All Hail the MP5
Bottom line up front: the MP5 platform was the number one choice for law enforcement and special operators worldwide in the ’80s, ’90s (and still some units today), because it is accurate, reliable, and so soft-shooting that it makes even fully automatic fire controllable. Like the AR-15, the MP5 design has evolved to become incredibly modular, so you can easily and quickly kit out the gun for whatever the mission requires.
Shooting this in real life is exactly what I hoped. It’s crazy accurate and just a joy to shoot. It barely moves, and it’s a dream to shoot fast. You just want to keep pulling the trigger. This K version is so compact that you can realistically stow it in any bag, and there is truly nothing like doing the “HK slap.”
I’m going to be talking about the MP5 in general, but I’ll be using an SP5K as an example. The K is just a few inches shorter and lighter than the full-sized MP5, with a 9-inch barrel. It works and acts almost exactly the same. The K version is just a little more compact for when you need a smaller overall footprint.
I’m also going to use the terms MP5 and SP5 interchangeably, because in common usage, they are in essence the same firearm – the MP5 is just the fully automatic submachine gun version made for military use. The SP5 and the SP5K-PDW were released to the U.S. market in 2019. There were some earlier versions, but 2019 is when MP5 variants became widely available. The SP5K is a copy of the MP5K, which debuted in 1975 as a short version of the MP5.
Unique Action
The heart of the MP5 is the roller-delayed blowback mechanism, which gives the platform its accuracy, reliability, and most importantly, soft-shooting reputation. Much has been written about this action, so I won’t bore you with all the details.
Long story short, precisely machined rollers are integrated in the bolt. Defeating the friction of these rollers delays the unlocking of the bolt after a round is fired for just long enough to keep the firearm safe.
The fixed barrel and simple design make it precise and reliable. The ingenious rolls allow the action to remain lightweight to reduce felt recoil. The other added benefit is that it produces a very easily controlled full-auto, fire which is why the special units liked it.
For the semi-auto version, this means that it is one of the softest-shooting pistol caliber carbines on the market. The SIG MPX is the only PCC I’ve shot that would give it a run for its money.
Features
Starting from the front, the SP5K-PDW comes with a 1/2x28 TPI threaded muzzle for suppressors. It also has a tri-lug adapter, which is traditionally how MP5s attached suppressors. Then we come to a shrouded front sight post and quick-detach handguard with integrated hand stop.
Next is the iconic charging handle that can be locked back by simply rotating it up into a notch. This allows the gun to be charged with the iconic HK slap – this move really is satisfying, and I haven’t found anyone who doesn’t immediately love it.
Moving back along the top cover, there are tabs designed for attaching sighting accessories. Nowadays, most people install a claw mount. The rear sight departs a little from the classic MP5 enclosed peep drum sight, using an open-top castle drum sight instead. Because the SP5K is sold as a pistol, it’s easier to sight through a notch-and-post-type sight when shooting it as an unbraced pistol.
Because it’s sold as a pistol, it comes with a simple back plate with just a sling attachment point. Don’t underestimate the fact it doesn’t come with a pistol brace, as there are uses for a naked back plate. A single-point bungee sling is included so you can shoot it braced off the sling. This small configuration would be great for under a jacket or in a bag. Also, law enforcement use this setup when they need to shoot with gas masks, because masks can impede the use of a stock or brace.
Trigger Housing
The lower grip and trigger pack is all one unit. This is where the K version differs from the full-sized SP5. The K version has two takedown butt plate pins at the rear, while the full-sized has only one. That’s why there are different stocks and braces for each platform. It’s annoying they don’t take the same accessories, but HK did this to make the K version as short as possible.
The trigger itself is okay, but it’s not match-grade. It’s a duty trigger that’s a little heavy and a little spongy. It is very usable and shootable. It’s not bad by any stretch, and I can still get great groups at 25 yards.
Magazines
The SP5K takes standard MP5 magazines. It comes with two German-made 30-rounders, which I’ve linked together with a red coupler (like in “Die Hard 2”).
The magazine button and paddle mechanisms of this SP5K-PDW are probably the most appreciated reproductions of the MP5K. The classic military MP5K had both, but earlier versions of the civilian models didn’t have the paddle release and only had the right-side button. This makes a difference because of the unique reloading procedure of the MP5.
