I’ve seen it said numerous times that some of the easiest clones to build are the SOPMOD clones. Whether it is or isn’t, building one might not be easy or straight forward to a person that is new to cloning service rifles. Are they hard to build? Absolutely not, but finding some of the parts can get complicated and there is a lot of information about these rifles to dig through.

My build almost didn’t start. I had my heart set on cloning a Mk18 Mod 0, but at the time the SBR thing had me shying away. I saw a couple good deals on some parts that would work great for a SOPMOD build and bought them up. The intention was to just sit on them. If you plan on cloning, then start collecting GWOT parts. You never know when you can trade, sell, or use them.

Once I had the stock and a couple minor parts in hand the bug bit me in a big way. At that point I wasn’t totally set on cloning, but that changed fast. I will always suggest that you should never go broke when building a rifle. If you cant afford it, then don’t do it. Typically I find a way to do what I want. It usually involves time, saving money, networking, trading parts, or something to keep me from going broke. After I started hitting AFCOM and looking at the SOPMOD clones, budgets and all sense went out the window.

This is exactly how trouble starts…

What Block?

Block refers to what set of equipment you are using on your rifle. Block I and Block II are two completely different sets of equipment. Theres also a Block 1.5. While I’m not going to cover the differences right here, I will in a later post.

For me the Block I equipment just wasn’t as visually appealing (except when on a Block 1 Mk18) and I wanted something that was a bit different than a run of the mill M4A1. Going Block II would give me a few things like a free floated hand guard, the ability to run a Surefire can, and EO-Tech becomes an option, ect. Not only that, there is a FSP (front sight post) version of the Block II SOPMODS.

All that said, if your build is an as issued build, then you’re pretty limited to what you’re going to run. My build is more of an as seen in the wild build. Essentially meaning that if its been seen or is commonly used on the rifle (but not issued with it), then its fair game to run on the rifle. I didn’t stray far from an as issued build, but I did run a few minor non-issued parts.

The Meat and Potatoes

So what goes into the Block II SOPMODs? There are a ton of good resources for clone info out there. ARFCOM has great threads on various clones. Most of these threads have parts lists. Clone Rifles is also an awesome reference for builds. Those two places are great for figuring out the ins and outs of most clones and what people consider kosher.

It took quite a bit of research to get a good feel for what I could use and what I wanted to use. There are some nuances that you might not catch if you don’t take your time and do your home work. Like that most of the time the FSP guns got SOCOM barrels where as the non-fsp guns were more than likely Gov profile barrels.

I’ll start with the lower and work my way up.

Almost fully outfitted. While sexy as hell, its not always necessary nor needed.

The Lower

Lets get one thing clear right off the bat. A full auto Colt lower is not in the cards for most all of us. What is considered acceptable and the next best thing would be a Colt LE6920 lower. Even better would be a “Property of US Government” marked lower. The grip used will be an A2 style grip for an as issued build. For a seen in the wild build most major brands you can name off the top of your head associated with work guns have probably been used.

The small parts should all be Colt. In fact, the easiest way to build this clone is to start off with a complete Colt LE6920 lower. This is what I did and it saves you the hassle of tracking down lower parts. Getting a complet LE6920 is also a great option to build off of. As far as the buffer tube, spring and buffer goes, they should also be Colt. Mine has a Colt 4 position buffer tube, standard Colt spring, and a Colt H1 buffer although I’ve read an H2 might be the more correct way to go. The trigger should be either a Colt mil spec trigger or a Geissele SSA/SSA-E. I ended up with an SSA-E because I am a trigger snob.

Much like I said with grips, many stocks have been seen on these guns. I’d say that the most common that I’ve seen have been Magpul, Colt, and LMT. Mine got an LMT Gen 1 SOPMOD stock. It was not cheap, but it was well worth the money and it has that iconic look.

Its all about the details. With that said, you cant forget the UID label. Carolina Laser Works does the best UID labels I have seen and at a reasonable price. Hes great to work with as well. The correct UID label for a Block II SOPMOD requires 3 things. The cage code, part number, and serial number. For a Colt gun the cage code will be 13629. The part number will be 12972700. The serial number would be the serial number of the gun. There are different UID labels for different things, some containing different info, so make sure you get the right one. The one needed will be for Colt M4’s and M16’s.

