Residual material and 3D-printed suppressors

Ape_Factory

Major Hide Member
Full Member
Minuteman
  • May 23, 2020
    1,532
    1,087
    San Antonio, Texas
    It was my turn to get bitten by residual titanium dust syndrome. I was at the range dialing two new scopes and doing a few ladder tests and I had a major failure to function on my first test round. I'd shot about 20 rounds prior dialing in the scopes. The FTF round fired just fine but the case stayed put in the chamber. I've never had that happen in any of my rifles ever. It was a 169 grain projectile which registered at 2490fps out of a 16" barrel so not anywhere close to being hot.

    Getting the rifle home, I used an alignment rod and pushed the case out. Came out very, very easily, literally no effort. 1/3 of the rim was gone, ripped off and the primer was sucked in (cratered in but not like we normally think of cratering of the primer) which I've never seen either.

    The BCG was pretty dirty as it'd been a bit since I cleaned it. The last time I pulled it, I'd noticed a bit more wear on the surface coating so I lubed it up a bit more. Pulling it this time, I noticed that the gunk felt like emery paste, like a really fine grit. After cleaning off the carrier, the accelerated wear was obvious. I had at least 4K rounds on the BCG with limited wear marks prior to switching over to, you guessed it, a new titanium 3-D printed can.

    I cleaned off the carrier and bolt and my carrier definitely showed a significant amount of wear from about 500 rounds with the new suppressor. I don't think it's toast but I'll probably purchase another here soon. The bolt is new and didn't show any wear.

    I cleaned the sh*t out of the BCG and upper receiver, barrel extension as well as the barrel. The barrel looks ok to me but I had been having issues dialing in hand loads lately but thought it came down to LC brass from different years.

    I took the suppressor, plugged the end, and filled it with CLR. I let that sit for a bit and dumped it out. I then dropped the suppressor into an ultrasonic cleaner filled with nothing but water and ran it for an hour. A LOT of crap came out including residual titanium material. It feels different from carbon so it's obvious. I have another suppressor, same manufacturer, made with inconel and out of an abundance of caution, I cleaned it in the ultrasonic with M-Pro 7. The BCG in that rifle looked fine although I noticed a bit of wear on the underside where it interfaces with the trigger hammer. On the other rifle, that area was polished to an almost mirror-like finish.

    I'd suggest anyone purchasing a similar suppressor in titanium, no matter who makes it, flush it out, clean it in an ultrasonic cleaner and otherwise be quite aggressive in trying to remove any residual material. Clean it, shoot a few rounds, and clean it again.

    I'm hoping I dodged a bullet. The upper receiver looked ok as did the barrel but I realize I may need to purchase a new barrel along with a carrier sooner than later. I'm going to reach out to the manufacturer but I'm sure they'll tell me to pound dirt. And no, it wasn't CGS.

    On the caved in primer, I know the case headspace was set correctly. Like no question. I measured each at least three times before loading them up. None of the previous 20+ rounds had issues. I do know initially the chamber was on the tight side as it'd be a bit hard to extract a loaded round. Fired rounds were always ejected until the aforementioned round with the broken rim.

    A few pics of the carrier and case.












    One thing I did notice, is the dimple in the primer looks slight off center. Those are factory-loaded Winchester rounds. The swipe marks on the center case are "normal" for my rifle. The one on the left shows none as it's completely random when it happens but it happens more frequently than not.
     
    I cleaned every nook and cranny thoroughly, upper, lower, trigger group, you name it. Lubed the rifle up and went out and shot this weekend. No more FTF's and I had to turn the gas down a bit. Barrel shot well too so sigh of relief a new barrel isn't going to be an immediate requirement.

    And just to clarify, I did do an initial flush of the new suppressors but simply ran water through them, shook, etc. Wasn't enough obviously and I think their hybrid baffle design is one of the reasons why as it's easy to trap water or other material in between the baffles. The only 3D printed cans I've not had do this are Huxwrx. I've never flushed them out and never had a problem with residual material out of their cans.
     
    I always wash my cans with dawn and hot water to remove any dust or oil from manufacturing as well as degreasing the threads for my mount. So, I haven't had this happen but it (i think) makes sense and sorry you had to experience this.
     
    Any of the 3D printed cans. I just got in a Huxwrx Flow 9Ti, forgot to clean it first and it was like 4th of July for the first magazine. Second mag was all good. Hand gun and I haven't checked it yet for residual debris but probably should.

    Which can did you use specifically that you posted about in your post?
     
    It's called reversion. Known principle that's best known in the automotive industry where gasses can get sucked back into the combustion chamber under vacuum after a volume of hot gas that's consuming air passes through a tube.
    I was being sarcastic, based mostly on the BCG pictures. That kind of wear doesn’t happen in 20 shots even with a BCG literally covered in lapping compound. If you’ve ever lapped bolt lugs on a bolt gun you’ll get my point here; it takes hundreds and hundreds of motions to remove nitride or coatings and polish up lug surfaces.

    I’m just skeptical that titanium sintering residue could ever cause that in 20 rounds. I’m not saying you’re nuts, just that a 4000 round BCG probably has that kind of wear normally without any fancy coatings. Back pressure coming back down the tube has little actual flow or pressure so I wonder if weighted material could really be floated in this way much beyond the muzzle.

    Just my personal opinion on the pictures. Nothing more.
     
    • Like
    Reactions: Obi-WanKannoli
    Yeah no worries, I get your skepticism if not the sarcasm, LOL. I can truly say it did not look like that the last time it was cleaned and you could visibly see and feel the titanium dust/grit on everything internally after pulling the BCG out. I keep that rifle fairly clean for the most part, usually after every other range session so I'm very familiar with the internals and I probably over lube everything so that wasn't the issue. This time it was multiple range sessions in between cleaning (I always add a bit of lube without taking the BCG out and this wasn't the first time I'd been using the LS3. I just kept it on the gun and didn't clean anything in the meantime. So it wasn't 20 rounds it was more like 500 rounds suppressed. It was 20 rounds into the session that day before I had the case get stuck.

    I'd probably share your opinion if I hadn't experienced it first-hand and being very familiar with the condition of the components, I am not in any doubt the contamination from residual titanium dust is the culprit. And the fact the case jammed, something I've never experienced with that rifle or any other for that matter, was just another big indicator something wasn't quite right. I just didn't notice it until I went and pulled the BCG.

    But yes, a lot of that wear is from normal use. What isn't are the lighter spots where the coating is gone. I know it's a bit hard to tell as it's just an iPhone photo but you can see where there's normal wear (medium to dark gray in color) and the whiter areas are where the increased wear is. So if you look at some of the sharper edges as well as the underside of the BCG and the top around the gas key, those areas had a bit of wear but after, the coating was pretty much completely worn off and in places which previously showed no wear ( the "flats" behind the top leading edges of the bolt carrier).
     
    • Like
    Reactions: Obi-WanKannoli
    I’m going to do this to my HUXWRX tonight when I get home. There have been too many similar complaints brought up about this. Seems like it will either be beneficial in preventing unwanted wear or a waste of 10 minutes. I’ve got 10 minutes to spare. Thanks OP. I’ve got a couple hundred rounds through mine, but it’s been spread out over at least 4 rifles I believe. Should I still do this?
    Do you think this relates only to Ti printed cans or should any printed can be washed out like this? I’ve got 2 Velos LBP that should be approved in the next day or 2.