Vuurwapen Blog
27Mar/100

Mike Pannone Tests the Bravo Company Upper Receiver Group

Posted by Andrew Tuohy

I know of no one who personally puts more rounds down the barrel of AR-15/M4 type weapons each year than Mike Pannone. I've had the honor of shooting with him several times, and came away from those brief sessions a better shooter. I greatly respect his opinion and experience on all things AR-15/M4.

He's recently completed an exhaustive test of a Bravo Company 14.5" M4 type upper receiver assembly. You can read the details here. In essence, he stripped away all lubrication, replaced critical items in the lower receiver, and proceeded to shoot 2400 rounds through the weapon with only magazine-related failures (he used USGI type mags to simulate as closely as possible the military M4).

26Mar/102

POF R.D.I.K.

Posted by Andrew Tuohy

After my tour of the POF facility yesterday, I was temporarily loaned two POF upper receiver assemblies, one of which is photographed below.
The upper assembly has a 16" fluted barrel with a carbine length gas system. It is built around the reinforced POF upper receiver and uses the POF modular rail system, which is equivalent to a 9" free float rail in terms of length.
It's remarkably light and well balanced - this rifle would have a neutral center of gravity with a lighter stock. For those of you who are not familiar with how I define various centers of gravity, and why this is important, click here. (Parts 2 and 3 are coming very soon, I promise).
It has a two position adjustable gas block - "normal" and "suppressed."
The large barrel nut functions as a heat sink, shedding heat rapidly.
The gas key has been clearanced to allow for installation of the POF Roller Cam Pin....wait a second...the gas key?
That's right, this upper has a gas tube, not an op rod!
This upper retains all the features of the POF P-415 uppers, with the important exception that it functions much like a standard AR-15. There are important differences - the gas tube is of a different design, is held in place using a dowel pin instead of a roll pin, and, of course, the gas plug regulates how much gas gets back into the action. Hence the name - Regulated Direct Impingement Kit. I'm told that it may be offered in various forms. As this is a prototype, details may change. I'll be comparing this upper to a POF op rod upper as well as standard AR-15s in the next few days.
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26Mar/108

Inside POF-USA

Posted by Andrew Tuohy

Recently, I contacted Frank DeSomma of Patriot Ordnance Factory with a request for a T&E upper to be used for an upcoming SPR comparison.

Noting that I was in Arizona, Frank invited me to take a tour of POF's facility before I tested one of their uppers. It should go without saying that this was an offer I couldn't refuse.

Located in an industrial park devoid of any indication that a world class manufacturing facility lurks within, POF is composed of a machine shop - two machine shops, really - an assembly area, a shipping area, and a small front office. I was impressed when I saw that no employee seemed to be idle for more than a few moments during the entirety of my visit, which lasted nearly 3 hours. Everyone was doing something, and they all seemed to be doing that "something" in a very efficient manner.

Frank spent a good deal of time explaining the function of various components of the POF system. I'll cover those as best I can, but I may revise details over the next few days if I find that I misquoted him or made a technical error. I'll also probably expand on certain items in the next few days, but I have a lot of ground to cover here, so the initial post won't be as detailed as I'd prefer.

Frank came from the aerospace industry, and he had certain objectives when he set out to design his new system. His first objective was heat dissipation. To that end, every POF rifle and upper has a fluted barrel and an aluminum heat sink barrel nut - aluminum because it dissipates heat 5 times faster than steel. Even the shortest POF barrels are fluted, he said, because he doesn't believe in cutting corners.

On the left is a 5.56mm barrel nut. On the right is a .308 barrel nut.
Fluted barrels on POF short barrel uppers.

Frank gave me a lot of impressive figures about heat dissipation after big round counts. I can't remember them exactly (I should have been writing this stuff down). He did tell me something very interesting that I can remember, though - although he uses standard bolts in his 5.56 firearms, he's never had a broken or cracked bolt come back for repair/replacement, nor has he had one break in his own testing.

I also was shown cutaways of upper receivers, both standard M4 and POF. I'm familiar with the phenomenon of receiver flex - when forces are exerted on a long handguard, especially with a vertical grip installed, the forward portion of the standard M4 receiver can deflect by a very small amount. This deflection, however, can cause premature wear and failure of bolts. To this end, companies such as Vltor have designed the MUR and VIS, LaRue Tactical has designed the Stealth as well as the OBR, and POF has designed its own upper receiver, seen below in cutout form next to a standard M4 receiver. Although they're facing away from one another, note how thin the top of the M4 receiver is compared to the POF upper.

Comparison of POF and M4 upper receivers.
Not only is the receiver thicker, but the barrel is supported, for lack of a better term, by the massive barrel nut.

After this "system overview", I was shown some new POF products - a 7.62x39 SBR was among them. Here, from the top, are 6.8, 7.62x51, and 7.62x39 POF SBRs.

More shots.

There were additional items discussed at that time, but I'll cut ahead to the manufacturing portion and cover those later.