The Upper

The upper itself should be a Colt upper. What gets tricky is the forging marks. There were numerous forgers of Colt uppers. For most people a Colt upper will do, period. I have a Colt cage code upper, however, a Cerro forge (key hole forging mark) or Alcoa Forge (AF forging mark) with the Colt C will definitely be more desirable for the hardcore crowd. This is especially critical if you’re wanting a period correct gun. In fact, any manufacturer locations and markings throughout the whole gun become important at that point. This makes parts incredibly hard to find as well.

Your BCG should be Colt. If you want to get really correct, then you should look for a BCG with a C stamped carrier. The bolt itself should be MPC marked. Some bolts also have a white dot. Getting a bolt with all 3 is getting harder and harder. Mine has a C stamped Carrier with an MPC marked bolt.

The barrels are 14.5″. They came in two profiles, SOCOM and Government Profile. The SOCOM profile is most appropriate on the FSP variant of the gun, where as the gov profile was used on the non-FSP version. The muzzle device used is a Surefire 4 prong flash hider. They can be hard to get your hands on and incredibly expensive. For the non-hardcore crowd, the Surefire 3 prong is readily available and might be acceptable. Also, you will either need a tax stamp or have your flash hider pinned and welded as the barrel is shorter than 16″. I opted to pin and weld my SF 4 prong.

The handguards used are both the Daniel Defense RIS II and RIS II FSP. I chose to go with an RIS II FSP because FSP is life. I’ve always had a thing for FSP guns. It is purely personal preference. Neither way is wrong or right. These are the only two acceptable handguards though.

The charging handle is also a simple matter. You’re clone correct in most peoples eyes so long as you run either a Colt charging handle or a PRI gas buster. I opted for an FDE PRI gas buster on my rifle. I do not like the Colt charging handles. I’m sure that for your “as seen in the wild” builds you will find pictures of many other charging handles out there.


There are numerous optics used out there. I’d say probably the most common and my personal preference are EO-Techs. Both the 533’s and the EXPS3-0’s were used. On mine I opted for the 533. Here is the kicker, finding an EO-Tech with the proper SU-231 or SU-231A markings. If you cant find one, then you can either neglect that small detail or get it engraved. A quick Google/Forum search will reveal that G23 and G33 magnifiers were some times also used.

Those aren’t the only options though. Elcan SpectreDR 1-4’s with or without Doctor sights, Aimpoint T1’s and T2’s as well as Comp M4’s were also used. Various LPVO’s were used as well including the Leupold Mk6 1-6 and Vortex Razor HD Gen 2 1-6. Various mounts were used, but one of the more common ones seems to be Geissele’s mount. That being said, pictures have surfaced with all manner of LPVO’s. There is even talk about Strike Eagles, although I have not seen those pictures. I’m sure that some one could dig them up and use that to justify their “as seen in the wild” build.

As far as BUIS goes, typically you see one of two things. KAC BUIS or Matech. I have a FSP on my rifle. I ended up using a Matech for my rear sight as you see them all over the place and they are cheap. The KAC BUIS tend to be spendy, but they are very nice. I’ve only owned the rear KAC BUIS, not the front, and I have to say that they are very nice.

Lights and Lasers and Grips Oh My…

The only two grips that were issued that I know of are the KAC and the Tango Down grips. The Tango down came in both full size and short. I run the short Tango Down VFG’s because I don’t actually grip them. You will see many different kinds of VFG’s out there in the wild though. So your “in the wild build” has many options

Lights are kind of a weird subject. The only two issued with the rifle that I’m aware of are the Insight M3X and the Insight WMX200. Various Surefires have been used though. In fact, Surefire has had contracts for their lights. The light I ended up using was a Surefire M620V. That particular light fell under the VBL-III contract if I remember correctly. Either way, you’re safe with most Surefire lights. The WMX200 and M3X are expensive as hell and hard to find. When I say expensive I mean EXPENSIVE! I’ve seen them go for $750+.

