Foxtrot Mike and KAK Suppressed .45 ACP Build

Not long ago I picked up a Foxtrot Mike MIKE-45 lower for use in a 10mm build. Foxtrot Mike doesn’t really market them for 10mm but when I reached out to them they said it should work, but that they hadn’t tried it. The 10mm is another story, but once I had the lower in hand I realized that I may as well build a .45 ACP upper for it too, since that’s what it was designed to work with.

The DeLisle Connection

I’ve long been fascinated with the British WW II Delisle suppressed carbines. These were modified Lee Enfield rifles chambered in .45 ACP and fed from a 1911 magazine, and were fitted with a big integral suppressor. They were used for clandestine operations, and were used by both British and American commandos as well as the Special Operations Executive (SOE). They were apparently extremely quiet and saw use well after WW II.

While there are some companies that have done modern reproductions of the DeLisle, they’re a fairly pricey prospect. I keep holding out hope for some current company to make a bolt action suppressor-ready carbine in 9mm or .45 ACP (yes I’m talking to you Marlin) but until they do I’m on my own. Being that I had a .45 ACP lower sitting in front of me I decided that I was going to build a dedicated suppressed upper for it as my nod to a modern Delisle, albeit in semi auto form.

The Foxtrot Mike MIKE-45

Let’s talk about the Foxtrot Mike lower first since that was the starting point of my build. A buddy of mine has a 9mm Foxtrot Mike carbine that I was impressed with so, when I started looking for a lower that would take Glock 10mm mags, I looked to see what they had. Foxtrot Mike has lowers that will take either Glock 17/22 sized mags or large frame Glock 20/21 mags. It’s worth noting that they’re one of the few companies that offers a large frame Glock mag compatible lower with a bolt hold open feature that doesn’t require a proprietary upper. I already knew that the build quality on them was good, and that they had a nice set of features. After comparing them to the other options available on the market, I ending up going with a MIKE-45 complete lower half, minus a stock or brace.

Foxtrot Mike’s lowers are made from aircraft grade aluminum and finished with a matte Type III anodizing. They come with an ambidextrous safety and a Mil Spec trigger assembly with a straight blade. They feature an extra wide mag well for easy reloads. The mag release is a big, easy to use billet paddle. A steel ejector and last round bolt hold open are installed on the lower as well.

The MIKE-45 lowers are fitted with an A5 buffer tube and use an AR10 .308 recoil spring with a heavy 13.5 ounce buffer. The heavy spring and buffer are needed for proper function with the .45 ACP or 10mm loads. The MIKE-45 came fitted with a Thril Rugged Tactical AR Grip. I had never used a Thril grip, but it was solid and comfortable. The MIKE-45 complete lower half has an MSRP of $259 and is covered by a lifetime warranty. I thought that was pretty reasonable.

Since the lower was complete other than a brace or stock, I added a Magpul BSL arm brace since I was intending on building both my 10mm and .45 uppers as pistol builds. I may SBR the MIKE-45 someday, but I figured I’d start with it as a braced pistol and go from there.

Where To Buy

The KAK Upper Half

With the lower in hand and ready to go, I started looking at what I needed for my .45 upper. I already had a suppressor in hand. One of my first cans was a Huntertown Arms Guardian .45 suppressor. It was fairly inexpensive, rugged and simple. I have adapters for 9mm and .40 S&W for it as well but I don’t tend to use it a lot. It makes things hearing safe, but it’s not super quiet. Huntertown Arms has since gone out of business and I’m starting to look at newer cans with better sound suppression, so I was willing to use this one for a dedicated .45 build.

I took a look around for barrels and found a 5.25-inch model along with a .45 ACP Bolt carrier Group from KAK Industry. I use a lot of KAK parts in builds and have had good luck with them. They’re pretty affordable, too. The .45 ACP BCG was $145 and the nitride barrel was only $115. I added a KAK Big Latch charging handle to my order and called it good. The Big Latch charging handles are only $24. They’re basically a Mil-spec charging handle with, well, a big latch. They’re simple and work well. I use them on a lot of my builds.

For the upper itself I like the KM Tactical billet receivers. The have specific PCC models with an over-sized ejection port for pistol rounds. They’re clean designs with no forward assist and a small but effective brass deflector bump. Best of all they’re only $48 and they work. If you didn’t catch it by now, I’m a fan of basic budget builds, as long as they work.

When it came to handguards it was harder than I thought finding one that would fit over my Huntertown suppressor. It’s not super fat, at about 1.35 inches in diameter, but that’s still larger than most handguards inner diameters. After looking around for a while, I found that Midwest Industries makes a line of handguards specifically for use with suppressors. I found the 12.6 inch SP-Series that I needed at AIM Surplus on sale for $148.

I’m calling this the KAK upper half since the barrel and BCG are the heart of the upper, but it does have the KM Tactical upper and Midwest Industries rail as well. Assembly was pretty painless. Since it’s a blow back PCC I didn’t even have to worry about a gas block and gas tube. I torqued the barrel down using Midwest Industries provided barrel nut, threaded on my suppressor, and then installed the rail. The Guardian .45 is 9 inches long, so after threading it on the 5.25 inch barrel the overall length was right around 13 inches. That made it just barely protrude past the 12.6 inch rail.

