SILENCER SATURDAY #217: Replacing Silencer Wipes – B&T USA STATION SIX9

There is a common misconception surrounding wipes that implies that wiped silencers needs to be sent back to the factory for replacements every 20 rounds. While it’s true that the ATF has stated that manufacturers can not sell wipes directly to consumers, replacing them isn’t a huge deal. Manufacturers can send replacement wipes to FFL dealers which can then replace customers worn out baffles. Or, with a bit of research and caution, you can make your own replacement wipes. However, you may not have spares on hand – there needs to be a one-for-one swap for new and old wipes

The disassembly kit includes a push rod to remove the wipes and spacers, but mine slipped out easily. The above images show the SIX9 wipes after 3D rounds, starting with the one closest to the barrel at the bottom. I expected more deformation, especially in the last two wipes.

The wipes sit inside a slight ledge formed into each spacer. The entire maintenance took about 5 minutes – wiping down the tube and spacers, replacing the wipes, and dropping everything back into the tube. Again, replacement wipes can be purchased from B&T USA and sent to your local FFL.

Note: The following information is for informational purposes only. Follow the manufacturer’s guidelines for wipe replacement with factory materials. Damage to your suppressor and/or serious injury can occur with improper parts and installation.

If you want to avoid the hassle of ordering and shipping four small silicone discs to your dealer, the ATF has stated that owners may make their own wipes. By law, you are not allowed to possess spare suppressor parts so you are not allowed to make 100’s wipes, only enough to replace the damaged ones. The whole thing is ridiculous – being given permission to make rubber discs – but these are our laws.

Wipes can be made from neoprene, Polyurethane/Urethane, silicone and other flexible materials. The goal is to squeeze the bullet through several layers of rubber, trapping expanding gas an noise between the layers. Wipe material is categorized by the Shore hardness on the durometer scale.

What is the durometer scale & Shore hardness?

The durometer scale measures the Shore hardness of rubber, plastics, silicone, and other polymers and elastomers. There are multiple durometer scales that measure the resistance of indentation for a variety of materials, with the most common scales being the Shore 00 Scale, Shore A Scale, and Shore D Scale (credit: AeroMarineProducts.com).

For suppressor wipe materials, we’ll be using the Shore A Scale:

The Shore A scale measures the hardness and flexibility of a wide range of materials, from very soft mold rubbers to semi-rigid plastics. Examples of items that are measured using the Shore A scale include soft items like rubber bands to more rigid objects like shoe heels on dress shoes. The Shore A scale indenter has a spring force of 822 g (credit: AeroMarineProducts.com).

My friends at Hanson Brothers (FFL/SOT Dealer) put together a list of wipe materials, durometer scale ratings, and the size/thickness of some common silencers that require replaceable wipes, over at AR15.com. It appears that most wipes fall between 25A and 80A on the Shore scale. For reference, that is somewhere between rubber bands and leather.

Sheets of neoprene, Polyurethane/Urethane, silicone can be purchased on Amazon in varying thicknesses. An arch punch is used to make clean cuts with precise measurements. Just place the punch on the material, laying on a plastic cutting board and hit it with a hammer. Hit the punch, not your hand. The result us a perfect circle of silicone. Use a sharp Exacto blade to make the X-cuts.

I’ve included links to some suggested tools and materials below.