Otherwise, this might happen.



More pics of destroyed gun parts at link .

This message has been edited. Last edited by: BBMW,

Thw shole set of pics is on the fire arms blog.

It is a 16 ich barrel.

Lesson learned....only12 inch 556 barrels for firing 300aac out of.

quote:

Originally posted by DSgrouse:

Lesson learned....only12 inch 556 barrels for firing 300aac out of.

Haha. Truthfully I’m shocked it made it as far down the barrel as it did.

My 300 Black out charging handle is red --just so I won't make that mistake. I figured better to color code so it is easy to identify.

quote:

Originally posted by SIGfourme:
My 300 Black out charging handle is red --just so I won't make that mistake.

Good idea.

What this really demonstrates is the need to be exceptionally careful about having guns chambered for different cartridges on the shooting bench at the same time. Fortunately my screwups (9mm and 357 SIG in 40 S&W) didn’t cause any major problems, but after the second time that lesson finally sunk in. In thinking about this one, though, I realized that I’m not the only person shooting at most of my sessions, and sometimes they’re using different ammunition than I am.

If I had a 300blk, I would have an entirely different color for my mags, and would spray the mag well of that rifle as well.

I have PMAGs for my 5.56. I bought brown metal 20 round mags from Brownells to use with my 300blk.

No, the 300BLK guys say that it's IMPOSSIBLE!!!!



I wonder if it was a smaller, lightweight supersonic load. Most of the time when you see this happen with bullet setback the upper is shattered.

I have a 300 Blackout stamped ejection port cover on my .300s

At one of my old jobs, we used to see these a dozen or more times a year:


( M855 5.56 round for scale )

.300 blk will fire and travel down a 5.56 barrel... to a point.

I was under the impression that you couldn't chamber .300blk in a 5.56 breach/barrel.

I'm building a .300blk, and I'm not very smart, so this whole color coding thing may need to happen.

I'm going to color code, after a fashion. My SBR 5.56 and .300 BLK (when the stamps come back) are going to be different colors. One will stay black and the other is going to get camoed FDE of some sort.

I don't really know if color coding mags is necessary if the guns are obviously different colors, although I guess spraying a bunch of mags one color while doing the rifle wouldn't be all that difficult.

Wonder how far one of my (AR) .450 Bushmaster rounds will go down the barrel. Here. Hold my beer...

quote:

Originally posted by MikeGLI:
I was under the impression that you couldn't chamber .300blk in a 5.56 breach/barrel.

Yeah that's a common misconception.

It really depends on the load of 300BLK and if the round experiences bullet setback, but if you google for events like this, you'll see plenty of examples of how it can and does happen with some regularity.

This is a duh moment for me. I meant for the link in the OP to be to the one below, but I copied the wrong address. I fixed it now.

Sorry

quote:

Originally posted by DSgrouse:
https://www.thefirearmblog.com...t-in-a-556-barrel-16

quote:

You probably don't want to fire .330 BLK out of a 5.56mm barrel.

I used to like idea of ARs chambered in cartridges that used the same case as the 5.56x45 necked to different calibers, like .300 blk, or the much more obscure 6.5mm PCC. Now I'm thinking the possibility of catastrophic confusion might be too big, Maybe rounds that won't chamber in the wrong gun (6.8 SPC, 6.5 Grendel, etc.) are a better idea.

At the risk of being CW3 Obvious, I’ll stress my own opinion on this.

Murphy identified it long ago: “Whatever can go wrong, will go wrong.” If the situation makes it possible to load 300 Blackout ammunition in a rifle chambered for 223/5.56 and fire it, it will happen. Color coding and labels are great, but they rely on shooters’ thinking about what they’re doing. And if we are thinking about what we’re doing, then all that’s necessary is to look at the rifle, look at the ammunition, and not do the wrong thing. The problem is that most of us don’t always think about what we’re doing.

A safer way is to not rely on keeping things straight when we’re actually shooting, but to separate the ammunition and guns before we’re shooting. Safest is to take only one type to the range, but it’s pretty good if things are separated in our vehicles and only one type is taken to the firing point at a time. Color coding or other markings are useful for quick identification—when we’re paying attention—but they’re not a guarantee.

(All that is just one of the many firearms safety rules I try to follow beyond “the” four.)

I have Ruger American Ranch Rifles in 5.56 and 300 BLK with identical Vortex scopes on each. In order to prevent grabbing the wrong rifle, they both have a white label with the caliber printed in large type(on the rear bell of scopes). The .223 version also has a stock pouch/cheek rest for further visual cues. Then there are the same magazines to keep from switching. I really have to be watching, mags unloaded and grand kids no touch. I now leave one rifle at home for range trips