Supposedly theres a small plastic baffle in there. Whether that's true or not, I can't tell you. I can tell you it definitely reduces noise. I found this out by stupidity.
I use a pull through system to clean my 97s barrel. I put a 3" piece of fat soda straw in the end of the muzzle so the pull through doesn't get hung up. When I shot it after cleaning the barrel it was so loud I thought I dry fired it. Mind you I'm doing this in an cement 10 yd basement range so sound differences are exaggerated. Seeing a pellet hole in the target I knew I didn't dry fire it so I thought some residual cleaner detonated.
I fired it again figuring the barrel was cleared out on the last shot. It was still very loud. WTF?
I figured I'd dry patch the barrel again to be sure I got all the solvent out. That's when I found the straw was still in the muzzle device. DUH!
I removed the straw and the gun was right back to its normal quiet self. I put the straw back in to be sure it wasn't coincidence. Low and behold it was loud again.
Bottom line, whatever that thing on the end is, it does something. At least on my gun. I bought my gun new and have never taken the end cap off the muzzle. The fat straw defeats the device and you can easily test this for yourself.
View attachment 352023