For lasers and a Block II gun, you options are the LA5, Peq-15, and Peq-16A. The acceptable alternative is the ATPIAL-C. Its cheaper and you can actually own it. It’s the low powered version of the Peq-15. Getting your hands on a full powered laser is a touchy subject. Its one I would have to research as the laws aren’t totally clear. All I know is that the restricted lasers are controlled by the FDA. Either way, the safest bet is the ATPIAL-C. No dealer is going to sell you a restricted laser unless you are military or law enforcement and if you get your hands one one that fell off of the back of a truck, then you might very well get a knock on your door. I’m not kidding. A short Google search will reveal that it happens.

With that said, you’re looking at a lot of money and you can find pictures of Block II SOPMODS without lasers. So going without one isn’t a big deal. In fact, if you don’t have night vision and don’t plan on it, then don’t waste your money. You’re looking at well over a $1300 on the cheap end if you do take the plunge.


Suppressors are fun. There are two cans commonly seen on the Block II SOPMODS. The Surefire SOCOM RC and the KAC NT4. I sprung for a Surefire SOCOM RC. It is still currently in NFA jail at the time of writing this though. I did get to use Ivan from Kitbadger’s 7.62 Surefire can on my gun when I went and trained with RuneNation. It was the first time I had used a can and it was awesome. The experience was valuable to say the least. I learned that you might want to hit the gym if you hang a bunch of crap off the front of your rifle and that you get used gas blow back real fast. Despite those two things, saving your hearing is key to living a healthy happy life. Trust me… My career has had an impact on my hearing and any amount of hearing loss is frustrating.

Slings and Things…

Slings are another one of those things that, if you look hard, you’ll see people running many different types of. I’ve read officially that the Blue Force Gear Vickers slings are used. I personally have been running and prefer the Vickers slings. The way they adjust is very stream lined and easy. They also come padded or unpadded.

As far as the actual sling mounts themselves go, the CQD mounts are the ones officially used. I’m running both the CQD end plate mount and the picatinny mount on my handguard. If you look at pictures you’ll see all manner of attachment points. KAC has a nice QD mount for your stock that I’ve seen quite a bit, but it is expensive. Again, just dig through pics taken over seas and you will see that guys ran a lot of different stuff.

But How Does It Shoot?

As equipped my Block II SOPMOD is a smooth gun. It is definitely more accurate than I am. I’m used to my Dissipator and the Dissy is the more smooth and softer shooting rifle, but this Colt is very nice. Much more nice than a lot of other stuff I’ve shot. Keep in mind that I haven’t been able to get my hands on a Knights Armament or anything like that yet though.

The gun is easy to shoot, very accurate, and has all the bells and whistles one could want. There’s a catch though. This thing is heavy as hell. The saying, “do you even lift bro,” often comes to mind when I pick this thing up. Ultimately its shootable, but it’s heavy enough that it will wear on you throughout the day if you’re shooting it for long periods of time.

If you’re thinking about getting into cloning, then there are easier guns to clone (see Block I SOPMOD), but this wasn’t that bad and it is very satisfying. With Colt no longer selling rifles to the civilian market you can expect some price gouging and that Colt parts will get a bit harder to find. Some of the other parts such as the SF 4 prong can be hit or miss. The handguards are around if you look and you can typically find a decent deal on them if you’re patient. That seems to be the way cloning goes though.

If you do plan on attempting one, then here is my advice. Start a clone fund. As with all clone rifles, if you’re patient you’ll run across good deals on expensive parts. If you don’t have the money right then and there, then you’ll miss out. Keep that fund stocked and don’t touch it unless something like that comes up. Use other funds for rest of the time. Also, don’t go broke doing this. Its not worth it. You’ll find a way to save money or make it happen. Again patience is the key. Most people don’t throw these things together fast. It took me well over 6 months to collect parts and get a gun together that shot. It took even longer to get the rest of the stuff for the rifle.

I’d definitely say that this is probably easier than most clones to build though. There aren’t really any odd ball parts, parts that are so far out of production that it would take a miracle to find, and in general the parts are still reasonably common. The assembly of the gun itself is also easy… I mean its an AR-15. I’ve got more on building AR’s coming up soon. If you’re interested in cloning, then I’d definitely say that either the Block II or Block I SOPMODs are the place to start.