The Total Package: The FM-KAK .45

Dropping the newly built upper on my Foxtrot Mike lower I ended up with a nice, compact package. Overall length with the brace collapsed is 28.5 inches and 31 inches with the brace fully extended. The weight is 6.15 pounds empty with the sight installed and no magazine. Not super lightweight, but not bad either. The FM-KAK hybrid was born.

I had an older Swampfox Kingslayer 1×22 reflex sight on hand to use for the build. It has a circle dot reticle with a 3 MOA center red dot. I’ve used it on pistols before, but found that the circle on that model is pretty large and works better on a long gun or PCC pistol build or on a shotgun. I put it on a new Rebel Riser from Swampfox to make for a more comfortable head position when shooting. That also raised it up high enough to use with a magnifier if I want to.

Range Time

When it came time to go to the range I rummaged around my ammo locker and came up with a variety of .45 ACP loads. I had a mix of FMJ and hollowpoints, all in 230-grain weight. I used Glock 21 factory 13-round magazines as well as KCI 26-round magazines. I will note here that Foxtrot Mike doesn’t recommend anything but Glock factory mags in their lowers. I’m not always a rules follower though, so I got some of the extended KCI mags anyway. I think Foxtrot’s theory is that the Glock factory mags have more consistent quality control than aftermarket mags and they know those will work. Aftermarket mags can vary greatly in quality so it’s hard for them to guarantee they’ll work with their lowers. The KCI Mags are built the same as Glock factory mags though with a polymer shell over a metal liner. I got four of them and they looked well made. If they weren’t marked KCI I might not have realized they were not something that Glock offered.

I sighted in using the Speer Lawman 230-grain FMJ loads. Sight in was pretty quick with the Swampfox Kingslayer. Although it’s now a legacy sight and has been replaced by newer models, it still works great. About the only criticism I have of it is that I wish it had more positive clicks for windage and elevation adjustment. There’s a little bit of guesswork involved, but nothing that really delayed sight in.

Shooting was done from a Caldwell rest at 25 yards. Grouping was the best 5-shot groups. Since all of my loads were 230-grain weight, they all hit with pretty much the same point of impact. Accuracy was consistently under 1.5 inches at 25 yards with all loads tested. Being that this was a 5.25 inch-pistol barrel I was pretty content with that.

American Eagle 230-gr. FMJ 1 1/4 inches

American Eagle Syntech 230-gr. TSJ 1 1/4 inches

Hungarian MFS 230-gr. HP 1 5/8 inches

Speer Gold Dot 230-gr. HP 1 5/8 inches

Speer Lawman 230-gr. FMJ 1 1/4 inches

The build was 100% reliable with all of the loads used. The Gold Dot and MFS hollowpoints have a pretty big cavity too but didn’t present any problems. It’s worth noting too that there were no mag related issues in the least. Both factory and KCI mags locked in perfectly and locked the bolt back when empty. Both dropped free fine as well. Foxtrot Mike may not recommend anything but Glock factory mags but the four KCI mags I had worked perfectly, which is nice, because if I have a PCC-style build I like to have extended magazines for it.

The Sounds of Silence

Since the whole point of this build was to make an ersatz integrally suppressed platform I’d be remiss if I didn’t talk about the suppressor performance. Honestly, I’d like to say it was awesome but, as my kids would say, it was “mid.” The Huntertown can brings the .45 ACP down to a hearing safe level. You can shoot without the need for plugs or muffs, which is nice. I won’t say that it’s quiet though. In real life suppressors are not movie quiet, but this one is still noticeably louder than other cans I’ve used. There’s a decent crack to it. If you only fired a couple rounds it might not be obvious that it’s a gunshot at a bit of a distance, but you definitely can hear it.

Still, being able to shoot without earplugs is a bonus, and it would make it a good candidate for a house gun. Recoil is mild as well, and there was no noticeable muzzle blast with the can installed. I didn’t have any blowback issues but my buddy, who is left handed, did notice some firing from the left shoulder. Ejection was positive and the KM Tactical upper has enough of a brass deflector bump that he didn’t get hit in the face with empty cases.

Wrap Up

Overall, I’m calling this build a success. The Foxtrot Mike lower is very well made and operated flawlessly. It’s a solid lower at a good price, and I appreciated the last round hold open feature that not all PCC’s have. The KAK barrel and bolt were great as well. Plenty accurate for what I’m doing, and zero malfunctions. They worked well with the KM Tactical PCC upper, too.

The Midwest Industries SP-Series handguard worked out perfectly. It’s a solid, well machined system with a good barrel nut provided. It has plenty of M-LOK mounting points, as well as anti rotation tabs, and it matched up with my upper fine. It came with a five-slot Picatinny rail too, which I’ll eventually drop a light on.

I’d have liked the build to be a little quieter than it is, but it still does the job adequately. It was my first suppressor and fairly inexpensive. Knowing what I do now, I’d do a little more research before I jump at a “bargain” but the Huntertown does do what it’s supposed to. It makes the round hearing safe, and it’s a pretty robust unit. I think it works out okay for this build. And now that I dedicated it to the FM-KAK, it will give me an excuse to look for a newer, quieter suppressor for my next project!

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