I finally finished my suppressor build this last week, after several frustrating issues printing with PA6-CF. The first attempt went admirably until about 30 hours into the print when a pop up lightning storm cycled the power with just a few hours to go. I didn't have enough filament left on the roll to try again, so I ordered another roll of filament. When it came in, and I went to dry it in the food dehydrator I'd ordered just for this purpose the screen just blinked on and off. After a bit of investigation, I was unable to find any blown fuses or anything obvious wrong with it, so I tried drying the new roll in the oven. The oven clearly didn't keep a proper temperature, because my subsequent print had some spots where it had moisture in it, and was too warped to line up with the bore. Eventually, I was able to get a decent print that seems like it will work.
While the core is printed, it has an aluminum tube that reinforces the Z axis and keeps everything from blowing apart. JB Weld is used to bond the tube to the core. A Breek Castle Shield is pinned into the printed core with hardened steel rods to allow it to thread onto the flash suppressor without blowing out. The aluminum tube holds it all together.
This is my deer rifle when I'm not fooling around with my flintlock, and I still haven't had a chance to test it out and zero the rifle with the new suppressor. Im working this weekend, but hopefully I'll get a chance to check everything out on Monday when I am off. Until everything checks out I guess I'm going to be hunting with the front stuffer. Anyhow, here is the Pic, it's a .300 BLK rifle with a 10.5 barrel (amnesty braced lower) plus the FTN.4 suppressor.
Everything was properly Form 1'd through the ATF for this build and the approval took just over one business day. With the tax for a Form 1 suppressor going from $200 to $0 on January 1st, I can see this being a viable alternative to commercial suppressors if everything works out as it should.