GotRDid
Gold $$ Contributor
So, you absolutely need RN and SP construction?
Fell Victim to the 300 Blackout
- Thread starter MGYSGT
- Start date
I totally understand where you are coming from, but like above, being that you are in AZ the difference from sea level may make them sub sonic. I am at Camp Lejeune, but have my farm in Ohio. I do most of my testing in NC, but have found that in Ohio, i get different results (1000 ft difference). Sound from the can is what I'm looking for. Other wise, why sub sonic. My go to for subs are 150gr round nose 30-30 bullets. Sometimes I'll get 170gr, but they both shoot well!
By the way, nice to meet you MGYSGT, this is Top Rob!
Forum Boss
Administrator
.300 Blackout. Not such a good design. We see one of these blow-ups on the web every couple of months because the .300 BLK will chamber in typical .223 Rem barrels.
bulletin.accurateshooter.com
.300 Blackout Fired in .223 Rem — Mistake Is Disasterous « Daily Bulletin
Photos and Facebook post by Tactical Rifle Shooters Yet another .300 Blackout disaster. Unfortunately, that .300 Blackout cartridge can fit in a .223 Rem chamber. Shooting a .308-caliber bullet in .223 bore is a recipe for disaster. <img src=https://accurateshooter.
dellet
Gold $$ Contributor
While I fully recognize the problem exists, I wonder why we rarely if ever see or hear about.300 Blackout. Not such a good design. We see one of these blow-ups on the web every couple of months because the .300 BLK will chamber in typical .223 Rem barrels.
View attachment 1284429
.300 Blackout Fired in .223 Rem — Mistake Is Disasterous « Daily Bulletin
Photos and Facebook post by Tactical Rifle Shooters Yet another .300 Blackout disaster. Unfortunately, that .300 Blackout cartridge can fit in a .223 Rem chamber. Shooting a .308-caliber bullet in .223 bore is a recipe for disaster. <img src=https://accurateshooter.
View attachment 1284430
223 bolt actions blown up with 300 Blackout rounds
280 Remington/30.06 based rifles blown up by .308 win. based cartridges
There are so many different combinations where this potential exists, but it only seems to happen to 223/556 AR owners who chamber Blackout rounds.
Is it a poorly designed cartridge?
Poorly designed rifle?
Poor thinking by the operator?
Just something for people to think about.
I'll tackle this one since I have first hand experience with the Blowing Up part.
Wrong cartridges get placed into bolt rifles periodically, but since everything works so much slower with a bolt rifle is get caught sooner/more often. Also, bolt rifles have a more distinct, individual look from one rifle to the next so less likely to accidentally commingle guns and ammo. When was last time you were on 100-yard line and looked down benches and saw 2 guys shooting the same bolt rifle. Also, majority of bolt rifles still use internal blind magazine/hinged floor plate. It is hard to ignore/overlook the ammo as you are manually feeding the rounds either directly into the chamber or loading the internal magazine.
The increased frequency with AR15's is a function of overlapping equipment and speed of activity. Identical magazines loaded with both .223/5.56 and 300BO. Identical rifles used for shooting both cartridges with no real discernable markings. Frequent use of both calibers in close proximity and perhaps even by same person during same range trip.
Finally, the rate of activity and type of shooting lends itself to increase in risk. AR15's are shot faster while shooting from a bench at the range, hunting, and participating in various dynamic shooting sports. Grab a mag and shove it in. If you are using the same exact magazines (PMags) loaded with .223/5.56 and 300BO that are tossed into a bag then a moment of carelessness and you just distractedly loaded the 300BO mag into your 5.56 AR15.
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I thought I was being safe with a couple of friends and a guest shooter providing some informal training on AR15 platform. I had brought out AR's chambered in 5.56 and 300BO. We started with 300BO... ammo stored separately, etc. After finishing with 300BO, I returned the rifles and ammo to the car. I returned with 5.56 AR's and ammo. As magazines ran dry I allowed my friends to load up magazines from the ammo can of 5.56 ammo that I had brought out. I wasn't shooting but rather watching them closely.
What I hadn't planned for and what I didn't see happen was that the guest found a 300BO cartridge on the ground and didn't make a distinction of it versus a 5.56. He then loaded it into the magazine with the rest of the 5.56 ammo. Kaboom... death of a Daniel Defense, but more importantly there were no injuries.
My protocol now is that the 300BO have completely different magazines (really like the 300BO Lancer magazine) for visual identification along with a magazine bracelet (rubber) that states the specific caliber and also if subsonic ammo. On any AR15, other than 5.56 caliber, the standard dustcover is replaced with a custom dustcover ($30) that Boldly states the caliber on both sides of dustcover so that it is visible whether opened or closed. The final step when guests are involved is that I load all magazines (pre-loaded before arriving at range), and these loaded magazines are then stored in separate clear tupperware containers by caliber... no more loose ammo and no risk of commingling magazines. While shooting I don't bring out rifles that have "caliber risk" at same time. Before I switch calibers during a shooting session, everything is returned to the vehicle and I police the area to make certain no live ammo is left on the benches or ground,
Belt & Suspenders!!!
What I hadn't planned for and what I didn't see happen was that the guest found a 300BO cartridge on the ground and didn't make a distinction of it versus a 5.56. He then loaded it into the magazine with the rest of the 5.56 ammo. Kaboom... death of a Daniel Defense, but more importantly there were no injuries.
