American gun laws are a bucket of snakes. We committed gun nerds live amidst a veritable minefield of labyrinthine regulations all designed to make it more difficult to exercise our quirky little hobby. Folks like Nancy Pelosi and Chuck Schumer often can’t reliably tell the difference between someone who produces a top-quality gun magazine (Athlon Outdoors) and someone who produces a top-quality gun magazine (Magpul). In their defense, it is indeed complicated. However, our side isn’t trying to put the other in jail if we fumble the details.

DIY Suppressor Wipes at Home

There are somewhere around 3 million sound suppressors in the NFA (National Firearms Act) registry. That number climbs every single day. Nowadays you really can’t eat at the cool kids’ table at the local range unless you have something long and sinister dangling from the snout of your favorite black rifle.

Sound suppressors themselves are quite literally harmless. Heck, you can buy rimfire suppressors over the counter and uncontrolled in France. That’s just embarrassing. However, the bigotry of the uninitiated conspires to make ownership difficult over here in the land of the free and home of the brave.

As an aside, sound suppressors desperately need to be deregulated. You and I know that silencers don’t make your guns any extra special deadly. They just look cool and make you a more neighborly shooter. They really should be sold out of vending machines at your local Quik-E-Mart. 

Rules

The BATF often paints itself into a regulatory corner. Given the illogical nature of the laws they are tasked to enforce, that is almost inevitable. A great example is suppressor parts.

Right, wrong, or otherwise, the BATF is tasked with keeping sound suppressors away from anybody who doesn’t live in one of the 42 states where possession is allowed and hasn’t endured the administrative gauntlet required to buy one legally. Suppressors are actually fairly easy to make. In the face of such draconian regulation, however, somebody someplace apparently tried to sell individual components through the mail that could then be illegally assembled to create unregistered sound suppressors. Uncle Sam was having none of that.

As a result, the BATF not only regulates sound suppressors but also suppressor component parts. Here’s the specific verbiage, lifted directly from the BATF website, “The term Firearm Silencer or Firearm Muffler means any device for silencing, muffling, or diminishing the report of a portable firearm, including any combination of parts, designed or redesigned, and intended for the use in assembling or fabricating a firearm silencer or firearm muffler, any part intended only for use in such assembly or fabrication.”

That sounds great on paper. However, you can build a serviceable sound suppressor out of PVC pipe and fender washers. Does that now mean that your local Home Depot is awash to its gunwales in unregistered suppressor parts? Well, yeah, kind of…

And therein lies the rub. If you fail to cinch your can down tight and damage the baffles you can’t just drop by the local gun shop and pick up replacements as you might any other gun part. Those components have to be exchanged one-for-one by the manufacturer to remain legal. That’s potentially frustrating. However, the really big deal is disposable suppressor wipes.

A Wee Bit of Science…

To be effective, sound suppressors must cool and slow the hot gases escaping behind a bullet once it is fired. To do so, most cans incorporate a series of baffles or similar mechanical structures that disrupt all that chaos until it can escape into the environment in a cooler, less chaotic state. However, that hole in the end will always be a problem.

The technical term for the opening in the far end of your sound suppressor is the exit pupil. The larger the exit pupil, the more noise can escape. For this reason, small-caliber weapons are typically easier to suppress than big gaping .45’s. One solution explored early on in the evolution of suppressor design was to seal the end of the can with some kind of relatively soft disposable material through which the bullet might pass. These are called suppressor wipes.

A decent wiped suppressor typically better manages first-round pop than a more conventional design. They also reliably produce less perceived noise. Most cans, particularly those not mounted on precision platforms, could potentially benefit from their inclusion. 

Examples

The Navy SEALs used a specially-modified S&W Model 39 9mm pistol in Vietnam designated the Mk 22 that included a very effective sound suppressor. The Mk 22 can incorporated disposable rubber wipes. Several companies offer new-production wiped suppressors today. The Dead Air Ghost, the Gemtech Aurora-II, and the Energetic Armament VOX-S are but a few. In particular, wipes make small low-volume concealable cans more effective.

