JK Modular Solvent Trap Kit
Courtesy Silencer Shop
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Before building your own NFA item, you have to file an ATF Form 1. That involves the same $200 tax and registration process as the Form 4 that’s filed when purchasing an NFA item from a dealer, but the approval times are significantly faster. In fact, for quite a while now eFiled Form 1s have been consistently approved in just 2 to 5 weeks.

Since making your own silencer and navigating the ATF eForms system is difficult, JK Armament and Silencer Shop have partnered up to help on both fronts.

JK Armament’s Modular Solvent Trap Kits (for pistol or rifle) are not controlled items — they’re just aluminum cups design to catch cleaning solvents coming out the muzzle of your firearm. However, should you drill through those cups in order to create a bore through which a bullet can pass, it becomes an effective silencer.

JK makes the physical drilling of the MST cups easy and foolproof with their Drill Jig Kits. Nothing more than a hand drill and a bench vise are required to produce centered, concentric bore holes in the cups.

(Read TTAG’s easy guide to buying a silencer here.)

To make this process legal, Silencer Shop is providing Form 1 filing service for just $34.95 (you’ll still have pay the ATF your $200 tax). They take care of the hard stuff and ensure that everything is filled out and filed correctly for you.

Just don’t forget…Form 1 approval is mandatory in order to legally turn a solvent trap into a silencer.

JK Armament’s and Silencer Shop’s press release follows:

JK Armament and Silencer Shop ink deal for Pistol and Rifle Modular Solvent Traps.

JK Armament and Silencer Shop announce revolutionary Modular Solvent Traps (MSTs) available exclusively on SilencerShop.com or through Powered By Silencer Shop dealers.

Effective immediately, all JK Armament Modular Solvent Traps, accessories, and tools will be sold solely through Silencer Shop. Additionally, with every MST purchase on SilencerShop.com, Silencer Shop will offer an optional eForm 1 service.

Form 1 qualified, configurable in any length, and multi-caliber, JK Armament’s Modular Solvent Trap is designed for pistol or rifle adaptation. The pistol model supports traps on 9 MM, 45 CAL, and 10 MM; whereas the rifle model supports 22 LR and 30 CAL traps.

“Silencer Shop is excited to be carrying JK Armament. Jake Kunsky has built a really awesome product with a wide range of applications. Plus, JK’s Modular Solvent Traps are form 1 qualified. Who wouldn’t want that besides Nancy Pelosi?” says Dave Matheny, founder and CEO of Silencer Shop.

“We are excited to supply customers with a unique tool that is tough and modular, and able to tackle any job a solvent trap could be asked to do,” states Jake Kunsky, owner and operator of JK Armament.

About JK Armament Widely known for their Jake brake, JK Armament has acclaimed recognition within the firearm industry for pushing the seams with innovative technology. Jake Kunsky, the founder of JK Armament, has over 20 years in the industry, including hands-on experience during combat deployments and weapons development with companies such as Gemtech Suppressors and Maxim Defense.

About Silencer Shop As the industry’s largest suppressor distributor, Silencer Shop’s goal is to supply customers with a suite of services that allow for a simpler silencer ownership process. With the most trafficked suppressor website, a robust nationwide network of kiosks, and ATF compliance and customer support, Silencer Shop provides the most efficient process of acquiring NFA items.

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  1. Interesting. The rifle package was $499 when I went to the Silencer Shop site. Where’s Jay with his testing for safe hearing?

    • $499?

      So in other words only about $100 less than a real silencer made out of something thats probably a lot more durable than aluminum cups threaded together? got it (headscratch).

      This is even more pointless than when Sig Braces used to cost more than just paying the tax and registering a lower, because at least then you could make the argument that you didn’t have to register a pistol with a brace on it. Not the case here since you have to register this to “legally” use it.

        • meh… you’re going to own the thing for the rest of your life, how long I have to wait to get it up front never really factored into the buying decision for me.

          I’ve bought 4 silencers to date; they have taken anywhere from 6 months to 12 months. It’s less than ideal, but after about 2 months of waiting you sort of forget about how long you have left and then its almost like Christmas when the form comes in.

          On none of my purchases would I have opted to pay almost the same money for something a significantly lesser quality just to have gotten it sooner.

        • If you file electronically and send in your fingers prints in the mail, it is still this short of a wait period on any suppressor, not just these.

        • Michael that’s not true. E-File Form 4s haven’t been available for many years and the wait time is still usually 8 to 10-ish months.

          If you’re talking about any other suppressor you build yourself, well, yeah. ANY eFiled Form 1 has been taking just a few weeks. That includes making an SBR and whatever else, too.

