So I've on fired roughly 300rd through my Silencerco/SWR Octane9 HD2, all with a fixed barrel adapter on my CZ Scorpion Evo3 SBR. I just got a threaded barrel for my M&P9 so I installed the piston, spring, and std base cap but noticed that the piston way VERY difficult to install. I couldn't just drop it in, I had to tap it in with a small nylon mallet. I pulled it out and inspected the non-removable bird cage area and noticed a little bit of carbon build up. After a lot of cleaning I finally got the piston to drop in 95%, just had to push on it at one point.

My concern is that I plan to primarily shoot this on my Scorpion, but it seems like with the fixed barrel adapter the bird cage area is the blast chamber and will be subjected to a lot of carbon build up. Clearly it only takes a couple hundred rounds before I can't install the piston, so going between hosts is going to be a PITA.

First, am I correct in believing this is an issue, that the piston must drop in freely? Is there any trick to swapping between fixed adapter and booster setup with relative ease? Is there any kind of sleeve I can put in the bird cage area to protect it from carbon build up (similar to using a fixed barrel spacer)?

 
This. Another solution is to get another Octane.


One of mine is dedicated to fixed and 3-lug mounts and the other for pistons.

Thanks. The only issue with that is my Scorpion is an early one with that odd ball metric threading, no pistons available afaik.

SiCo has an 18x1 fixed barrel adapter for the Octane/Omega line.

Yes, that's what I'm using and that is the problem. When using the threaded adapter, the bird cage area is subjected to carbon build up. If using a piston and fixed barrel spacer, the spacer protects the bird cage.

FYI, a 1" pipe cleaning brush like this will help clean out the blast chamber:

https://www.amazon.com/gp/product/B0161B70XG/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

Ahhh, and I was just at Lowes....

I decided to try a thin metal sleeve in the blast chamber while using the 18x1 fixed barrel adapter. I wanted to use stainless but couldn't find anything of the correct size. Ideally I wanted something with an OD of 0.99" but that proved difficult. I did find a 3/4" copper coupler 0.965" OD that I cut down to 1.15", only $0.90 from Lowes and took 5min. Going to the range tomorrow so we'll see how well it works.

FYI for anyone else thinking about this or who may find this searching in the future, the length needed is different with the 18x1 adapter vs the standard booster cap. If using the booster cap and making a fixed barrel spacer it would have to be more like 1.25" 'ish.

Tag for later.