There is much discussion on the internet. Mostly using tires with different foam and fillers for more noise reduction. I don't remember it but the internet says Ken Waters built a range silencer and wrote about it for Wolfe. I'd talk to an attorney in the local jurisdiction before I put money into getting around the law. Here is a bit from the internet.

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There used to be plans for this exact thing in Shooting Times magazine and it was called a gun muffler. I have a set of the plans and they are copyrighted by Rick Jamison, 1993. He used barrels welded together and packed with tires. The tires were filled with metal machining chips (curly q's) and held in place by a coarse mesh. The chips were used as they were non-flammable. There was a hole in the bottom so you could wash out the unburnt powder that collected inside. I never did build it because there was a lot of discussion about whether or not it was legal in my state (Kansas). I had collected some barrels that had the tops held on with clamps and figured I could clamp the barrels together and still get them apart for cleaning if it became necessary. ARFCom

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frank505
04-24-2007, 10:27 AM
I made the box from the article in Handloader Digest. the "plans" were wrong so we improvised. It did work well, turned a rifle shot into a high pitched crack that was not very loud and did not carry far. The range was across the creek and 80 acres from the houses and barns, but was almost unnoticable when you were working. It ends up being very heavy and full of wasps unless you make doors for both ends. My range was anything up to 300 yards, just pull the bench with a four wheeler to where you wanted to shoot from. The sound box was built on skids also but it is rotting away since we sold the place. I think the tires in ascending and then descending sizes would do the same thing and much easier and cheaper to build. The idea of holes in the bottom is a great one, tires on fire are hard to put out!!!! It is ok to shoot from the bench for load testing but better yet build some loads and shoot away from the damn bench. I have yet to see a bench in the hills of Wyo when hunting.