SA20 optics

Longshot338

Longshot338

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Southern Ontario
Hey there,

I am getting a Colt Canada SA20 upper very soon.

I have a Hi-Lux CMR to put on it.

When I tried the CMR on my brothers 16" upper, the A-frame gas block obscured my reticle top to bottom zoomed out. Zoomed in to 4x, I could see "through" it, but it was unacceptably blurred.

I have TPS steel low rings.

How do I fix this?

Will higher rings or an AR Unimount like a Warne RAMP mount fix this? Or do I need a different fix?

I would rather not remove the A-frame gas block/front sight. I want to keep this as close to a C7 as possible.

On the other hand, my TPS rings have my optic as close as possible to the bore. This reduces parelax error, and I like the ergonomics of it.

Any suggestions?
 
Are you actually able to get your eye positioned properly with low rings on an AR? If it were my optic I would just get standard height rings or even better a one piece base.

From what I've been taught about parallax error (and I'm no expert), it pertains to the position of your eye relative to the axis of the scope not the position of the axis of the scope to the axis of the bore.
 
I have the exact same rifle and optic. Works great for me and I've never experienced that particular problem. I mounted my optic on a GG&G FLT QD base with rings from Wolverine, which are not exactly high.
 
I would suggest just going with higher rings or mount such that the front sight tower is in the lower portion of your FOV. I have the same situation with my 3x Elcan and honestly I just ignore the tower or use it as a reference for my head position behind the optic. If the tower is centered on the vertical stadia line on my scope....I am being consistent.

As for obscuring the field of view on a target...it's never been an issue for me personally.
 
Your low rings are probably designed for bolt action rifles, with the stock cheek lower than the height of the receiver.

For AR15, the standard mounting height is 1.5" and you will see a bit of a shadow at 1X. If you want it to completely clear the front sight, you can opt for 1.93", that is designed to clear laser pointers.

There are the two most common ( standard ) scope mount heights for AR.
 
I would have no problems if it were obscuring the lower portion of my field of view. However, the way it is now it obscures my entire vertical reticle from top to bottom.

Now; I was trying this on a 16" upper. Maybe on my 20" with the front sight a bit further away it will be less of an issue.

Suppose I went and bought high or extra high rings. Maybe a Unimount like a Warne RAMP mount. Do you think that will give me the height I need?

I don't mind if the A-Frame blocks the lower portion of the reticle's BDC scale. I just do t want to spend $140-$200 on new TPS rings or a unimount and find that it doesn't cut it.

Tha ks for the input so far guys!
 
Longshot338 said:
I would have no problems if it were obscuring the lower portion of my field of view. However, the way it is now it obscures my entire vertical reticle from top to bottom.

Now; I was trying this on a 16" upper. Maybe on my 20" with the front sight a bit further away it will be less of an issue.

Suppose I went and bought high or extra high rings. Maybe a Unimount like a Warne RAMP mount. Do you think that will give me the height I need?

I don't mind if the A-Frame blocks the lower portion of the reticle's BDC scale. I just do t want to spend $140-$200 on new TPS rings or a unimount and find that it doesn't cut it.

Tha ks for the input so far guys!
Click to expand...


I have no idea what a Warne RAMP mount is , or the high/extra high rings. You should figure out the actual height of the ring you are choosing. If you are looking for a low cost solution, I think Buris makes a series of mounts for AR.
 
I'm not familiar with your optic or it's mounting system, but if it's rings, then Personally I would just run taller rings. As Greentips said, Burris makes some good, cost-efficient rings. Or, just keep your SA20 running irons ;)
 
greentips said:
I have no idea what a Warne RAMP mount is , or the high/extra high rings. You should figure out the actual height of the ring you are choosing. If you are looking for a low cost solution, I think Buris makes a series of mounts for AR.
Click to expand...

I only mentioned the Warne mount because a local store has one in stock. I like the design, and a friend of mine is happy with his. I am not hung up on that brand for any reason, I would be happy with Leupold, TPS, Badger Ordnance, and the like.

I will try my friends mount out if he will let me.

As I mentioned before, maybe having that gas block 4" further from the optic will make enough of a difference with the rings I already have. Have to wait till I have my SA20 to see.

Thanks for the input guys. I have learned that it is possible to run a CMR on a SA20 and get a proper mount. I don't think I will replace the A-frame gas block. I want to be as close to a C7 as I can.
 
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