I find with the standard A2 sights on my issued M16, it is of course very easy to quickly pick up the front sight.  How is accuracy affected by using the large aperture, within 50 yards or so?  I know it's designed for low light shooting, but since I am not issued optics, I'd like to leave the large aperture up for when I am carrying the weapon on duty.

Any thoughts?  I'm not able to hit up a range until at least next weekend, so I can't really shoot and find out myself right now.

The large aperture is for 0-300 meters and the small aperture is for 300+ meters.

Quoted: The large aperture is for 0-300 meters and the small aperture is for 300+ meters.

+1. You're doing it the right way.

When switching from the small aperture to the large aperture ( A2 sights), there is a shift in the POI.  According to LTC Chuck Santose (improved battle sight method), that shift should  be two clicks of the rear sight.  So when you shift to the large aperture, you would need to raise the rear sight by two clicks to maintain the same POI.  He points out, however, that there seems to be some variation on the amount of shift depending upon the manufacturer.

According to this web site, there are at least three variations.  

So I guess the best answer is just to get to the range, and see how much (if any) difference there is on your particular rifle when changing from one aperture to the other.

i prefer the large aperture 90% of the time, at 100yrds my groups are slightly bigger than small aperture but i can aquire and enguage much faster. but mine shifts to the side more than verticaly? i think its from the threads, as it rotates on threaded screw when fliped its like turning the windage a click or to, witch i do to compensate, but at less than a 300 meters its not going to cause a miss on man size target.

funny, i use the small sight even during our "field fire" 300 meters is the longest we shoot and move up from there. if your nose is on the charging handle, the peep is "open" enough to see around quite a bit. if it's not enough, keep your weak eye open and train your eyes to concentrate on the FSP.

needless to say, my big peep has never been used by me hug.gif

They should have tought you that in Basic.  The large aperture is also for when you're wearing your M42 (or whatever you use) Protective Masks.

Quoted: They should have tought you that in Basic.  The large aperture is also for when you're wearing your M42 (or whatever you use) Protective Masks.

I went through Basic at Ft Sill in 1998, and we were taught to always use the small aperture during qualification, and that the large aperture is only for low light shooting.  I guess I was misinformed of the true purpose.

Quoted: i think its from the threads, as it rotates on threaded screw when fliped its like turning the windage a click or to, witch i do to compensate, but at less than a 300 meters its not going to cause a miss on man size target.

Take a look at your large peep. You'll notice it is slightly off center towards the right to compansate for the threads.  It's real subtle but if you look long enough you'll see it.

boom,  that would make sense, any idea why my group shifts to the side a little? i guess i'm just trying to blame it on somthing other than me. lol . they are still good groups just over a little?