I've got $150 to work with and would prefer metal to plastic. Short of a sale, that pretty much rules out the more-respected names. So I'm looking for recommendations.

The other question is regarding sighting-in. My upper is 10.5" 5.56 and I would like to know what y'all use for distance. I would likely not use this over 100 yards, as I have rifles. Does anybody have data on (say) a 50-yard zero and the impact difference at 25 and 100 yards?

Thanks in advance for any advice.

https://www.amazon.com/Magpul-...MAG276/dp/B00CLGLRD0

Here ya go. MBUS Pro for $154.

For ballistics I recommend the JBM site.

The critical question is what load you will be using, and especially the bullet velocity for 10.5 inches. Shortening the barrel in such lengths reduces velocity significantly. For example, the velocities I measured with Lake City M193 (55 grain FMJ) were:
16" - 3039 fps
11.5" - 2752 fps
7.5" - 2234 fps

You may be able to find data for 10.5" with an Internet search, and then it’s necessary to know the weight and ballistic coefficient of your bullet.

quote:

Originally posted by sigfreund:
For ballistics I recommend the JBM site.

The critical question is what load you will be using, and especially the bullet velocity for 10.5 inches. Shortening the barrel in such lengths reduces velocity significantly. For example, the velocities I measured with Lake City M193 (55 grain FMJ) were:
16" - 3039 fps
11.5" - 2752 fps
7.5" - 2234 fps

You may be able to find data for 10.5" with an Internet search, and then it’s necessary to know the weight and ballistic coefficient of your bullet.

Thanks, Sigfreund. The barrel is 1:7, so I got some M855, as selection here isn't plentiful. Pretty much all the searching I did brought links to "11.5" versus 10.5". I'll do some more looking and go to JBM.

quote:

Originally posted by Spiff_P239:
https://www.amazon.com/Magpul-...MAG276/dp/B00CLGLRD0

Here ya go. MBUS Pro for $154.

Nice..I didn't even know Magpul had metal sights. Found lots of stuff for more costly brands like Troy or pot metal Nc Star stuff.

Based on one source, it seems that M855 will run about 2600 fps or a bit more from a 10.5 inch barrel.

Standard atmospheric conditions and the data for the M855 bullet:
Velocity: 2600 fps
Weight: 62 grains
Ballistic Coefficient, G7: 0154
Height of sight over bore: 2.5 inches (estimated)

With a 50 yard zero this is the trajectory per JBM:

25 yards: - 1.1 inch (below line of sight)
50 yd: 0
75 yd: + 0.7 inch (above line of sight)
100 yd: + 1.1 inch
125 yd: + 1.0 inch
150 yd: + 0.5 inch
175 yd: - 0.5 inch (below line of sight)
200 yd: - 1.9 inch

I like the MBUS Pros and have them on two guns.

There will be some vets day sales coming.

Primary Arms has the metal magpul sights for 152.