Mitch WerBell’s SIONICS 1970’s-era two-stage MAC-10 suppressors are likely the most common examples of wiped designs. These iconic cans incorporate an initial high-volume stage filled with, of all things, shoelace eyelets. There follows a series of baffles. The far end is then sealed with a consumable synthetic wipe to help seal off the exit pupil. 

In addition to occluding the exit pupil, suppressor wipes lend themselves to the addition of an ablative material like wire pulling gel, shaving cream, or suppressor foam to further enhance their effectiveness. Though terribly messy, the addition of these materials can make a profound difference in suppressor performance. Fill the can from the rear, and the wipes help hold all that stuff inside until the gun is fired. 

A decent wipe will typically only last between 20 and 200 rounds. Weird rules or no, it is really impractical to expect American consumers to package up their NFA-controlled item and ship it back to the factory for a recharge after every box of ammo. The BATF’s solution is to allow individual FFLs to do the swap-out. I have maintained an FFL myself for more than fifteen years, and I have no idea how to do that legally. The obvious solution is to just make your own.

DIY Suppressor Wipes Process

Suppressor wipes can be made from neoprene, silicone, or urethane. When I bought my vintage SIONICS MAC-10 suppressor a few years back it came with half a dozen original wipes, all of which had dry rotted into powder. The one already in the can held together for a couple of magazines but it disintegrated in short order. Those two mags, however, were fairly amazing. I simply had to find a replacement. One need look no further than Amazon.

There I discovered ¼-inch heat-stable silicone rubber by the sheet as well as a plastic cutting board to ensure reliable consistent cuts. You could theoretically cut this stuff out with heavy scissors, but it would be ugly. The answer was a heavy duty hollow hole punch set with nine different hole cutters. 

This thing consists of a common shaft and interchangeable cutting heads of various sizes. It is designed to cut leather but does a simply spanking job on this silicone rubber as well. I opted for the set so I could also cut small starter holes in the center for the bullet. The whole rig looks like something you’d purchase at Harbor Freight Tools and should last me several lifetimes.

Sizing the Cutter

I also picked up an appropriately-sized flat washer from Home Depot to help keep things centered. Making wipes involves sizing the cutter head to match the interior diameter of the suppressor. Set the hole puncher in place, sandwiching the silicone against the polymer cutting board. A couple of good raps with a rubber hammer and the resulting round silicone disk looks factory-made.

Now you place your washer atop the disk and trace out the center hole with a Sharpie marker. Swap out the cutter head with the smallest one in the set and center that in the middle of your drawn circle. A little more attention with the rubber mallet and you’re done. The original SIONICS MAC-10 can accepts two ¼-inch wipes stacked one atop the other.

Anything that touches the bullet in flight is going to adversely affect accuracy. However, this is a .45 ACP open-bolt MAC-10 submachine gun. Does that really matter much? Firing on semi-auto I couldn’t tell any difference in accuracy versus the gun without the suppressor myself. You can just cut a little “X” in the middle with an X-Acto knife in place of the hole, but that is going to tend to add more deflection to your bullets. 

Ruminations on DIY Suppressor Wipes

From my reading, the BATF says it is OK to make your own suppressor wipes at home so long as you don’t stockpile them. In essence, they’d sooner you make them as you need them. Once they’re shot out you are supposed to cut them up with scissors before throwing them away. That’s all pretty ridiculous. I can’t imagine any court in the country, even the crappy ones in places like New York and California, that would prosecute you for possession of unregistered rubber washers. Regardless, if you want to be extra special compliant, just bring your DIY suppressor wipe kit to the range and punch them out on the bench.

American gun laws are indeed pretty darn stupid. However, everything you need to make your own suppressor wipes at home set me back $55, including the little cutting board. Where there is a will, there is always a way.