15,500 Rounds Later with My Century Arms AP5
If you found this page from one of our YouTube videos, welcome! Below is the complete breakdown of my Century Arms/MKE AP5, including my current setup and my experience after approximately 15,500 rounds over four years.
My AP5 was my entrance into the MP5 platform. I immediately fell in love with the design, despite having some of the most frustrating early reliability problems I’ve ever experienced with a firearm.
Here’s what happened with mine, what changed along the way, and why I chose each component currently on the gun. This is the story of my particular AP5, including the parts that didn’t go smoothly.
I’ll continue updating this page as the setup evolves, with additional observations and gear links as they become available.
Disclosure: Some links on this page may be affiliate links. If you purchase through them, Armed Appalachia may earn a small commission at no additional cost to you. We only recommend products we use, trust, and believe are worth your hard-earned money.
A Rough Introduction to the MP5 Platform
I loved the AP5 almost immediately. Getting it to work properly took considerably longer.
For roughly the first 1,500 rounds, I couldn’t get through a full magazine without a malfunction. I installed a German HK extractor, extractor spring, ejector lever, ejector spring, and even a new bolt head. It still never worked properly.
To be clear, I never reached out to the manufacturer for assistance. I wanted to figure it out on my own.
One thing I kept noticing was that the ejection was never consistent. Eventually, I began to suspect a weak recoil spring. I bought a German HK recoil spring assembly from HK Parts and ran several magazines with various ammunition brands and bullet weights.
Not a single malfunction.
After everything I had already tried, that was a welcome change. The gun began working fine for a while.
More Changes, More Fitment Issues
Fast-forward to installing the Dogwood Armory Super Safety setup, and I started having problems again.
I found a tiny bit of play in the Lee Sporting lower that I traced to the ejection trouble. I addressed the gap with a 3D-printed shim.
I also ran into a separate problem with poor stock fitment. Returning to the SB Tactical brace corrected that. It fits perfectly.
With those issues addressed, I’ve now fired approximately 450–500 rounds since the last malfunction. That’s where the current setup stands.
My AP5 Setup
Here’s what’s on mine and why I chose it.
Muzzle Brake
SPT HuDu
I already had this lying around and needed something that would extend past the handguard. What I didn’t think about was the fact that it would cook my flashlight.
More on that below.
No link — no longer available.
Handguard
UTG Pro Monolithic M-LOK Extended Handguard
It looks so cool. This is exactly what I think a modern MP5 should look like.
The gaps around the charging handle provide enough clearance that I’m not scraping my knuckles when I lock the bolt back. I also haven’t had it come loose once while shooting with the Super Safety setup. It stays put, and it stays zeroed.
Red Dot
Primary Arms MD-25 ACSS-CQB
I love these. I own two, and neither has given me a problem.
The reticle is amazing, and they have a night-vision mode. The MD-25 is 25mm instead of 20mm like an Aimpoint T2, and I prefer the larger field of view. I also like the large reticle when using the Super Safety because it helps me keep my aim centered on the target.
Riser
Vortex Crossfire II Mount
The Vortex Crossfire II is an okay red dot, but I don’t like its dial at all. I do love the mount, so I took that and mounted my beloved MD-25 on it.
It works perfectly for this setup because I can still use the iron sights by looking underneath it.
No link — this was a spare part from a Vortex Crossfire II, and it isn’t sold separately.
Flashlight
Nightstick TWM-30
I’ve owned a few Nightsticks, and I think they definitely meet Streamlight quality.
I had a Nightstick Fortem on my fire helmet that got cooked and still turns on to this day. I also have two TWM-30s that haven’t given me any issues, including the one I managed to cook on this gun.
I had it mounted directly above the muzzle brake like an idiot, and it incinerated the lens. I scraped it all off, and it looked good as new.
Nightstick lists the standard TWM 30 at 1,200 lumens and 10,000 candela.
Foregrip
DFCO Tiger Claw
This is a great grip. It makes C-clamping easier and provides a firm surface to brace my hand against.
