Oh I'd like to write a few pages but I don't have the time. I bought a FD 308 with a 16" barrel at the end of last year. I read every word of their marketing and manual. I was really sold on the gas system and the "infinite adjustability" it supposedly had since I planned on running a TBAC Ultra7 most of the time. I'm really fussy about precision machining so their marketing on their website caught me hook line and sinker.
First thing when I got it I went to cleaning and inspecting just to get familiar with it. My Sinclair bore guide wouldn't fit in the upper. The bore is substantially smaller so I'm guessing they are running a proprietary bolt carrier size. I haven't looked into that one further but I have a feeling they manufactured a lot of the parts a little off standard so you are stuck with them.
Next thing I found I couldn't pull the bolt all the way back to lock with an empty mag in it. LONG story short, the bolt catch was moving up behind the bolt lug and stopping it dead since there wasn't enough angle on the catch - or - it was machined so that it reached an improper position. Their advice was to yank the bolt back harder and/or just shoot it till it breaks in. Well no way in hell I was doing that since I knew this wasn't right and could likely hurt something. I bought a Seekins bolt catch to replace. Wouldn't fit. The slot in the receiver is machined about .010 too small. The Seekins along with other brands I had around all had ramp angles that wouldn't allow this problem to happen. So I remachined the angles on the FD catch and all was fixed there. Silky smooth like you would expect.
As I'm fiddling with this catch and bolt, I see the bolt carrier has tiny little dings all over it. I recognize it as being caused by a tumble deburr operation where too many parts were loaded into the tumbler and all the bolts beat against each other. FD's official response was they are aware of it but most people don't notice it. A subcontractor handled them rough and they couldn't just scrap the batch because of it.
Next, the bolt has areas that are very rough with a pitted like appearance. Particularly so on the lower half of the bolt face. I recognize this as being caused by lack of controls during the heat treat process. No official response from FD on that one. It might have fell in the same category as the bolt carrier.
On to changing the muzzle brake to the TBAC unit. It didn't just break free. It took a good turn before it freed up. After getting it off I saw why. The threads weren't machined far enough in their brake so when they torqued it home it peened the fist thread over on the barrel and now has a sharp burr protruding forward of the crown. UGH!!! You've got to be kidding me! FD's response - complete denial. Just not possible. Must be carbon or something.
So I get everything in good working order and proceed to working up a load. Starting off light and working up. I've got the suppressor on and I figured I'd set the gas to "OFF" till I got it shooting, then work with tuning the gas system. To my surprise, the bolt cycles and locks back in the off position. Every time! (I've got to jump over all the investigating. No time for it now). Summary: The adjustment needle is not machined to seal off the gas when bottomed. When bottomed there is still a large opening at least on the largest gas port position. There are gas sealing rings on each side of the gas ports. The largest of the gas holes, "HIGH" setting, was machined breaking into the gas ring groove so when it's in the "OFF" position where there is no gas hole at all, the gas just travels around the ring groove and through the big hole and cycles the bolt. FD's official response - just shoot it - then crickets.
I've got lots of pics to prove what I'm saying if needed. There are a lot of things that impressed me too. It's a damn shame because I think this design has a lot of potential.
