AirMaks Arms Katran LB rattle

[IKnowNutin]

My "new to me" Katran LB .25 has a very noticeable rattle when handling it. There is a small gap between the outer diameter of the barrel and the inner diameter of the fluted shroud. That is what is causing the rattle when tapped gently. Is this by design or am I missing a bushing or something? I've attempted to attach a video that shows what I'm talking about Thanks.

 

[MACTEN]

My "new to me" Katran LB .25 has a very noticeable rattle when handling it. There is a small gap between the outer diameter of the barrel and the inner diameter of the fluted shroud. That is what is causing the rattle when tapped gently. Is this by design or am I missing a bushing or something? I've attempted to attach a video that shows what I'm talking about Thanks.

View attachment 425128

I'll have my buddy see if his does this today who lives near me. Unless someone else chimes in.

 

[weevil]

It’s clear from the photo that the air stripper collar around the barrel is broken up and needs replacing.

 

[IKnowNutin]

It’s clear from the photo that the air stripper collar around the barrel is broken up and needs replacing.

It would be great to see what the collar is supposed to look like. Airmaks's parts documents don't break it down that far and actually start at item #62 in the list. I'm using Airmaks's universal moderator.

 

[weevil]

It doesn’t look bad from that angle. My Katran SC has the same look. The cloverleaf allows air to vent back into the shroud. Does it still rattle with the moderator section removed? The whole shroud twists on and off, so perhaps it is loose?

 

[IKnowNutin]

There is an equal gap of a few thousandths (not measured , just eyeballing) between the shroud and barrel. ....so the barrel is floating from the receiver outward and only contacts the shroud clover leaf area when gently tapping the shroud. I've removed/installed the shroud. It is secure against the receiver. Everything seems normal to me except that it rattles, which I have a hard time believing to be normal. Also, it does it without the mod and air stripper installed as well. I thought the extra weight on that long arm might contribute to the contact but it doesn't change a thing. Hmmmm

 

[weevil]

Mine has the UNF collar firmly affixed to the shroud so it’s difficult to see inside. However, there is no movement between the stripper and the barrel. It seems very unlikely that they would have metal to metal contact supporting that union so perhaps there should be a thin plastic bushing. Airmaks is very responsive to email.

 

[IKnowNutin]

Mine has the UNF collar firmly affixed to the shroud so it’s difficult to see inside. However, there is no movement between the stripper and the barrel. It seems very unlikely that they would have metal to metal contact supporting that union so perhaps there should be a thin plastic bushing. Airmaks is very responsive to email.

Thanks, Weevil. I was just thinking perhaps a little bit of PTFE tape might work to keep metal off metal. I'll shoot AirMaks an email.

Also, on another note, I appreciate your time and effort working out the Caiman X regulator issue. I intend to perform that fix on mine in the near future