    • Texas. Nobody cares. BATF hasn’t prosecuted illegal supressor for …. Not used in crimes. Gun mufflers don’t work that well, except .22, .45 ACP, Subsonic 9mm, and 300 sub sonic Black Out (which is 38 Spec. in performance). Easy to set new precedent in court. Citizens are entitled to “well regulated”, and waiting 12-18 mos. wait isn’t well regulated. NFA obsolete. Modular Configuration Rifle (AR) kills it. BATF gave up on SBR’s by allowing braces. 14′ shotgun as “any other weapon”. Have to understand NFA was written to add time to criminal’s prison sentences. If you aren’t a criminal, nobody cares. Quit being paranoid. You can buy FA trigger pack from HK parts for $50 complete. Grinder, and drill, your HK clone is…. Make a FA M16 with coat hanger, and M16 hammer. Binary triggers let you run 175 RPM. BATF would shut these guys down in New York, if they cared. Just don’t be caught robbing a storewith one. Gets you another 5 years.

      • Newbie grandma here,….so are you saying it’s not a big deal just to buy these solvent traps and put them together without going through the forms and I won’t get in trouble? I just want something that I can use on a 22lr handgun to quiet it ( i know they aren’t supposed to be that loud) because I have tinnitus(constant ringing in my ears) and don’t want to bother with muffs, especially since when I finally do get to practice, there’s liable to be others around. Will I be hunted down somehow?

        • I think what they are saying is the ATF have better things to do than actively go after people who are not currently involved in criminal activitys. It’s still illegal no matter what and you should never construct an NFA device without filling out and receiving a tax stamp untill the law is changed. Don’t let anyone talk you into it otherwise. Dont be the ATF’s first case no matter how long it’s been since the last one

    • Well what do you expect from a state run by Democrats and Nancy Pelosi leading the pack. Frigin socialist commies anyway!

      • California’s gun laws started when Reagan was governor. The Mulford act was even named after a Republican. Governor Ronald Reagan, who was coincidentally present on the capitol lawn when the protesters arrived, later commented that he saw “no reason why on the street today a citizen should be carrying loaded weapons” and that guns were a “ridiculous way to solve problems that have to be solved among people of good will.”

        Fear is what leads to gun control.

  2. Solvent traps were some hot water just a few years ago, what’s changed? I’m kinda shocked to see this on the front page of TTAG.

      • I see.

        Well, legal or otherwise, I certainly wouldn’t order one of these puppies online. Cash is king and its cheaper than replacing all this nasty carpet too.

        • Strange thing is, I’ve never seen one of those on a table at a gun show.

          …it’s almost like the advertisements for them are a set-up…

        • There is a vendor who has them at some shows in my area, prominently displayed, along with what is labeled as “full auto replacement” (or something like that) trigger parts. Nice lady and I always enjoy talking with her when I see her. She is always careful not to cross that line when talking about these products. But, clearly giving a big FU to the gov. She says ATF and LEO watch her fairly closely. I always buy some AR small parts from her and figure that the folks who buy ‘traps’ end up with a picture of them being taken and license plate from their car being recorded.

    • @ Arc: Ditto that. Anyone buying something called a ‘solvent trap’ and who doesn’t immediately file a form 1 can expect a visit from the ATF eventually. $499 is some pretty expensive jail bait.

    • That’s fine too, but you might be waiting a year or longer for the stamp. This kit is so you can apply for a form 1 and not wait more than a few weeks for that stamp. I don’t have any NFA goodies, but I have a friend with a trust. He had a .22lr sbr and can that took 2 years, while he got 3 other cans in 4-8 months during that same time frame.

  3. With “constructive intent” having been used to charge people for SBR’s that havent been built, why wouldnt they come after you the same way for one of these still in kit form?

    Genuinely curious why the same couldnt happen if I decided to buy one of these and LEO of some flavor shows up before I’ve turned it into a legal silencer.

    • Agreed, I wouldn’t even order the parts unless I had a warm, signed, tax paid Form 1 in my hands…. but I have several bought the other way, some from Silencer Shop made by names we recognize and machinists and warranties to back it up and did the fingerprints, photographs and background check.

      • Frankly, at least as per my understanding of this stuff today, that’s where my comfort level is as well. I’d want to have them hold onto the entire kit until my Form 1 was approved and then ship the kit to me at that time.

        • That would be wise. The ATF sayeth in Publication 5320.8:

          “Note: Under no circumstances may the firearm in question be made prior to receipt of the approved Form 1.”

          Sounds like a line I would not want to argue about crossing.

