5.56 Timeline

Shooter fires 300 Black Out Through a 5.56MM

The old 300 blk out/ 223 mix up strikes again. B-ARFCOM user Plank_Spanker shared this story and picture about his very lucky but yet inattentive buddy.

So a buddy of mine was at a range doing some shooting a few weeks back.
Shooting both .223 Rem & .300 BO uppers on a single lower switching back & forth.

He somehow got a .300 BO round mixed in & extruded it halfway down the barrel of his .223 Aero upper.
At that point he didn’t realize what happened. Bolt jammed up couldn’t mortar it out.
He brought it to my place & I was able to get the bolt free & low & behold, a .300 BO casing was stuck in the bolt. Popped primer fell out too.

When the rifle jammed up, he said it made a “pop” & like cooked off the propellant with lots of smoke. I had read that same description in another thread here.
I didn’t have a rod to try & pound it out so he took it to his LGS & had it removed.
We are all amazed that it didn’t kaboom the rifle. The .300 was a subsonic round.
Smith said the barrel & bolt were fine

He wants to have a jeweler mount it on a chain as a reminder, I told him it would be a better reminder as a butt plug.

Be careful out there.



I ran across this little piece over at tinfoil hat constant doom website extraordinaire, zerohedge. Sometimes there is some pretty interesting stuff there and this is one of those times. It’s amusing to look at these prices and the cost for a legally transferable Class 3 M16. I won’t mention the tax payer money spent to buy these originally since its so close to tax season.

In 2017, Statista put together an infographic about the price of an AK-47 on the black market and the weapon had an average cost of anywhere between $1,135 in Belgium and $2,100 in Syria. Calibre Obscura, a fascinating website and Twitter account devoted to research on arms in the hands of non-state groups, has now published data on the average price of an M16 in various countries.

Focusing on the Middle East and North Africa, the price levels are based on local sources, focusing on the M16A2 and A4 variants of the American assault rifle in late 2019. Those weapons end up on sale in a variety of ways from the Taliban capturing them from Afghan army and police units to those same security forces themselves deciding to sell their weapons to various groups. It is also likely that U.S.-manufactured weapons have been captured from Saudi forces in the Yemen conflict where they have subsequently gone on sale.

As the chart shows, perhaps the great arbitrage trade in the world is shipping M16s from Syria to Lybia… just be careful…

Infographic: The Average Cost Of An Illegally Purchased M16 | Statista

You will find more infographics at Statista

Across the Middle East and North Africa, the gun has the highest average price in Tripoli where it is said to cost in excess of $12,000, though it is thought to be practically unobtainable there.

Elsewhere, it’s far cheaper, however, fetching between $2,500 and $3,000 in parts of Yemen.

In Helmand province in Afghanistan and Idlib in Syria, the weapon can be purchased for less than $1,000.

Silencers and Semi-autos – A Parable

Imagine that you have a friend who is ready to buy his first AR15. Instead of following any reasonable advise, they go to a gun show and buy a random AR from one of these fly by night companies no one has ever heard of before or will hear of again.

Then they have some issues. Not being the sort to just settle, they work them out. Now your friend goes online and is is an “experienced expert” on the AR15. They go into great detail on how you have to take the gas block off and open up the gas port with a drill to get the gun to be reliable. How you need to take a file and open up the back of the mag well so that magazines will seat correctly. How there are so very many things you need to do to make an AR15 a reliable combat worthy firearm.

You try to tell them that none of that would have been necessary had they bought the right AR15 to begin with, but instead they insist that this work needs to be done to ALL AR15s.

Wouldn’t that be pretty damned infuriating? In the good ol’ days you might punch a man in the face for being so obstinately wrong, but we are more polite than that now.

There are people out there who claim that you have to use an adjustable gas block with a silencer. That all silencers cause excessive back pressure. That you need to switch buffers or change the gas system when running a silencer on an AR15.

This isn’t a matter of someone buying a cheap junky silencer to put on a cheap junky rifle, this is a matter of compatibility. Someone can buy a top of the line silencer and throw it on a semi auto and run into issues because the silencer was designed with bolt actions in mind. It might be the best silencer to put on a bolt action, but no consideration was made as to back pressure with that design. So when they throw it on a semi-auto, suddenly they have an over gassed gun. Now this expert tells everyone that every silencer will cause an over gassed gun. No, your bolt gun silencer will cause an over gassed semi-auto.

I saw a post on a forum today where someone was wanting to suppress a standard M4 configuration AR15. They said that they knew that a mid length 14.5 would be better for being silenced (WTF did that come from? Someone show me the research that says that.) This person was worried if it would even work at all, or if they would have to get an adjustable gas system and tune the buffer weights, etc.

