn accurate rifle. I dont want to come off as a snob, I just dont think it is a good investment of time and money to chase. Take a look at the SWFA 3-15x. it is very capable and not super expensive for a good rifle scope, all thing considered.

First and foremost, thank you for taking the time to do some calculations, exactly what I was looking for.
To answer your questions:
Yes, you are looking at the correct scope, I have had great luck with Vortex so far, so, after trying a few other scout scopes, I figured I would give it a try, since, you know, it IS a $150 scope...
I believe in the right tool for the job, and a Socom II (16" barrel, non-extended cluster rail version of an M1A) is hardly a precision rifle, so I don't intend it to be.
I have the precision rifle part already covered with other firearms.
In fact, it is more of a Scout rifle, snap shot kind of weapon, in my humble opinion.
The point here being not the size of the group, but rather to fully understand the capabilities of this tool (what kind of holdover, if any, to use at various distances).
As far as calculating 6 MOAs, well, that's what a 1" grid target is for:
1,5" high at 25 yds is equivalent to 6 MOA (6" at 100 yds).
You know, angular deviation...
Anyways, I do agree with you, this scope is definitely not what I need: given the intended use of the weapon a red dot, or just even irons, will probably work better.
Thank you for your time.

Delfuego
10-28-2016, 18:59
I would check out a 1-6x or 1-8x scope. They have come down a lot in price. The vortex strike eagle comes to mind.
Maybe this one :)
https://www.ar-15.co/threads/159194-Bushnel-AR-optics-scope-w-mount
Also see what it will do at 100y, might not really be 6 moa high.

KS63
10-28-2016, 19:53
If you want quick target acquisition and be able to make hits out to 600yds, a 1-4x or, better yet, a 1-6x is probably a better choice. Like Delfuego said, look at the Strike Eagle for a solid value 1-6x.

bellavite1
10-29-2016, 07:08
If you want quick target acquisition and be able to make hits out to 600yds, a 1-4x or, better yet, a 1-6x is probably a better choice. Like Delfuego said, look at the Strike Eagle for a solid value 1-6x.
Not enough eye relief...I have the SE on another rifle.

KS63
10-29-2016, 08:23
Razor HD Gen II had 1/2" more eye relief. Seen some used ones go for a tick over $1K.

C Ward
10-29-2016, 09:51
It's mounted as a scout scope , IE in front of the receiver on the barrel . A standard scope is not going to work because the eye relief needs to be about triple of normal .

Is the mount on the rifle attached to the stock or the receiver / barrel ? If the mount is on the stock or the barrel shroud that is probably the issue because of it not being in the same line as the bore .

Everybody I know that has played with the scout rifle concept has never used more than 1.5 - 2 magnification and decided that a red dot was better suited for the job or went back to a conventional mounted variable 1-4 or similar .