Frank is very proud -  as well he should be - that he manufactures most of the components for the P-415 and P-308 in house. We'll start with receivers.

Each P-308 lower receiver starts as a 7 pound "billet" of 7075-T6 aluminum. By the time the lower receiver is finished, 6 1/4 pounds have been whittled away. P-415 lower receivers start and end at a reduced percentages of those weights.

This CNC milling machine is where lower receivers take shape.

Magazine wells are wire EDM cut to precise tolerances - .0001 - that's one ten-thousandth of an inch.

Wire EDM machine
These are the unused magwell portions.
P-308 lowers waiting for the EDM process.

Upper receivers come to life in two different buildings, but for the sake of organization, I'll describe it all at the same time.

5.56/6.8mm uppers start as 7075-T6 forgings. Note that multiple parts are being machined at one time - production was being maximized whenever possible.

Upper forgings are prepared for machining.
Inside this big machine, midgets with chainsaws carve POF upper receivers.
P-415 upper receiver forgings being machined.
POF P-308 upper receivers start as large aluminum rounds.
Bolt carrier "blank" compared with machined bolt carrier.
P-308 bolt carrier being machined
Birth of a POF rail/handguard system.
Disconnectors are wire EDM cut.
Charging handles are manufactured on site.
P-415 and P-308 barrels start as Rock Creek 5R barrel blanks.
Initial machining operations ensure barrel concentricity.
Barrels are then contoured.
Barrel extensions are manufactured in house. It costs POF more to grind the inside and outside of the barrel extensions than it would to simply buy off-the-shelf extensions.
Here, the single 1911-style feed ramp is machined into a barrel extension.
Closeup of feedramp machining.
Barrel extensions are attached and headspace is set. Gas ports are drilled after this step.
The next step involves barrel fluting.
12" .308 barrel, left; 11.5" 5.56 barrel, right.
Production costs for each gas block include a beautiful TIG weld. It's probably unnecessary, but again, Frank doesn't like to cut corners.
The inside of every gas block is honed at this station to ensure a precise barrel/gas block fit.
Barrels awaiting their gas blocks.
Before nitride, gas blocks and barrels are drilled for taper pins. The two parts are then serialized, separated, finished with a nitrocarburization process, and reassembled with their "siblings".
Barrel nuts are torqued to at least 40 ft/lbs.
Assembled uppers awaiting handguards.
Handguards awaiting their uppers.
Assembled uppers being prepared for shipping.
P-415 rifles in the final stages of assembly.
Every POF upper and rifle is test fired with a variety of ammunition before it ships.
I'll be writing follow-ups and more detailed explanations shortly, but I think they deserve their own posts.
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26Mar/101

Bravo Company MFG Mk12Mod0 Upper Receiver Group

Posted by Andrew Tuohy

What do you get when you order an upper receiver group from BCM?

You get a box...

Inside the box are a hat and a shirt (you may not get a shirt)...

There are also some stickers and a catalog...

A generous amount of bubble wrap is also included...

Inside the bubble wrap is some sort of long, cylindrical shaped object...

It's a faithful representation of the military Mk12 Mod0. For those of you not familiar with the Mk12 program, click here.

I'll be getting many more close up shots of the upper later today and will have a range report by the end of this weekend, although I will be breaking the upper in according to strict procedures, so there may not be an accuracy report just yet.

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24Mar/106

Smith Vortex vs. AAC Blackout

Posted by Andrew Tuohy

I'm not going to lie. Before I completed this test, I thought the AAC Blackout was all hype.

I thought AAC had engaged in shady marketing practices in order to show that their flash suppressor was superior to the competition, namely, the Smith Enterprises Vortex. I figured that I'd be spending $50 to pick up a Blackout and that I'd lose $10 reselling it after I did the comparison (maybe more than $10, if I said really bad things about it).

I was wrong.

Now, if you've seen my previous video comparing flash suppressors (or someone else's comparison of popular muzzle devices), you know that the Vortex was the most effective, eliminating nearly all visible flash. So it's not as if the Blackout could improve on the Vortex by a great amount - it's not as if the Blackout could create a black hole or anything. But what the Blackout could do - and, in my limited testing, did do - was eliminate what tiny bit of flash the Vortex couldn't.

Here's today's video. I start out with the A2 flash suppressor to establish a baseline for comparison. The weapon used is a Spike's Tactical M4 LE, a 16" barrel AR-15 with a carbine length gas system. The ammunition used is Federal XM193F, which is, I feel, a fairly common round.

I haven't sat down at the bench to determine if either device has an effect on accuracy, but if you're looking for a muzzle device that eliminates as much flash as possible, I recommend that you strongly consider the AAC Blackout.

Note - I apologize for the poor quality of the night vision video compared to the previous test. I think my video camera may have been damaged during a recent outing, and it's not taking video as clearly as it used to, especially in low light. My view through the PVS-14 was perfect, but the camera couldn't keep up.