Fortunately several people responded that they had the same setup and didn’t have to change a thing.

Yes, all guns can be tuned and improved, and that isn’t what I am talking about. I’m talking about those loud mouthed know-it-all’s, that once tried to make a soup sandwich and failed, that now claim that all sandwiches are bad.

Understanding the USMC new ACOG reticle

The Marines started using a new ACOG reticle in the Squad Day Optic (SDO) on the M249 Squad Automatic Weapon (SAW). That optic got moved to the M27 IAR when the USMC switched over, and now the Corps is having the 4X Rifle Combat Optics (RCO) scopes get this reticle.

Simple, right? Pretty much self explanatory. I feel like I would be insulting your intelligence to explain how to use it.

But, just in case you weren’t clear how to use it, I’ll explain.

First, back ground info:
M249 SAW has been available in various barrel lengths. I’ve seen different numbers thrown around, but 16.3 and 20.5 inches seem to be the official lengths.
The M4 and M4A1 has a 14.5 inch barrel, and the M16 series of rifles has a 20 inch barrel.
M27 IAR has a 16.5 inch barrel.

Previously the USMC fielded two different ACOGs, the TA31RCO-A4 (AN/PVQ-31A) and TA31RCO-M4 (AN/PVQ-31B) for the 20 inch rifle and 14.5 inch barreled carbine respectively.

There is a rumor that Trijicon used the same BDC in each scope, but I don’t believe that. I do know that back in 06-07ish, higher ups in the USMC claimed that the scopes were interchangeable. I think that it shows that the level of precision considered acceptable by the USMC allowed either scope to be used.

The SDO optic, adopted for the SAW, needed to be able to work for either barrel length. It used this reticle with green illumination.

Blah blah blah, let us talk about this reticle. I could type up an explanation, but it would be easier for me to copy and past from the USMC own Squad Weapons manual.

First Zeroing:

Ideally you zero at 300m using the tip of the post. If not that, then use the top of the dot at 100m. Reduced range zeroing can be done using the tip of the post at 33m/36 yards for the M16.

Unlike the RCO models which had a Chevron and Bullet Drop Chart (BDC) that went out to 800m, these have a BDC that goes out to 1000m.

Note the narrower lines below the marked lines. We will come back to that in a moment. Those are important.

Ater the 500m line, instead of using a line to cover your target to estimate range, the SDO reticle has a gap. You fit the torso of your target into these gaps to find the distance to them when you are using the 600-1000m section of the reticle.

What are all these smaller lines below the BDC range lines?

As previously explained, we have these 14.5-16.6 inch barreled guns, and 20-20.5 inch barreled guns. The lower smaller line is for the ballistics of the shorter barrel.

This scope had a BDC for the rifle and the carbine (or the Para-SAW and the standard SAW). This lets the USMC have a single ACOG that can work on the M4/M4A1, M16A4, M249 (regardless of configuration), and the M27 IAR.

I’ve shot out to 1000 yards (~914m) with an ACOG and it is far from ideal for that job. But it is far better than using iron sights at that range. While stuffing a 1000m BDC in an ACOG may be idealistic for the one shot one kill rifleman, it very useful tool for the automatic rifleman’s suppressive fire. It is better for our troops to have it and not need it, than the other way round.

Thanksgiving Plinking

Went to the range today. Hadn’t shot shotgun in a while and was starting to grow fond of them. A few shots reminded me why I don’t care for them. Low capacity, slow to reload, etc. Still worth having one.

I received a Geissele Super Dynamic 3 Gun trigger (SD3G) in that Larue PredatAR rifle I talked about recently. I replaced it with a Larue MBT trigger in that rifle. I am going to sell this trigger, but I figured I should it before I do. In the past, when I used a Super 3 Gun trigger (S3G) I found it so light and the reset so short that I was inadvertently getting double and triples when I didn’t want it. That happened with two different lowers, so I quickly got rid of the trigger. Trying this one in one of those same lowers, I had no issues with unintentional bump firing. Geissele’s “3 Gun” triggers are very light, short trigger, and very quick to reset. It makes for a very easy to shoot fast firing gun, but I’d rather have heavier trigger for any gun that I would expect to use for any serious or dangerous work. Still, something like the S3G or SD3G triggers would be perfect for the gun games they are designed for. The S3G has a standard curved trigger, while the “Dynamic” SD3G has a straight trigger.

I’ve started playing around with the Magpul 40 round Pmags. Initial impressions are excellent. They are easy to load, smooth to use, standard Magpul AR15 Pmag excellence. I expected they might be so long as to be awkward but I was wrong. As of now, I would wholeheartedly recommend them.