"Solvent Traps", Still VERY ILLEGAL to Use As Intended

Steve Johnson
by Steve Johnson

I regularly get emails from people asking me to tell them how to do something illegal. Often these people phrase the questions they ask in such a way as to trick me into telling them how to break the law. Today someone told me his friends and him were having a debate whether or not a .300 BLK round could be suppressed with a oil filter, and if so, which would be the best brand to use … I was not born yesterday. I am not going to tell you what brand of oil filter to use to illegally suppress a rifle.

For those of you who are not aware, a couple of years ago the concept of using a automobile oil filter as a suppressor spread across the internet like wildfire. One company began making cheap $70 adapters that were legally registered as suppressors. Other people committed felonies by using simple cheap thread adapters to make illegal suppressors. These adapters are now sold as “Solvent Traps” or “Solvent Catchers” … like you cannot use any random metal or glass container (or just a dirty rag) to catch solvents poured down a barrel.

An oil filter, very suppressor like.

I thought the oil filter craze was long dead and retailers had stopped selling them. After achieving the above mentioned email, I did a Google and found the trade in them is alive and well. One eBay merchant is selling around 1,000 simple thread adapters each year for just $9 (including shipping!). He also sells a range of adapters for popular unthreaded rimfire rifles. They are sold as “Solvent Traps”.

Using these, or being caught with an adapter, a threaded rifle and a oil filter could land you in Federal prison. In 2012 a man was sentenced to 2 years in a Federal penitentiary for illegal possession of a homemade suppressor.

Yes, the law is ludicrous, I am not defending the law. That a simple thread adapter can be illegal to use on a rifle, but a muffler can be used on a car makes no sense. But regardless, spending a couple of years in prison and never being able to own or buy guns and ammunition again, is far too steep a penalty to justify the risk. Suppressors are fun, but they are not that much fun. Trust me, I own many suppressors. Save up and buy one legally. In the day of camera phones, all it takes is for one friend or neighbor to photograph/video you using or making an illegal suppressor and you can then kiss all your guns, and your freedom, goodbye.

Steve Johnson
Steve Johnson

I founded TFB in 2007 and over 10 years worked tirelessly, with the help of my team, to build it up into the largest gun blog online. I retired as Editor in Chief in 2017. During my decade at TFB I was fortunate to work with the most amazing talented writers and genuinely good people!

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  • Secundius Secundius on Oct 30, 2014

    The Solvent Trap 1/2-28" to 13/16-16", can also be used as a Thread Reducer or Ncreacer, too.

  • John Smith John Smith on Nov 11, 2014

    Roberts was charged with 228 counts of illegal activities. Including illegal possession of stolen things, possession of drug paraphernalia,
    hunting with an illegal firearm, hunting deer with illegal methods,
    hunting and taking deer during illegal hours, hunting from a public
    road, possession of untagged deer, failing to maintain sex identification of
    deer, failing to tag deer and possession of illegally taken deer.