A person can get some background of this trimmer in this thread: http://www.ar15.com/forums/t_6_42/422021_Frankford_Arsenal_Platinum_Series_Case_Prep_and_Trim_Center.html

However, much of that thread consists of fans reporting how great their (insert brand name here) powered trimmer is and how this "cheap" powered trimmer by Frankford Arsenal must be junk (I paraphrase).
Check out that thread and then come back here if you're still interested in the Frankford Arsenal Power Trimmer https://fsreloading.com/frankford-arsenal-case-prep-and-trim-system-fr-903156.html

My apologies ahead of time for not immediately spending more than $400+ for a powered trimmer, but I'm retired and pennies count, so what I spend my pennies on has to be carefully considered.
At $165 for the Frankford Arsenal Powered Trimmer, the "price" looks good, but I was going to have to get one and see if the "value" was still there after setting it up and using it.

All that out of the way, here's my thoughts on the F.A. Powered Case Prep and Trim System: The Basics, and note that I have broken this up into several posts because I am still limited to 2000 characters per post...

When I unboxed it, I was first impressed by it's weight. There's a lot of metal in that thing, and others have reported already that it's gearbox uses all metal gears. There's not much maintenance to do other than basic cleaning because the gearbox is permanently sealed.
I like permanently sealed, because I've been involved with running lots of equipment during my life, and the pieces of equipment that have seemed to be the most robust and last the longest are those assemblies that are sealed against the tampering of amateurs. So I liked the thing right out of the box. This is not a plastic toy.
Opinions of it looking a bit "Robocop" aside, you can't argue the utilitarian design of spindle placements and the fact that it can be set up to be used in whatever position the operator want's it to be as well as to put any of the chamfering and pocket cutters on any of the spindles you want. You set your own workflow that way.

The gear ratio used makes for a very strong cut, and it's hard to load the motor during a heavy trim that would make it grunt. It doesn't grunt. If you hold onto a case hard enough, it will spin your fingers into a ball and never break a sweat. Be careful that way. (Some exaggeration here.)
On the other hand, I feel that it's a very safe machine because it doesn't spin terribly fast. I put a mark on one of the trimmers and timed it to be running around 120rpm's. That seemed to be plenty fast to do the job, and I felt that the speed it's running gave me very fine control over the chamfering and pocket cleaning operation.

My unit has the "new and improved" outside case trimmer bit. The original outside chamfer bit had a pilot in the middle while the new one does not. The pilot is not missed, and I found that it was easy to get a controlled, small and clean chamfer. If you zoom into the picture of the unit on the F.A. website above, they show the new outside chamfer bit there.

One thing that the F.A. Trimmer has on some of the other high-dollar competitors is that with the F.A. Trimmer, you don't have to buy any other accessories to do additional size cases. This trimmer comes with collets and bushings that allow you to set up for anything from the smallest to the largest bottleneck cases, and changing for case size changes is quite simple once you've done it the first time. Just change out one collet and one bushing, set your length of cut, and go to town.

Speaking of the bits; all four of the rotating shafts are of standard thread sizes, so if you ever wear out the trimmer or any other cutting tool, you don't need to go back to Frankford Arsenal if you don't want to. Just drop by your local reloading shop and pick up a new one.

The pocket cleaner is not what I expected it would be. I thought it was going to be a stiff wire brush, but it's not. It's a solid machined bit with teeth on the bottom, so it won't make the pocket any larger and I found that it really doesn't hit the bottom of a pocket hole. It seems to be the perfect depth for cleaning the pocket TO the bottom, but it doesn't scar up and deepen the bottom of the pocket at all like some of the brush cleaners have been known to do. I wasn't that sure I'd be using the pocket cleaning feature of the F.A Trimmer, but I ended up using it exclusively over any other pocket cleaning tool. As you might imagine, the Trimmer comes with both large and small size pocket cleaner bits.
I should point out here that I do all my swaging on a Dillon 600 and do not depend upon the F.A. pocket bit for getting rid of any crimp. I use the F.A. pocket bit as just a cleaner.

Personally, and keep in mind that this is my personal opinion, I didn't find the multi-steps of "trim, inside chamfer, outside chamfer, clean pocket" to be a big drain on my time. I know that the guys who use the "one step" trimmers swear by them, but for my part, being able to clean the pockets at the same time SAVES time compared with having to do a one-step trim and then have to come back and clean the pockets separately. So I proclaim that to be a wash from the way I see it.
The Frankford Arsenal power trimmer, in that way, compares more to the CTS Pro 600 trimmer which also performs cutting and chamfering in separate operations.

