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300 Black Out fired in a .223

The cartridge was designed wrong making 300BO actually fit in the chamber so easily.I was thinking about building one and this article makes me take a pause.
 
This exact reason is why I never wanted this caliber, second was the manufacturers REALLY over hyped promotion and performance of it. (yea maybe close quarter combat subsonic bullets loaded backwards stuff)
They should have been made it to never chamber in a .223 or 556.....but simplicity sells
Extremely dangerous and I don't think I've heard of another combination quite like this.
I think you can get some higher powered modern 7mm ammo to fire in some old Mausers that aren't built to handle it but others would know more.
 
So I guess that since a 300 blackout can be fired in a 223 chamber it should be outlawed.

What do we do about a 308 that can be chambered and fired in a 25-06 chamber?

Blaming the cartridge design is just plain stupid.

Let’s see what SAAMI says about unsafe cartridge combinations

Due to the availability of many different shapes and sizes of ammunition and firearms, there
are countless unsafe ammunition-firearm combinations such that a comprehensive list of unsafe
combinations is neither feasible, nor practicable. Below is a list of some unsafe combinations that
are well known because of somewhat similar chamber and ammunition dimensions.


 
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So I guess that since a 300 blackout can be fired in a 223 chamber it should be outlawed.

What do we do about a 308 that can be chambered and fired in a 25-06 chamber?

Blaming the cartridge design is just plain stupid.
This thread has taught me that inanimate objects really can be responsible for bad things that happen.:)
 
I don't think anybody mentioned outlawed....I've reloaded for 25-06....never worried about accidentally
loading a .30 cal cartridge in it .
That sammi list says you can maybe mistakenly load .40sw in a 9mm? 44 mag in a sp. a .357 in a sp.
Just my opinion and not trying to debate the issue, in the last 10 years or so and the popularity of the 300BO and AR cousins that swap uppers in 30 seconds on a tailgate is just asking for trouble
I love glocks but search glock blowups, It's not the guns fault
 
Here I thought the 300 BO was designed to be shot suppressed with a 180 to 220 gr bullet. A case, bullet combination that should not be able to chamber in a 223 or 5.56 rifle. If you want cheaper heavy bullets, CAST BULLETS is the answer
The waltz is fine, but sometimes you have to let it go and do some rock and roll.
A25E7D8E-4D4C-4B59-B472-3784ED22AC9D.jpeg
5402246C-2217-4C4A-826C-FD4A7E34DD38.jpeg
85 grain T-Rex by Maker Bullets
To be honest I cheated and used an 18” barrel to get that over 3k, it’s only 2800 and change in a 12”
 
OK^^^^^^^^^^that's definitely getting there. That is some wicked expansion.
I'm from the 6.8spc clan (85-95 barnes ttsx and others 120sst) but looks like that load can get it done!
 
Just like anything else when shooting......
Pay attention to what you are f@#~€*g doing.
It seems to be proven daily, Common sense is a super power
 
OK^^^^^^^^^^that's definitely getting there. That is some wicked expansion.
I'm from the 6.8spc clan (85-95 barnes ttsx and others 120sst) but looks like that load can get it done!
The only problem is it’s so short and light the BC suffers, I figured it around .185-190 by drops. Sheds velocity pretty quick.E9C456AA-09FA-4A16-B7BE-66255FCF9C2F.jpeg
100F0710-BCB5-4D92-B8BD-E622C361290F.jpeg
It’s a pretty well designed bullet. It uses the the whole thing. .885” long with a .135” tip. Lost around 1 grain, this bullet weighed in at 85.4 hitting the gel at 2800fps. Still has double caliber expansion at 1300fps.

I know he makes at least 6-8 .277” Bullets.
 
What's the big deal... YouTube has plenty of examples of this exact event. I even had a guest kindly destroy a $1200 Daniel Defense upper putting a 300BO round (125gr TNT) into a 5.56 mag by accident/ignorance . There is a reason DD has a loyal following. It cracked the receiver and split the BCG in several locations when the bolt got slammed backward into the BCG. There was no more brass case, but rather a brass coating of the chamber and portion of the barrel. You can see how far it flowed back into the bolt (ejector pin and firing pin). Only the base of the case remained intact as it melded itself to the bolt face. I finally had to cut through the extractor in order to get the bolt to release from the chamber (2nd picture).

DDM4 #8.jpg

DDM4 #11.jpg

Lessons Learned - Solutions (Belt & Suspenders):
1) Never comingle the two guns
with other shooters. Only one caliber out at a time. Literally, 300BO rifle out and its loaded magazines. Put it all away and make sure no loose rounds on the ground or bench. Only then does a different caliber AR15 come out of vehicle.

2) Preload all magazines so no loose ammo or loading done while at range. This eliminates the risk of a guest doing something without realize the difference in the cartridges. I transport the mags stored in separate lidded containers, and only bring out the mags/ammo for the rifle that is in use.

3) Dust Cover with caliber etched on both inside and outside so that it is always showing whether dust cover is open or closed.

4) Hi-Viz Magazine Bands to easily recognize different caliber ammo. I even use a different color to depict supersonic and subsonic for my 300BO.

5) Different type of magazines so that both by appearance and feel they are easily distinguishable. Yes, that means I have invested an extra few hundred bucks to reduce risk of blowing up another rifle or ER trip for an injury.... cheap money. I use PMags for 5.56/.223 and Lancer Mags for 300BO.
 
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So I guess that since a 300 blackout can be fired in a 223 chamber it should be outlawed.

What do we do about a 308 that can be chambered and fired in a 25-06 chamber?

Blaming the cartridge design is just plain stupid.

Let’s see what SAAMI says about unsafe cartridge combinations

Due to the availability of many different shapes and sizes of ammunition and firearms, there
are countless unsafe ammunition-firearm combinations such that a comprehensive list of unsafe
combinations is neither feasible, nor practicable. Below is a list of some unsafe combinations that
are well known because of somewhat similar chamber and ammunition dimensions.


Sure, but it's pretty common for people to have the particular combo in question at the range at the same time using the same mags in the same guns. I've never even seen a 25-06 at the range.
 
I have both and never considered this possibility.

Wonder what a 223 in. 300BO upper does?
If it would fire then probably about what the 6s shot in a 7 next to me at a match once did, rattle around come out the end and leave the shooter puzzled as to why he's not getting to the target until he takes a good look at his brass.
 

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