I was surfing the web and I stumbled across this picture. On that MP5, mounted to the lugs on the barrel, is a “Solvent Trap” with an oil filter on it.
I forgot those things existed. I’m pretty sure I posted about them not long ago.
When we clean a gun, pushing or pulling a brush with solvent on it will result in the brush spraying some of that solvent and crud around when it exit the bore. (What I usually do is forget about this fact of nature, and run a solvent soaked brush though a bore while I’m wearing a good shirt standing next to white drywall) I am reminded of a particular annoying bench rest shooter at the range I used to work at would clean his rifle after every match. He would use a jag, push a patch through the bore and let that dirty patch fall to the ground to get blown away by the wind. After a match, after he cleaned his rifle, there would be a good 30-50 plus patches blowing around the range. Had it been up to me, I would have banned him from the club over intentionally making a mess each weekend.
Someone came up with the idea of selling a clear plastic tube with plastic end caps you could slide over the muzzle of your rifle. That way, when you were running a brush or pushing patches all the trash and splatter would be contained in the easily cleanable clear tube.
Tipton sells something similar that uses a soda bottle.
Now, I don’t know what came first. Someone realized you could use an oil filter as a cheap silencer. Someone realized you could use an oil filter as a “solvent trap”.
For example, Cadiz Gun Works sells Oil Filter Silencers for $85. Now, since the oil filter is part of the silencer, when you want to replace it, you need to ship this silencer back to the manufacturer, CadizGunWorks, who will replace the filter and charge your $25.
As for the oil filter “solvent traps” since they are a cleaning tool, and perfectly legal as is, you can buy one and have it shipped to your door.
For example, Infinite Product Solutions, sells a “Three Stage Adapter” with three different thread sizes so you can mount an assorted variety of various filters or mufflers to function as a “solvent trap”.
There is an ATF letter floating around talking about this:
ATF letters only apply to whom ever asked the ATF the question. But if you fall into the same situation, you will likely get the same result. Not always. This letter states that if you or I decided to use a Form 1 and turn an adapter into an oil filter silencer we would not be allowed to swap out the oil filter with out submitting a new tax stamp.
So if you are thinking about registering an oil suppressor, it might be a poor value for the cost.
I imagine that in a SHTF type situation, items like oil filter silencers might be a little more popular.
Might not want to use them on larger calibers or weapons you plan to do higher volumes of fire. Many of these filters use a fibrous medium that might catch fire if overheated.
People have been arrested and prosecuted for using illegal oil filter silencers. Here is one example: https://www.guntrustlawyer.com/maryland-man-arrested-fuel-filter-silencer/
At this point I’ve rambled for a while, and I’m not sure if I ever had a point. But here is a fun aside:
Maverick Precision sells “Solvent Trap Filter Media“
These “Mil-spec filter media designed to catch carbon & other contaminates” are sold $50 for a pack of 10.
I think those look familiar. Look at the 3 slits cut in each round patch. Like cleaning patches…
Now look at those round patches with 3 slits cut into them. These Otis patches are sold for $7.49 for 100.
I’m sure that Maverick Precision would never take a 7.5 cent cleaning patch and sell it for $5. Right?