There have been questions about how hot the F.A. Trimmer runs.
I had mine going for over an hour in a pretty warm garage, and after that hour, I put my hand on the housing and it felt just a few degrees warmer than the ambient temp inside the garage.
For perspective, I had a fan keeping me cool during that time, and the housing of that 10" fan motor was a lot warmer than the F.A. Trimmer. The F.A. Trimmer runs quite a bit cooler than I was expecting it to. Hope that helps.

Now to the nitty-gritty of operation...

I went through a half hour or so of frustration when I first put the F.A. Trimmer into operation.
The case would wobble when during the main trim, and it seemed that there was way too much variation of length from case to case. I was getting a spread of between 1.739 to 1.746, and that was NOT acceptable for a trimmer (my target was 1.744 at the time).
Then I figured out what was going on and realized that it was all my fault, so here's the tip for anyone considering this trimmer, but get comfortable, this is going to be wordy.

First of all, I wanted to get rid of the wobble when inserting the case into the length trimmer.
I recall that I saw some guy with a youtube video of the F.A. Power Trimmer who said that he installed a Hornady pilot in his trimmer, and that is certainly one way to make the case center perfectly on the trim cutter. The included trim cutter has a threaded hole on it's side so that you can add a retaining allen screw to hold the pilot in place.
But then I took a closer look at exactly how the F.A. Trimmer works and is set up, and realized that you do NOT want to install a pilot, and that I was simply doing it all wrong.

Here's how the design of the F.A. Power Trimmer works for trimming:
There are 3 Body Collets and 6 Shoulder Bushings included with the machine.
In the case of .223, you want to use the smallest size of both the Collet and the Shoulder Bushing.
The Body Collet is plastic and is composed of fingers that can be adjusted snugger or looser with the outermost chrome nut on the spindle assy.
The Shoulder bushing is designed to rest upon and make direct contact with the correct shoulder area of the case AT THE POINT THAT THE FINISHED TRIM IS ACHIEVED (an important point to know).
What I found that worked best was to adjust the Body Collet so that the case slips in with just a little resistance, enough so that when the cut is begun, the Collet will keep the case from spinning as the cutter comes into contact with the case.

Then here's the big tip and why you don't want a pilot in the cutter:
The slight wobble you feel at first when you come into contact with the cutter occurs because the hole in the Shoulder Bushing where the case neck passes through is slightly larger than the case itself. You feel the wobble because the cutter is cutting the neck, but the beveled surface of the Shoulder Bushing is NOT yet coming into contact with the case UNTIL the case settles into the Shoulder Bushing, and it's at that exact moment that the case IS held perfectly centered with relation to all three contact points; the cutter, the Shoulder Bushing, and the Collet.

I WANT that wobble that I can feel because the moment that the wobble stops, you know that you are at full and correct case trim length.

It is also NOT necessary one bit to rotate the case while trimming or at the end of the trim. The case mouth ends up perfectly planar (side to side) without wearing out your fingers. The only reason you would want or need to spin a case each time would be if the trimmer spindle isn't perfectly aligned with the Collet assembly. If that were the case, then that would indicate a very poorly made product indeed, but I did not find that to be the case with the F.A. machine.

The wobble is from the allowed side to side play at the Shoulder Bushing that happens ONLY until the beveled surface of the Shoulder Bushing comes into contact with the case which happens at the finish of the cut, and that is what sets the alignment of the case to the trimmer.
With that, everything makes sense.

Even if the trimmer bit itself were to be not perfectly planar to itself, the high cutter of the trimmer would be the high cutter all the way around so the end result would still be a perfectly planar case mouth. I'm trying to save people some time by saying that you simply do not need to give the case a spin at the end of the cut.

My technique is to trim each case as if holding a syringe. My thumb pushes in the case against the trimmer while my first and second fingers are behind the back edge of the chrome retaining nut.

Doing it that way, I get a very definitive feel for when the case is trimmed by noticing when there is NO wobble going on and I do not feel ANY vibration of the cutter against the case anymore.

Now to the exciting part; once I figured all that out and made my final adjustment for the cutter, I found that I was getting a case length of 1.748", give or take half a thou, and that, my friend, is very very cool. (I settled upon 1.748" as my intended case length).
I didn't trust me or the machine for a while so I measured each and every case for the first few dozen, but I finally gave up measuring when I was convinced I could trust both the machine and my technique for using it.

One side note I'll toss in is that the trimming process can still put a callus on your thumb after a while.
So what I did was to cut the end of one finger off of one of those heavy rubber gloves that are real "grippy" and slip that one piece on my thumb. With that on, I could process the brass and still be able to use my caliper without taking it off. If you find that the case wants to spin a little when it comes into contact with the cutter, just snug up the Collet nut a little and it will keep it from turning while cutting.

