50wt
NES Member
No, the 300blk uses the same bolt as 223/5.56
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Almost had a real bad day
- Thread starter NH_Realtor
- Start date
No, the 300blk uses the same bolt as 223/5.56
nstassel
NES Member
Avoiding the .300BLK AR-15 ‘ka-boom!’
The .300 Blackout cartridge is a flexible, innovative cartridge that's a step up from .223 but not quite the full-power of .308, all in an AR-15-sized rifle. However, accidentally loading .300BLK into a .223 gun can have catastrophic consequences.
allen-1
NES Member
wow.
I've been at two matches where guys blew up guns, a Glock 17 and an AR-15. Both had minor damage to their hands and major damage to their shorts. The G17 was loaded with the shooter's reloads, and he has a certain reputation. The shooter of the AR-15 thought that he might have mixed a 300BO into his ammo can, (just like OP).
Looking at their guns, I considered both of them lucky - and OP falls into that same category - damage could have been a lot worse.
Hope your day on the range today goes better.
I've been at two matches where guys blew up guns, a Glock 17 and an AR-15. Both had minor damage to their hands and major damage to their shorts. The G17 was loaded with the shooter's reloads, and he has a certain reputation. The shooter of the AR-15 thought that he might have mixed a 300BO into his ammo can, (just like OP).
Looking at their guns, I considered both of them lucky - and OP falls into that same category - damage could have been a lot worse.
Hope your day on the range today goes better.
amm5061
NES Member
.300 blk is just a necked up .223 cartridge, so yeah, same bolt handles both.
fresh unopened bag today... no mistakes
xtry51
NES Member
Oh snap. I didn't realize this.
Good info and tips. After reading this discussion, I will definitely take more precautions. Maybe even the 'one at a time' method described in the article.Avoiding the .300BLK AR-15 ‘ka-boom!’
The .300 Blackout cartridge is a flexible, innovative cartridge that's a step up from .223 but not quite the full-power of .308, all in an AR-15-sized rifle. However, accidentally loading .300BLK into a .223 gun can have catastrophic consequences.www.nrablog.com
Thanks
In God We Trust
NES Member
I figured .300 was less pressure than a .223 glad you are ok.
I bought a bucket of .45 from a dude at work and there was a random .40 round in there I I didn’t notice. Made a hollow pop when I fired it and didn’t cycle the action. No damage to the gun.
I bought a bucket of .45 from a dude at work and there was a random .40 round in there I I didn’t notice. Made a hollow pop when I fired it and didn’t cycle the action. No damage to the gun.
Mesatchornug
NES Member
Maybe less pressure in normal operating conditions...not sure sticking a .30" bullet in a .22" tube counts
xtry51
NES Member
On a rare occurrence in past I've had a 380 piece of brass make it thru to my 9mm reloading station. Fortunately you just get a failure to cycle. Maybe 3 times in last 10 years and roughly 40k rounds.
I had a kaboom out of a fairly reputable companies AR. Was, I think, more of an out of battery type fire.
Normally I'd suspect, like I mentioned before, I somehow fired a 7.62 Russian I loaded in the mag, but the way it started was an otherwise reliable rifle had jammed up a few ways in between normal firing. And it actually had one ftf where I opened it up on the spot, barrel/chamber was clear, and otherwise saw nothing wrong, checked ammo, kept going. Ran a mag ok, somewhere in the next mag sounded like a rush of air, mag fell out and ammo spit onto the ground, bcg was jammed like yours.
Suspect a mechanical failure with bcg somehow that wasn't obvious or maybe a hunk of a case was torn off and floating around that did something wierd. Company sent me a new rifle, which was really cool since original was a "blem". Plastic mags IMO are a good thing - an easy path for pressure to escape on the underside of the rifle. They sent the damaged mag I sent in back with the new rifle, attached pic - note the cracked "flap" on the mag.
Note: despite my plea that they just replace the upper, after a kaboom of any sort standard practice says lower may be over stressed and unable to withstand a 2nd such malfunction without blowing up. The company insisted on sending me a complete new rifle. Probably is more of a liability thing but for the low cost of a lower, probably makes sense.
Normally I'd suspect, like I mentioned before, I somehow fired a 7.62 Russian I loaded in the mag, but the way it started was an otherwise reliable rifle had jammed up a few ways in between normal firing. And it actually had one ftf where I opened it up on the spot, barrel/chamber was clear, and otherwise saw nothing wrong, checked ammo, kept going. Ran a mag ok, somewhere in the next mag sounded like a rush of air, mag fell out and ammo spit onto the ground, bcg was jammed like yours.
