KABOOM . . . 300 Blackout >>> BLOWS <<<< in a 556 . . . What?

[OS OK]

Kaboom...the story of two different rifle frags one of them on video, but...it's the second Kaboom that I am having trouble with in my mind. How the heck will the 300 blackout chamber? I dunnoh, I don't load for or shoot either one.

It's interesting....perhaps someone here can figure this one out?

https://www.youtube.com/watch?v=-cVPAd4k7UU

[Madoktor1]

Same case but shorter length. 556 has a longer leade in the chamber. I would say very possible for 300 BO to chamber but, as stated in the video, the Bullet won't go far.


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[sawinredneck]

I still say the first was a squib, the bullet should have sealed the chamber enough to have made some sort of "bang". Loose neck tension, a primer with no powder, I'll buy that.
I have a hard time with the .300bo, but I honestly don't know the specs well enough to refute the post above.

[303Guy]

Looking at the cartridge specs I would say the only way a 300 Blackout can chamber in a 223 is for the bullet to get pushed back into the case. The cartridge would then headspace on the pushed in bullet, possibly against the powder holding the bullet forward.

[Artful]

Light weight bullet in 300 blackout has ogive back far enough to chamber
http://blog.westernpowders.com/wp-content/uploads/2014/03/300-ACC-Blackout72.jpg

Heavy weight 300 blackout vs light weight 300 blackout
http://www.defensereview.com/wp-content/uploads/2010/10/300_AAC_Blackout_Cartridge_6.jpg

[Cowboy_Dan]

The two above have it. To make the brass for the blackout, .223/5.56 is cut short and the shoulder moved back. After this it is possible for a blackout to headspace on the ojive of the nose jn a .223 chamber. Conversely, if a .223 is tried for chambering in a blackout, it will stop on the shoilder and hang out the back of the rifle (or at least the cartridge gauge I tried it on).

[OS OK]

OK...that's what I suspected, only this...the only 300BO casts I've seen have been the 220 grain...huge in comparison to the 556, I thought it must have been pushed back in the case.
I still thought it would take some banging away at the bolt to get her to go into battery though...

oh well, live and try to learn at someone else's expense!

[KVO]

Yep, bullet setback. Same thing can happen chambering a 7.62x39 in a 22-250. I didn't believe it was possible until I tried it (with a dummy round, no powder or primer)! One would think that having to hammer on the bolt should be a sign to take pause.

[KVO]

I do applaud AMTAC for sharing that video. Valuable learning opportunity and I respect a measure of humbleness.

[Elkins45]

202788

Hope this image shows up. As stated, a light short bullet or bullet setback will allow a 300 to chamber. Heck of a resizing job! That's one long skinny 22 caliber bullet that used to be a 30.

[sawinredneck]

They couldn't just drive that bullet out and reuse the barrel?

[Elkins45]

They couldn't just drive that bullet out and reuse the barrel?

People are just so wasteful these days!

[303Guy]

That bullet would never have stabilized anyway. :mrgreen:

Actually, it's more like an arrow.

It's scary how wrong cartridges can chamber. 308 in 270. Apparently without bullet setback.

But this thing about banging a cartridge into battery when it won't chamber. One would think we would stop and think there is something wrong! But no, it happens. I won't tell you how I know. :roll:

Using a case filling powder does have it's advantages.

[Texas by God]

The normal advice on loading .300 BO is to match the bullet ogive to the shoulder location of the .223 for reliable function. And that is why the .300 will chamber & fire in a .223.
I demonstrated this to the guys in our deer camp last fall because many use ARs for hogs.
Now all .300 mags are marked as such. Let's be careful!

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[Moonie]

I fix this issue 2 ways, I do not own a .223/5.56 upper and I load only loads that will not fully chamber anyway, much longer than required to chamber.

[Texas by God]

Okay......

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