It also has a really nice finger groove that lets me settle my support hand into the same position every time.
Pistol Grip
DFCO Kung Fu Grip
The steeper angle feels especially good to me on this compact setup. With a shorter length of pull, my hand naturally falls at an angle that matches the Kung Fu Grip, so it fills that space perfectly.
I also really like the finger groove beneath the trigger guard for holding the gun up one-handed.
Lower
Lee Sporting LS5
The LS5 is the housing I’m using with my Dogwood Armory Super Safety setup.
Mine needed a shim at the front to eliminate the play. After addressing that, it has been a breeze.
Super Safety
Dogwood Armory
This was my first experience with a Super Safety setup on the MP5 platform, and it has been my favorite upgrade to the AP5 so far.
I installed the components into the LS5 lower. The package also included a slip trip and a plastic buffer that wraps around the recoil spring.
Brace
SB Tactical SBT-5
I had a stock on the gun but ended up returning to the brace because of end-cap fitment. The lower had too much play, which was throwing off the ejection.
The SB Tactical brace fits perfectly. Surprisingly, I also find it more comfortable than most of the stocks I’ve tried.
Magazines
MAC 5 / MAC 5K Magazines
These have been good all-around magazines with adequate spring tension.
Magazine Springs
German HK Magazine Springs
I use German HK springs as replacements in my magazines. When considering a spring replacement, I also look at the condition of the magazine body and follower.
A replacement spring doesn’t turn another manufacturer’s magazine into an HK magazine, and a worn spring isn’t the only possible cause of a feeding problem.
Internal Components
The changes inside this gun have been a big part of its story. These are the components worth calling out beyond the accessories you can see from the outside.
Recoil Spring Assembly
German HK Recoil Spring Assembly
My original ejection pattern was all over the place. The German HK recoil spring assembly cleaned that up significantly and fixed the majority of my original problems.
After all the other parts I had already replaced, this was the change that finally made a noticeable difference.
Locking Piece
MAC Locking Piece
The shoulders on my original locking piece appeared worn after use. I installed a MAC locking piece, which brought my bolt gap from 0.011 inches to 0.017 inches.
I suggest researching the different functions of each type of MP5 locking piece before changing yours.
No link — not sold as a standalone part yet.
Extractor Spring
HK Rifle Extractor Spring
I prefer the HK rifle extractor spring for this setup. It’s the one I’ve chosen to use in my AP5.
What I Use for Lubrication
Firearm Frosting
After installing the Super Safety setup, I realized more than ever how necessary lubrication is for proper function.
I use Firearm Frosting because they offer different lubricant viscosities for different components. Their Blueberry Barrier is basically grease. I apply it to the slip trip and the rails the bolt rides on inside the receiver—essentially anywhere with heavy metal-on-metal contact.
I use their green bottle on the rest of the internals because it sticks around longer.
I also really like their Frosted Tips. The different tips make it easy to get lubricant into the tight nooks and crannies that are otherwise a pain to reach.
What I Use for Cleaning
Desert Tactical SC-14 Gun Cleaner
My AP5 gets super dirty, especially around the bolt head and chamber.
I’ve found SC-14 to be the best solvent for removing carbon and other fouling from those areas. It also acts as a degreaser, which is helpful when I’m dealing with excess grease and carbon in an extremely dirty gun.
Where It Stands Today
The total round count is approximately 15,500 over four years. Since the last malfunction, I’ve fired another 450–500 rounds without an issue in the current configuration.
That’s encouraging, especially after the start I had with this gun. It’s also the number I can give you today. I’ll keep updating this page as I put more rounds through it.
Final Thoughts
I love the MP5 design, and I’m happy with how this AP5 looks and feels now. The handguard gives it exactly the modern look I wanted, the MD-25 is an optic I keep coming back to, and the brace ended up being more comfortable than I expected.
Getting here took more work than I wanted. That’s part of owning this particular gun, and it belongs in the review alongside everything I like about it.
If you have questions about the gun or anything on it, send us an email or leave a comment. Thanks for sitting on The Front Porch with us.
What’s Next?
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