I put up a photo of the 97K on another forum and someone asked if that was a moderator on the end of the barrel. Come to think of it, I don't really know what it is. I discovered the hard way that it is not just a sleeve, after making a pull-through cleaner with heavy fishing line, and losing patches in it.
Just what is that thing on the end of an HW97K barrel?
- Thread starter Billinoregon
- Start date
Muzzle weight, not a moderator.
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.
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.
Last edited:
Upvote 0
Mycapt, I think your experience combined with mine indicates that there is some sort of moderating effect built into the muzzle sleeve. Whether it is an air stripper or some sort of baffle, it would be interesting to find out, but I would prefer not to cross-section mine. 
Upvote 0
You can find out simply by unscrewing the muzzle end cap. If you look at it you'll see a 7mm or 8mm allen key (I forget) fits it perfectly. I never cared enough to unscrew it.Mycapt, I think your experience combined with mine indicates that there is some sort of moderating effect built into the muzzle sleeve. Whether it is an air stripper or some sort of baffle, it would be interesting to find out, but I would prefer not to cross-section mine.
View attachment 352042
Upvote 0
Moderator for/on my HW95L. I use it for a cocking aid & I remove it when I pull through cleaning patches tied on a length of mono.
Upvote 0
It's a completely empty cavity. There are different kits that can be inserted into that area. HW makes their own mod that will thread directly into the threads once the end cap is removed but it does not go into the cavity beyond a few threads. There is NO doubt the end cap does quiet the report by a fair a bit. If you want, fire the 97 with no end cap and compare it to when it is installed. I have fired my 97 with and without end cap, there is a BIG difference, but the cavity is empty from the factory (at least on US models).
Last edited:
Upvote 0
Yep. I just looked in mine. Completely empty. Somehow it still quiets the report noticeably
Upvote 0
A single expansion chamber can make a big difference in report for sure. I added a 3d printer empty chamber type ldc to my evanix rex .357 and it went from so loud I needed ear protection to quiet enough to shoot without protection.
Upvote 0
It also has a set screw underneath that holds it. Mine came loose once and accuracy degraded.
Upvote 0
I bored mine out and pushed the barrel further up. This reduced the overall length of the gun by almost 3” without having to shorten the barrel
Upvote 0
Did it change the accuracy? And you had to shorten the cocking arm, harder to cock now?I bored mine out and pushed the barrel further up. This reduced the overall length of the gun by almost 3” without having to shorten the barrel
Upvote 0
Hello there! Are those the pellets you recommend for the 97? I’ve just ordered this gun and hoping to save some $s on testing brands. Thanks for any comments.Mycapt, I think your experience combined with mine indicates that there is some sort of moderating effect built into the muzzle sleeve. Whether it is an air stripper or some sort of baffle, it would be interesting to find out, but I would prefer not to cross-section mine.
View attachment 352042
Upvote 0
I'm not the original poster, but I have a 97K. Mine will shoot several pretty good, but the best accuracy I've got out of it, is with the QYS 8.48 domed, JSB Exact 8.44, also Air Arms 8.44.Hello there! Are those the pellets you recommend for the 97? I’ve just ordered this gun and hoping to save some $s on testing brands. Thanks for any comments.
It kinda depends on how the pellet fits your particular bore. You want a semi snug fit, and you can tell when you insert it into the barrel. Generally speaking, loose fitting pellets don't group as well and often will be flyers. Back when I first got mine all I ever shot was JSB Exact 8.44 and they were great. As the years went by I tried many others until I found the QYS 8.48 domed would out shoot the JSB's 8.44. But like I say, it will depend on your particular barrel.
Upvote 0
Upvote 0