$899 Folding Side Charger – Foxtrot Mike FM-15: Full Review

9 Folding Side Charger - Foxtrot Mike FM-15: Full Review

Competing in an already saturated market, Foxtrot Mike Products recently released its spin on what a modern AR platform should be with the FM-15. Featuring a direct impingement side-charging assembly, the FM-15 requires no buffer tube to operate and can be fired while folded. While I tested the complete 16″ rifle chambered in 223 Wylde, the upper will fit all standard AR lowers.

9 Folding Side Charger - Foxtrot Mike FM-15: Full Review

Unique to the FM-15 is a lightweight bolt carrier group and a proprietary upper receiver that contains a reciprocating dual nested recoil spring. To accomplish this, Foxtrot Mike Products machined their upper receiver approximately 0.25 inches taller to allow for the spring and guide rod to fit where a charging handle would be placed in a standard AR-15. Removing the bolt carrier group is a little more tricky and requires a rod or punch to get the rear cap to slide out of the machined grooves in the upper. I will say that trying to reassemble the upper — I sent the guide rod and spring flying into my ceiling. While I was able to find all the parts, doing this out in the field could have rendered this rifle useless so be careful.

9 Folding Side Charger - Foxtrot Mike FM-15: Full Review
9 Folding Side Charger - Foxtrot Mike FM-15: Full Review
Recoil spring nesting in a taller deeper groove where a traditional charging handle would sit

Due to this taller proprietary upper receiver, aftermarket rails will not work with the FM-15. However, do not be dismayed. The lightweight M-LOK handguard is free-floated and gives a full 15″ of rail space to mount anything users may need. This rail also contains a machined slot to allow for the operation of the forward-placed non-reciprocating charging handle. The metal charging handle interfaces with a raised portion on the gas key of the carrier and can be angled up or down, or even swapped from the left to the right-handed side of the rail.

9 Folding Side Charger - Foxtrot Mike FM-15: Full Review
Forward placed charging handle

Utilizing a mid-length direct impingement gas system, this rifle runs almost identical to that of standard AR-15s. However, the FM-15 features a unique gas block that indexes to the barrel with an alignment tab. In addition, the gas block is also locked in place with two coil pins to prevent any movement or gas leakage. Running around 500 rounds through this rifle and mostly suppressed, the gas blowback seemed very comparable to that of other AR-15s.

Overall, this rifle comes in at 6.5lbs which is not bad for the size. The 16″ black nitride barrel is chambered in 223 Wylde, allowing the FM-15 “reliability with 5.56x45mm NATO & 223 Remington ammunition” and comes with a standard A2 birdcage flash hider. Throughout my testing, I have been impressed with the accuracy of this platform. I was able to get consistent hits at 500 yards as you can see on my Instagram page here. I also tried 4 different types of ammunition and had an average of about 1.5 MOA groups. Each 5 round group was shot from 103 yards, and I excluded one flyer from each group’s measurements. My groups are as follows: 

1.317″ (1.22 MOA) with 55gr FMJ-BT PMC

1.520″ (1.41 MOA) with 77gr BTHP Match Frontier

1.778″ (1.65 MOA) with 56gr FMJ Steel Cased VYMPEL

2.273″ (2.11 MOA) 62gr PMC X-TAC

9 Folding Side Charger - Foxtrot Mike FM-15: Full Review
9 Folding Side Charger - Foxtrot Mike FM-15: Full Review
9 Folding Side Charger - Foxtrot Mike FM-15: Full Review

Unboxing the FM-15 I noticed a sticker that said to break in the platform with 5.56 ammunition. Except for shooting groups, all of my testing was done with either 55gr 223 PMC or 56gr 223 steel-cased ammunition since I didn’t have any 5.56 on hand. While the FM-15 overall ran well, it was not without issue. Out of the box without adding any oil, I had several failure-to-feeds or FTFs.

9 Folding Side Charger - Foxtrot Mike FM-15: Full Review
Failure to Feed

After lubing the platform thoroughly, it ran better with about one failure-to-feed per every hundred rounds while suppressed. While I thought using a suppressor would simulate the pressure and blowback of 5.56, I guess it wasn’t quite enough for complete reliability during the break-in period. While the amount of 5.56 needed to break in the FM-15 wasn’t specified, I seemed to get better reliability after the first 200 rounds and some lube. The most persistent issue I encountered was that the bolt catch wouldn’t consistently lock back on an empty magazine. I tried both USGI steel, and polymer Magpul 30 round magazines, and only got the bolt carrier group to lock back 50% of the time. While not as critical as reliable cycling, it was still frustrating nonetheless. 

Utilizing what I think to be the coolest aspect of the FM-15, I shot it folded as well. I did have one jam while firing when the dust cover was up and hitting the folded stock. However, when I charged the rifle before folding the stock to make sure the dust cover was down and out of the way, I didn’t have issues with the brass ejecting over the stock. 

9 Folding Side Charger - Foxtrot Mike FM-15: Full Review
Dust cover hitting stock
9 Folding Side Charger - Foxtrot Mike FM-15: Full Review
Dust cover down behind the stock

Coming with three textured grip panels, a Magpul pistol grip, and Magpul Zhukov stock, the FM-15 is ergonomic and handles well. I think it also looks pretty cool and style points never hurt. 