        • Well the problem for the ATF when it comes to solvent traps is Solvent traps have an intended purpose already. When you apply for a form 1 you don’t have to provide any schematics of what your building it out of just basic dimensions. So as long as you haven’t done any modifications to that ST you could be constructing that suppressor out of anything. The only way they can prove intent is if you were to modify the ST. So they are perfectly legal to own just watch where you buy them from.

      • I think it would be hard to prosecute for constructive intent when you paid the tax and where just waiting for the form 1 to complete the build. This is because paying the tax is saying YES I plan to build a silencer. And paying the tax BUT not completing the build pretty much proves you where not evading the tax.

        This isn’t like a transfer where you have already done some something. And it’s not like having parts without a form 1 filed which shows you where possibly trying to break that law.

    • Because the only purpose weapons parts have is to be placed on a particular weapon. Therefore if you have the parts to assemble that particular weapon the ATF can say you intend to assemble them. Where as a solvent traps purpose as purchased is for weapons cleaning its much harder for the ATF to prove you intend to build a suppressor until you drill out the holes for a bullet to pass through. That’s what was getting some people in trouble that were ordering solvent traps from Alibaba and wish. The traps they were ordering were pre-drilled and therefore couldn’t possibly be used for retaining solvent fluids as designed and could immediately be mounted and used as a suppressor there by providing the ATF to show you had intent for it to be nothing more than a suppressor in the first place.

  4. I don’t know why they don’t just call it an 80% silencer kit or similar. The pistol versions seem limited since they don’t have a Nielsen device or recoil booster. Fine for a PCC or fixed barrel.

    • That’s the point of using the industry-standard 1.375×24 mount threads. There are a half dozen or more boosters on the market that will fit this kit, and Silencer Shop carries a handful of them.

      • Jeremy, does TTAG have a form 1 silencer article they can post with the specifics of how to do it right?

        • Soon! I’m getting one of these kits and will document the process.

          But, really, there isn’t a lot to it. When you get the Silencer Shop Form 1 service you input the information they need from you (and they already have most of the necessary info) and they file all of the paperwork. When you’re approved you drill the bore holes in the MST and you have a suppressor. With the 1.375×24 mount threads there are TONS of mounts available that will fit this thing, from fixed mounts to QD brake mounts to boosters, etc. And it comes with a direct thread mount.

        • WHO can you talk to on the PHONE about the particulars of this Solvent trap to Suppressor conversion and its numbers and performance?

    • Because if they call them silencer parts they have to be regulated like silencers (any part of a silencer is a silencer according to the NFA).

      Therefore they have to advertised for a different legal purpose, like dry storage or trapping cleaning solvents.

  5. I thought the ATF had made illegal for anyone but a licensed facility/manufacturer/gunsmith to work-on/build/repair a suppressor, regardless of whether one wants to prepay the $200.

    • You can make a silencer if you pay your $200 tax and get an approved Form 1. The background check is the same one they do for regular firearms purchases. They department processing the forms is just small, so it takes forever.

      The Form 1 is permission to make any NFA item (except machine guns). Similar to how the Form 4 is to transfer NFA items.

      They have an electronic processing system for Form 1s that makes it a lot faster than Form 4s, which are still paper only.

    • It’s legal for you to make your own suppressor granted you have applied for and gained permission from the ATF on a form 1. It isn’t however legal for you to build suppressors for other people and sell them. That is for a manufacturer with the proper licencing.

  6. Waaaaaay too many hoops and too much hoopla and too much money to want one. From whisper quiet hammers to knives to crossbows there are no tax stamps or anal exams to possess, etc.
    A can is nothing but a glorified lawnmower muffler that I can live without thanks to some people laughing all the way to the bank.

    • You pick any serial number you like and file it on the Form 1. Once you get your tax stamp back approved you have to engrave the maker’s name (or trust name), city, state, model name (that you make up), caliber, and serial number on it. I assume this only goes on the base tube the extra baffles connect onto.

    • The issue of making it longer is somewhat complicated. The NFA and GCA together appear to say that changing the dimensions of a silencer (making it longer or larger in diameter) amount to the manufacture of a whole new silencer, requiring a new Form 1.

      In this case, where you can easiliy screw on a new modular piece and lengthen it… or remove a piece and shorten it, well, that’s an interesting question.

    • Shorter is ok, longer is not. You will put the longest configuration as the length on your form 1. As long as it never gets longer than that you’re ok. If for some reason it permai becomes shorter than that length you should notify the ATF but no response or other action is required.

  7. By the time you are up the extras (jig, mount adapter, etc) you’re paying up to around $1000 for a can made out of aluminum that you made yourself. That does not include the paperwork fees or tax stamps.

