The HK MP5 doesn’t have much going on that could give you cause for complaint. The action is legendary and the compact footprint has proven indispensably effective in CQB encounters in the hands of law enforcement officials around the globe.
Perhaps you could bemoan the price – the HK MP5 is famously expensive – but that comes with the territory.
Truthfully, if one thing is to be lamented, it might be the nature of the rear drum sight.
Not that MP5 sights are inherently bad; in fact, they offer a clear sight picture and the rear sight offers 4 apertures to expand or home in on the target according to your preferences.
It’s just that, to adjust MP5 sights, you need a special tool. Here’s how to do it, if you’ve never tried before.
What You Need
The classic MP5 sight has a rear diopter drum with 4 peep apertures; these apertures can be adjusted without tools, and can be rotated by hand.
However, to make windage and elevation adjustments, you will need two things: a phillips head screwdriver and an MP5 sight adjustment tool. There are combination tools out there that combine both tools in one package.
Making the Adjustments
The first thing you’ll need to know about adjusting MP5 sights is that the front sight is fixed – so adjustment of the sights necessarily only entails working with the rear sight.
When you visit the range, fire a group of 3 to 5 shots at a target at the range at which you want the sights to be adjusted. Theoretically you can do this at any range you want, but since most defensive engagements occur at 7 to 10 yards, that’s a good place to start. HK recommends 25 yards; you could do that too.
Note where the shots group on the paper; they should form a nice tight group. If they don’t you need to shoot consistently until you can achieve a tight group to which you can adjust your MP5 sights.
Once you have a clear group, you need to notice whether it’s grouping right or left, and high or low. For the purpose of this hypothetical illustration, we’ll assume that your shots are grouping high and right.
If the shots are grouping high and right, what you need to do is adjust the rear MP5 sight so that it creates a radius with the front sight aligned with the point of impact. It’s also critical to note that when adjusting a rear sight, you move it in the opposite apparent direction from your group.
So, in this hypothetical instance, you need to adjust the rear sight down (elevation) and to the left (windage).
To adjust for windage, you need to loosen the set screw over the top of the rear sight. You don’t need to remove the screw; just loosen it so that the sight can be adjusted. After that, you need to loosen the screw on the sight’s right side; this is the screw that actually adjusts for windage.
HK uses an acronym, “LLC,” which stands for “low, left, clockwise.” Since our hypothetical shots grouped right, we need to turn the adjustment screw clockwise to move the sight to the left, to bring the rear sight into alignment.
At 25 yards, one full revolution of either the windage or elevation screw will produce an affected change of about 2 inches. Knowing this, you can estimate how many (or how many partial) revolutions you need to bring the sights into alignment. Since you are closer to the target, you may need more dramatic adjustments compared to if you were sighting-in at more extended ranges. You can also adjust in increments, fire a new group, and proceed by trial and error. Either way, once you have the rear sight adjusted for windage, you can retighten the set screw on the top of the sight.
That’s the relatively easy part. Now we need to break out the special sight tool to adjust for elevation so we can lower the rear sight to bring it into alignment with the group. Keep in mind that rotating the castle “turret” or diopter only changes the size of the aperture or gap in the rear sight; it does not change elevation. For that, you need the special tool mentioned.
Align your MP5 sight adjustment tool so that the two “horns” of the tool are over the detents in the top of the drum/castle sight and press it down into the sight to engage the detents. This will allow the rear sight to be rotated, allowing for adjustment to elevation.
Once again, since our hypothetical shot string trended high, we need to lower the elevation of the rear sight. Following the maxim of HK’s “LLC” mnemonic, this means we need to turn the rear sight clockwise to lower its elevation. This will lower the rear sight, bringing it closer to alignment with the shot group.
In this instance, you can once again adjust it slightly, remove the tool, and then fire a few more shots, proceeding by trial and error until you are satisfied that your sights are adjusted adequately to enable accurate shooting.
Ultimately, this is how you adjust your MP5’s sights; a little trial and error at the range, or some “guess and check” shooting will be all you need to sight in your MP5. The same basic procedure can be used with other platforms that are based on the MP5, such as our ZF-5, as well as with other MP5 lookalikes.
Here for New MP5 Sights?
If you landed here not because you need a tutorial on how to adjust the rear sight of an MP5, but because you need a replacement MP5 sight, you’re in luck.
We carry a wide range of MP5 accessories, as well as parts and other components that are compatible with the HK MP5 and MP5 clones that are popular on the market.
Take a closer look through our collection and if you need help finding anything or have questions about compatibility, get in touch with us and we will be more than happy to help.