9 Folding Side Charger - Foxtrot Mike FM-15: Full Review
Three included grip panels
9 Folding Side Charger - Foxtrot Mike FM-15: Full Review

The FM-15’s lower receiver has smooth rounded edges and incorporates a flared magwell. It comes with a plastic ambidextrous safety selector (feels flimsy), and an acceptable trigger for the price. It has a heavy trigger with spongy takeup but a positive and crisp reset that is right back on the wall and ready for the next shot. 

9 Folding Side Charger - Foxtrot Mike FM-15: Full Review
Flared magwell

Overall, the FM-15 is a neat new product that allows users to shoot with a folded stock. It was more accurate than I was anticipating, especially being currently available from Brownells for only $899.99. While I had a couple of jams throughout my testing, I wasn’t able to break it in with 5.56 ammunition like Foxtrot Mike Products recommended so I may be able to blame some of my issues on that. Either way, I had a lot of fun testing this rifle, and for the price this is not a bad option for someone trying to mix it up.


  • FM Products
  • MODEL: FM15–Select–
  • FM15
  • CARTRIDGE: 223 WYLDE–Select–
  • 223 Wylde
  • CAPACITY: NA–Select–
  • NA
  • BARREL LENGTH: 16″–Select–
  • 16″
  • FINISH: BLACK–Select–
  • Black
  • LENGTH: 35″–Select–
  • 35″
9 Folding Side Charger - Foxtrot Mike FM-15: Full Review

***Buy and Sell on GunsAmerica! All Local Sales are FREE!***

Leave a Reply

Your email address will not be published. Required fields are marked *

  • Michael July 29, 2022, 9:29 am

    I wanted one in 300blkout the minute I learned of them. Found one, put it in the cart, reached for the debit card and …. yep, far as I went. I was still on the fence about it until I read this article and I amazingly, I believe it’s the first time GunsAmerica SAVED me money.
    The proprietary parts, etc… just can’t see it for anything other than the cool factor for the AR platform.
    Awful expensive for a single shot, and/or potentially a club.
    I’ll keep my eye on ’em though and see what some passing time brings to bear in subsequent generations.
    Thanks FM for being innovative and forward thinking, and thanks GA for the review.

  • Nicholaus Carroll July 29, 2022, 8:03 am

    Firstly, the manufacturers start-up video clearly states that the “grease” inside the upper isn’t a lubricant and says that it is only a packing grease for the mechanism and should be wiped clean prior to proper oil/lubricant being applied. Failure to do so could lead to functioning issues.
    Secondly, the proper technique for removing and replacing the recoil spring is shown in the video as well and isn’t very difficult to do if you follow their instructions. I know, I have one. Honestly, if you’ve ever had to remove the spring work inside an M-60 machine gun in the field, and had that scewer of a rod driven into any location of your flesh, then this one is far easier and less of an annoyance.
    This upper works smoother and with less recoil that most of my other ARs in my opinion. It is lighter and less front heavy than any piston driven system, although unlike those you are still prone to a bit of heat and grime in the chamber,…just like any other DI system. I really do like this upper even with that old but familiar kink.

  • Foxtrot Mike July 25, 2022, 10:09 pm

    Hey man thanks for the review! The Zhukov rifle was the first we launched with over a year ago. Not locking back would leaves me to suspect it may have been under gassed while it was breaking in.

    We have made several changes to the platform, since we launched over a year ago. We would not be able to make our products better without consumers providing us this type of feedback.

    Understood on safety, we tried to offer consumers an ambi safety, which costs us about the same to make as buying a standard one. The paddles are open source too, if anyone wants to make

  • C. Lewis July 25, 2022, 12:06 pm

    Plastic selector? That’s a big no-no. Also what is the twist rate? What is the weight of the trigger? It seems like you left out a lot of very important information. I would like to see the results if it was broken in properly with the correct ammunition what type of groups and reliability you might have from that. But hey it looks cool so I’m sure a lot of people will buy it just because of that.

  • Derek F. July 25, 2022, 8:36 am

    I have had my FM 15 for about a year now. I like novelties in weapons and paid a full price when FM15 hit the market. But I don’t mind it since the rifle is worth $1000 to me! I have not had any issues with the weapon whatsoever! No issues with the stovepipe, extraction, and ejection! Before I took it to the range first I had to remove the corrosion coating first and then lubricate it. I have shot to more than 2000 rounds, mostly 5.56 in 55gr and 63gr, both suppressed and unsuppressed. The mechanics of this evolution of AR are very interesting and well made. I get consistently 1.5 MOA with XM193 ammo. I am very happy with this weapon!!! Brownells has it for $799 for sale now. And it is a steal at this price!

  • Mike V July 25, 2022, 7:51 am

    “I didn’t have any 5.56 on hand”…

    I don’t get it. The manufacturer says to use 5.56. You have a nice scope and a suppressor, getting your hands on a few hundo 5.56 shouldn’t be much of a challenge.

    Considering its unique adaptation of the traditional AR, and that you intended to use it suppressed, it would seem reasonable to lube it and feed it per factory recommendation.

    Why did we do a review on something like this deliberately hamstringing it out of the gate?

    • Mick July 25, 2022, 3:53 pm

      I happen to know if you do do exactly as FM Products recommends during break in, you can mess up a firearms reliability. I have an FMP9 and it was my first pcc and it’s a good pistol, if It was stolen, I’d buy another, that’s good.

  • Greg Webb July 25, 2022, 7:27 am

    $ 900+ for a complete upper with reliability issues?
    I don’t think so!

  • Lee S. Castor July 25, 2022, 4:49 am

    Through it down into the mud and then shoot it. Please report back and tell us how that went for you.

Send this to a friend