The Frankford Arsenal Powered Trimmer turned out for me to be exactly what I was looking for;  a machine that offers accuracy of trimming, easy chamfering as well as pocket cleaning in one routine, and at a price that won't break the bank.

And now I get to run my 300AAC on the same machine without spending one more dime.

Let me throw in the disclaimer right here that I have no connection with Frankford Arsenal or any other gun related company. I'm just a guy trying to get as much done on a budget as I possibly can. ;)

Have you shortened any 5.56 to 300 black yet? curious on how it worked for that.

Nope, and I really didn't plan on doing so. Trimming that much is a bit of a bite for any trimmer, and it's much easier to just buy the prepped 300AAC cases off of one of the auction sites.

I never thought of trimming as being a cutting operation so I just never gave it much thought.

If I really needed to convert my own 5.56 to 300AAC, I think I'd rig up some kind of mini-chop saw to take off most of the neck and then finish up on the trimmer.
I might play around at some point and do some myself with the F.A. Trimmer for no other reason than that you made me think of it, but I don't think I'd want to sit through a thousand cases at a time.
The F.A. Trimmer certainly has the ummph to do it, but I'm sure it would take longer than I want to spend on it to do it in volume.

Good question, though. I WILL try it in the future sometime just for the hell of it.

I came across the linked thread below, and it looks like I'm in the majority of people who find a more robust way of cutting the cases for 300AAC to be preferable.
Only a couple of people use trimmers (the Dillon 1050 mostly), but you have to buy more parts and I'm not sure it's really worth setting up for it.
You be the judge.
http://beta.ar15.com/archive/topic.html?b=6&f=42&t=358209

Nice job on the review, very thorough!

I leave mine a little tight on the collet to try and avoid the wobble, but I experienced the same thing when first inserting the case. I currently only use the case trim and prep for 5.56, and maybe it was just my prep center, but the cutter head threaded section seemed short. With the cutting head screwed all the way in and the cutting depth set all the way in my cases where always too long. My sleep number is 1.750. I first started with a spring to bring the cutter head out, but settled on cutting a machine screw down. Accurate to .001, usually on the + side. I saw the youtube video as well, maybe starting off with a different cutter head will avoid my problem.

I'm afraid that I don't completely understand what it is that you describe as a "problem".

You say that the cutter head seemed short, but short by what standard? Do you mean that you think that the case had to be inserted too far into the collet?
If so, the further in it goes, the better (short of not being able to grasp the case enough to pull it back out when done), because you want it to be in as much as practical in order to maintain the alignment of the case to the cutter. That is, the further in the case goes, the more surface area of the case being controlled and held by the collet. That's the best way to maintain a straight alignment into the cutting assembly.

You then mention using a spring to bring out the cutter head, and it seems to me that would keep the cutter from being rock solid snug to the shaft which in turn would promote variation in case cut length. The cutter is the most solidly in place when it is screwed all the way into the shaft.

It sounds to me that you wouldn't keep getting a "+" variation on your cut if you would have just a little more patience and hold the case in another half second in order to allow the cutter to do it's work. When properly adjusted, you would get your most dependable case to case length of cut by making SURE that the case is allowed to come to rest on the Shoulder Bushing, and stay there a fraction of a second longer in order to let the cutter finish cutting while the case shoulder is actually resting solidly on the beveled surface of the Shoulder Bushing.
The way to think of it is to imagine holding the case in for a full minute or even a half hour (of course, that would be silly). If you were to do that, the case would achieve it's perfect cut every time because it would cut to the shortest adjusted cut length and not be allowed to cut one bit more no matter how long you held the case in because the Shoulder Bushing is what provides the rock solid rest (stop) for the case.
On the other hand, if you pull the case out a fraction of a second before you give the cutter a chance to do it's minimally adjusted cut, you would routinely get a "+" measurement because you didn't let the cutter finish it's job.

So I'm not really sure what "problem" it is that you are having other than not letting the trimmer work the way it was designed to do.
And as I said and as you yourself sort of complained about, you do NOT need to worry about nor try to stop that initial wobble. It's that wobble, and then the subsequent settling down where the wobble is completely gone, that you know when the cut is complete.
In other words, don't fight the wobble, use it to your advantage as a perfect indicator of when the cut is done by the wobble completely disappearing.
Embrace the wobble. ;)

That's the reason why I spent so much time explaining exactly WHY you get the wobble, and what it MEANS when the wobble disappears.
You see the wobble as a problem while I see it as a very nice feature for what it provides as an indicator of a finished cut (by it's disappearance).

+1