[bermise]

I have the standard fixed front sight from HK on my 10.4" upper kit now and was wondering which rear sight is the proper size for my fixed front sight and 10.4" barrel.

I know there is a folding HK416 front sight in 28mm and 33mm. Not sure what size the fixed front I have is.

I was planning on using the rear sight from my MR556 but I have read it is to be used with 14.5-16.5 inch barrels. Any one running a MR556 rear sight on their 416 upper? Can it be adjusted to work properly?


Here are links to both styles of rear sights:

HK 416 rear sight, HK 416 rear diopter set. - HKPARTS.NET

HK 416 rear sight, HK 416 Diopter - HKPARTS.NET

 

[pb_removed]

Is this a joke?

The one for the 10.4" (or 10.5, or 10.3 or whatever) barrel

 

[bermise]

No, it is not a joke. Please refrain from increasing your post count.

 

[khanda]

There is a difference between the MR556A1 diopter rear sight, HK416 14.5" diopter rear sight, and the HK416 10.5" diopter rear sight. Apparently, there are a number of dots below the number '2' setting on the HK416 14.5" diopter rear sight and the HK416 10.5 diopter rear sight.

Two dots mean that it is designed for the HK416 with a 14.5" barrel. One dot means that it is designed for the HK416 with a 10.5" barrel. If you want a sight designed for the trajectory from your 10.5" barrel, I'd look long and hard for the rear sight with the one dot under the '2' designation.

This post is probably jam-packed with mistakes, so please correct me guys if I am wrong about anything in any way.

 

[Hunter Rose]

No, it is not a joke. Please refrain from increasing your post count.

Uhhh, he gave you the answer.

The one for the 10.4" (or 10.5, or 10.3 or whatever) barrel

The 10.4" diopter rear is the one you need for a 10.4" upper to have the 2, 3, and 4 settings be ballistically correct for the shorter barrel. The fixed front that comes with the MR556 is a 28mm sight line.

However, if you're like me, and don't shoot irons out to 400m, you should be able to use the MR556 rear diopter. Just pick your favorite aperture setting, zero it for 100yds or 50/200 yds (whatever your preference) and just realize you are limited to that specific aperture. If you're running a red dot or optic, the diopter is after all just a BUIS.

 

[bermise]

Uhhh, he gave you the answer.



The 10.4" diopter rear is the one you need for a 10.4" upper to have the 2, 3, and 4 settings be ballistically correct for the shorter barrel. The fixed front that comes with the MR556 is a 28mm sight line.

However, if you're like me, and don't shoot irons out to 400m, you should be able to use the MR556 rear diopter. Just pick your favorite aperture setting, zero it for 100yds or 50/200 yds (whatever your preference) and just realize you are limited to that specific aperture. If you're running a red dot or optic, the diopter is after all just a BUIS.

I do not plan to shoot the rear iron sight often, it will be a back up for an optic. If it will work as you explained that is fine with me. I really did not want to pay $190 for a rear sight if the MR556 diopter can be adjusted. Thanks for the info.

 

[pb_removed]

I do not plan to shoot the rear iron sight often, it will be a back up for an optic. If it will work as you explained that is fine with me. I really did not want to pay $190 for a rear sight if the MR556 diopter can be adjusted. Thanks for the info.

Had you posted this information, I would have answered differently. As it was, you basically asked:" I have configuration 'A', should I used rear sight for configuration 'A' or configuration 'B'?

...post count? You got a lot to learn, son.

I don't know why HK decided to get all specific on their 416 and 417 diopters (5 total by my count) when I believe the 91 and 93 use the same. I have no doubt you could use any and still be relatively effective. Heck, i've been utilizing a 91/93 rear sight drum for years on my 14.5" 416 with great success from 0-200m. But hey, $190 is a drop in the bucket for a $4k upper.

 

[Grumpy]

I don't know why HK decided to get all specific on their 416 and 417 diopters (5 total by my count) when I believe the 91 and 93 use the same. I have no doubt you could use any and still be relatively effective. Heck, i've been utilizing a 91/93 rear sight drum for years on my 14.5" 416 with great success from 0-200m. But hey, $190 is a drop in the bucket for a $4k upper.

I was wondering about this just yesterday actually.

I don't like the fact that the MR556 drum is all ring sights due to the fact that when co-witnessed with a dot optic, the top of the ring interferes with my sight picture. So I ordered a 93 drum sight with the "1" setting being the V notch in the hopes that I can switch drums and clean up my sight picture, but still retain the intended BDC of the 93's 5.56mm drum.

Other then the barrel length difference causing BDC zero's to not match exactly, how far in the ball park do you think i'll be?