    That’s right up there with commercial cans made from Inconel or titanium.

  8. Folks should be aware that the ATF has very specific marking requirements for NFA items. These issues include not only the information from your Form 1 that has to be put onto a device like this, but also the size of the letters, the depth of the lettering, and how that depth is measured. ATF Publication 5320.8 states in section 7.4 the size (1/16th of an inch, minimum) and depth (0.003″ minimum) of the lettering used to ID a NFA item.

    People should also know that if you don’t have the capability of performing the marking yourself, and you take it to a shop to have the markings put on (eg, with laser etching, which is a good way to do this), if the shop isn’t licensed for work on NFA items, you have to stand there and watch them do it. You cannot leave it with them.

    I’d recommend that anyone making one of these read up on all the issues in ATF Publication 5320.8. You can download a PDF copy of this from the ATF.

    • Wow. So much bad information, and all in one place. Kind of a one-stop-shopping for incorrect or misleading info.
      1. “ATF Publication 5320.8 states in section 7.4 the size (1/16th of an inch, minimum) and depth (0.003″ minimum) of the lettering used to ID a NFA item.” Wrong, or at best, misleading. Only the serial number needs to be 1/16″ minimum (Section 7.4.1 Serial numbers). The other information (maker, model, etc.) has no minimum size specified, just a depth. (Section 7.4.2 Additional information).
      2. “… if the shop isn’t licensed for work on NFA items, you have to stand there and watch them do it. You cannot leave it with them.” Again, at best misleading. You can have the item engraved before it’s converted into a silencer. It can be left with anyone at that point. In addition, there are numerous companies that specialize in engraving NFA items; Tar Heel State Firearms is one such company. Fast, cheap, hi-quality engraving that runs $30. Hardly a barrier. In addition, many people (who don’t care about looks, evidently) have and continue to engrave their own items with a cheap engraving tool or even a stamp set from HF.
      3. “You can download a PDF copy of this from the ATF.” The only totally accurate statement in your post.

      Tons of people are using solvent trap parts to legally make suppressors, and the steps to do it legally are simple and brief. Yeah, the cost of this modular version is higher than alternatives like QB, but it’s unique and innovative, and with eFile for your Form 1, you can go from no can to a pretty nice can in about 30 days, something you just can’t do (but should be able to) with a Form 4.

        • Why can’t anyone do the markings? They should be made before you send the form 1 off anyway…and in that case nobody is working on a suppressor. They’re working on a completely unregulated solvent trap.

  9. As of a couple days ago, these are sold out at Silencer Shop and they don’t know when they’ll get more.

    • Go to http://www.solventtrapcups.com and order on of the 10″ traps they have and add a QD mount that will get you very close to the 13″ without going over they also have a 12″ kit there as well if you wanna push the envelope. They have them in Aluminium, Stainless Steel and Titanium.

  10. Wow lots of comments and opinions here. Which is fine, but I wonder what makes a person leave a negative comment about a new product. In this day and age you can’t really trust much you read on line. So may agendas and ulterior motives. Feel free to say the same thing about me. But my 2c. I don’t know this guy from Adam but I think he has an innovative product, which has a niche market. For example, my use of a suppressor has more to do with reducing the visual flash signature of the weapon, not necessarily the noise signature. So in this respect, this is a good choice for that. I am not looking for really good sound suppression, but good flash suppression, along with some noise reduction. So it’s performance in comparison to factory cans is irrelevant to me. I also might be looking at the time savings/convenience in getting it papered. And the end cost may not be a factor. Being able to purchase individual parts each month like an installment plan, might be more important. So sure while some have brought up valid points, I think these points are just as valid. It’s not for everyone, but it is for some, as the sold out status indicates.

  11. It’s sad when people are arguing about the price. THEY WANT YOUR SIGNATURE AND FINGERPRINTS. I will NEVER give away any paperwork as that is submission to their jurisdiction as a second class, inferior “U.S. Citizen”. UPGRADE to first class “state Citizen” and NEVER be part of the limited jurisdiction of D.C., NEVER pay IRS or be involved with ATF as you become a FOREIGNER, a NATIONAL. My goodness people… come out of her, Babylon!

  12. These things have been around in one shape or form for a long time. All you people saying you order and you’ll have people knocking at your door. It’s all bull shit, I’ve know several people that have used and had them for a long time and ordered kits from multiple places and has never had an issue. If your an idiot and you do stupid stuff you’ll get in trouble. My suggestion is if you drill it make sure you get your form done first. The cool things are that if a part wears out then you can simply order a replacement part and your back up and running. If you have an issue with a new one you have to send it in and wait again.


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