Suspect a mechanical failure with bcg somehow that wasn't obvious or maybe a hunk of a case was torn off and floating around that did something wierd. Company sent me a new rifle, which was really cool since original was a "blem". Plastic mags IMO are a good thing - an easy path for pressure to escape on the underside of the rifle. They sent the damaged mag I sent in back with the new rifle, attached pic - note the cracked "flap" on the mag.
Note: despite my plea that they just replace the upper, after a kaboom of any sort standard practice says lower may be over stressed and unable to withstand a 2nd such malfunction without blowing up. The company insisted on sending me a complete new rifle. Probably is more of a liability thing but for the low cost of a lower, probably makes sense.
Artifact
NES Member
Glad you are okay.
Be careful even if you think the lower receiver looks ok. I have seen crazier shit happened.
Original boxed ammo gets loaded like second nature. Anything opened, loose rounds etc gets double checked. I like to load without gloves as I like to feel each round as I am picking it up and loading. I have had effed up rds that were, dented and or projectile pushed in further that I wouldn’t have felt with gloves on. Ideally you want to do both, visually and tactile feel.
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safetyfirst2125
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Should be fine. Throw a little gun oil on that and it’ll be good to go.
I don't really think it was a smart move to of made 300blk that interchangeable with 5.56x45. Tons of people have blown up guns and there's no doubt in anyone's mind that it's going to keep happening. Shit happens. And people regularly, and I mean regularly mix up ammo like this. Everything is interchangeable until you pull the trigger. i think that's a little silly.
skinflints will skinflint, though. Which is why its so interchangeable.
That's a great illustration of why it can fit but why many think it cannot. Because of the case and shoulder length difference and with the spire point projectile.
I don't shoot 300BLK much but I'm always very careful to visually check a mag before it goes in the gun.
Wow, a crazy scenario. I shoot 300BO, 220gr subs and i had no idea this could happen. So for my own knowledge a 300bo round can fully chamber and allow the firing pin to strike and ignite the round ?
True dat!
Apparently it was the military design specification for the round. The military loves interchangeable things for logistical reasons. Might need to factor in the logistics of having more gun parts on hand, though. As I was reading this thread, I kept thinking about how bad of a situation it was to opt in to, but OTOH, I kept thinking, damn, wouldn't it be a lot of fun to shoot 300 BLK versus 5.56 at short range, especially suppressed. I get why people want it. Bad situation, though.
![[laugh]](/xen/styles/default/xenforo/smilies.vb/012.gif "Laugh [laugh]")
wow if the military requested that it's even more insane. The military usually tries to dummy proof things. Theres a reason the front side is marked on a claymore
![[rofl]](/xen/styles/default/xenforo/smilies.vb/013.gif "ROFL [rofl]")
300 blk is a cool round. Just a shame that this is how it's going to be with it. If I bought it I doubt I'd fire a 300 through a 5.56 upper. However, as mentioned, shit happens. I've had 5.45x39 mixed in with 5.56x45 on more than one occasion and that has been also know to be a spicey meatball when you get those 2 f***ers mixed up.
I have a 220 gr cast dummy round that i use for setting my handloaded subsonic bullet seating depth. Going to test tonight and see if it can fully chamber and allow the firing pin to function in a 5.56 chamber.
Number one reason I will not own a 300blk.
This is also why painted my Uzi Swedish training ammo barrel Ford blue on the front two inches and label the ammo, NOT FOR REGULAR 9mm USE, REQUIRES SPECIAL BARREL.
Glad you were uninjured.
This is also why painted my Uzi Swedish training ammo barrel Ford blue on the front two inches and label the ammo, NOT FOR REGULAR 9mm USE, REQUIRES SPECIAL BARREL.
Glad you were uninjured.
Mesatchornug
NES Member
I think this is one of those "difference between theory and practice" problems.
I (quickly) copied the SAAMI specs for 223REM and 300AAC into CAD. The orange line is the 300 cartridge; the green is the 223 chamber. In theory it shouldn't load...
Now, change the profile of the bullet a little, set it a little deep, or any of a handful of other issues, and it "might fit."
Worse still, if your bullet is not sitting on top of powder, you might even be able to set it back just from the closing of the bolt. I'm not accusing the OP of the following, but I'm sure occasionally a user might employ their forward assist to make sure it goes...
I (quickly) copied the SAAMI specs for 223REM and 300AAC into CAD. The orange line is the 300 cartridge; the green is the 223 chamber. In theory it shouldn't load...
Now, change the profile of the bullet a little, set it a little deep, or any of a handful of other issues, and it "might fit."
Worse still, if your bullet is not sitting on top of powder, you might even be able to set it back just from the closing of the bolt. I'm not accusing the OP of the following, but I'm sure occasionally a user might employ their forward assist to make sure it goes...
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