- Location
- Arnprior Ontario
I am installing a Vortex Sparc II on a S&W M&P-15 II and the mounting can accommodate absolute or lower 1/3 co-witness heights, what are the benefits of either ?
Thanks
Thanks
Installing a Sparc II, what's better, absolute or lower 1/3 co-witness heights
- Thread starter Brewster20
- Start date
Frankly the pluses and minuses don't matter. Mount the optic with one close your eyes shoulder the gun open your eyes. Repeat with the other mount. Which one lined up better without moving your head?
In my opinion the rest doesn't matter.
juancarlos
CGN frequent flyer
- Location
- The Island
If you have a fixed front sight lower 1/3 is usually preferred. If you have a front folding sight it's more personal preference. I have run both with folding sights and not really noticed a difference, not like you will with a fixed front.
Greenhorse six
CGN Ultra frequent flyer
Benefit of the lower 1/3 , your head is not bent forward , and you can run the stock shorter .
For the absolute , your irons and your red dot line up , if one is zeroed then the other can be easier to dial in [ I've never had issue with a FSB being a problem co witnessed with a red dot ] .
Something else to think about , the sights on a AR are already high over the bore axis , with the lower 1/3 you're raising them , albeit marginally , higher above the bore .
YMMV.
For the absolute , your irons and your red dot line up , if one is zeroed then the other can be easier to dial in [ I've never had issue with a FSB being a problem co witnessed with a red dot ] .
Something else to think about , the sights on a AR are already high over the bore axis , with the lower 1/3 you're raising them , albeit marginally , higher above the bore .
YMMV.
It is going to come down to preference. I have had them absolute cowitnessed and then 1/3, etc and now I have a couple mounted with no witness and it is kind of nice not to have the clutter in the optic. It comes to preference.