My protocol now is that the 300BO have completely different magazines (really like the 300BO Lancer magazine) for visual identification along with a magazine bracelet (rubber) that states the specific caliber and also if subsonic ammo. On any AR15, other than 5.56 caliber, the standard dustcover is replaced with a custom dustcover ($30) that Boldly states the caliber on both sides of dustcover so that it is visible whether opened or closed. The final step when guests are involved is that I load all magazines (pre-loaded before arriving at range), and these loaded magazines are then stored in separate clear tupperware containers by caliber... no more loose ammo and no risk of commingling magazines. While shooting I don't bring out rifles that have "caliber risk" at same time. Before I switch calibers during a shooting session, everything is returned to the vehicle and I police the area to make certain no live ammo is left on the benches or ground,
Belt & Suspenders!!!
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Jager
Gold $$ Contributor
Interesting story, Oso. Hat's off to you and all the other good folks out there who try and educate the uneducated.
But when you walk back and try and identify the "critical moment," it was when your guest decided to chamber and fire a live round he found on the ground. Maybe not doing that needs to be part of the protocol.
None of us are born with the knowledge and wisdom of how firearms work, so it's hard to put too much blame on your errant guest. But the shooting world is full of examples of things that have a very narrow, prescribed use case... and go sideways pretty much instantly when used outside that use case.
Alas, as we all know, there are lots of people out there who look at all that unsafe potential wed to the world of firearms and, intent on saving us from ourselves, insist that it go.
The .300 Blackout is a fine cartridge, blessed with remarkable utility. But those of us who shoot it must walk the fairly narrow path it lights in front of us.
Pretty much like all guns, and all calibers.
But when you walk back and try and identify the "critical moment," it was when your guest decided to chamber and fire a live round he found on the ground. Maybe not doing that needs to be part of the protocol.
None of us are born with the knowledge and wisdom of how firearms work, so it's hard to put too much blame on your errant guest. But the shooting world is full of examples of things that have a very narrow, prescribed use case... and go sideways pretty much instantly when used outside that use case.
Alas, as we all know, there are lots of people out there who look at all that unsafe potential wed to the world of firearms and, intent on saving us from ourselves, insist that it go.
The .300 Blackout is a fine cartridge, blessed with remarkable utility. But those of us who shoot it must walk the fairly narrow path it lights in front of us.
Pretty much like all guns, and all calibers.
What is the 1123fps based on? 65degF?
Add 50% Rh and Mach1 goes to 1168fps.
At 75degF and 50%Rh, M1 goes to 1198fps
1123fps would likely be transonic (if concerned about that).
True Subsonic for that dry mach would be ~898fps
Agree - For this reason I load all magazines in advance. Yes, I now own a lot of magazines. With guests I have a safety discussion in advance. I show them the different cartridges and then tell them my Kaboom story so that they know not to handle any ammo except the loaded magazines that I give them. Any unfired, loose cartridges are to be set aside and not used.
Also - I do a lot fewer teach & learn sessions... only with close friends. When possible they bring their own rifle and ammo.
Yes. You have to pay attention.
This is a long way from being the only cartridge capable of being chambered in the wrong firearm.
I watched two guys each with a 30-06 rifle. The one was really upset because his buddy's rifle kicked so little compared to his. When I looked the 'light' kicking 30-06 was being loaded with 270's! No harm done.
However I wondered if a 30-06 can be chambered in a 270? These guys were plenty strong enough to close a bolt. Thinking about it, I know there will an impressive 'jam' However to a point. Then wouldn't the bullet reseat itself deeper in the neck allowing the bolt to close?
If it can, you'll wind up with a similar picture that was posted above.
I'll guess at this one.
In the current time period here may be more of this combination of firearms out there than any other pair.
dellet
Gold $$ Contributor
Bullet set back due to light crimps are a large number of the problems 300 BLK in 223/556 chambers. Part of what allows that is light powder charges for subs.
There is a photo on the internet somewhere of 3 or 4 220 grain bullets stuck in a 223 barrel. That's just a plain stupid shooter.
The short cartridge being able to allow headspacing off the neck diameter of a longer chamber is not a new problem. If you search there are plenty of stories of 308's being chambered and shot in 30.06 based smaller bores. There are a couple differences.
Since it happens mostly in bolt actions, often the guns don't come apart. There are no dramatic photos to post.
I will go as far as to say there may also be an attitude difference. If you search out videos of people doing stupid stuff and getting injured with tannerite, it sure seems like there are not a lot of bolt actions being used.
It's a different generation of shooters out there coming up. They video and post themselves eating tidepods, setting themselves on fire and licking toilet seats. Why not glorify blowing up a firearm when you make an actual mistake?
The percentage of AR's blown up by chambering a 300 BLK in a 223/556 may actually be less than some of the other combinations out there, but as pointed out because of sheer numbers involved, seems like the only combination that it happens with.
I don't remember ever hearing of 330 Whisper or 300-221's blowing up 223's, What's the deal with this new 300 Blackout cartridge?
Those are some of the reasons I think blaming the cartridge is the wrong way to go.
I have been known to shoot an AR at a public range and hate being lumped in with the idiot black rifle crowd, that even many here complain about, but mom warned me about running with the wrong crowd and bring guilty by association.
That's not fair either.
I only suggest/recommend a 300BO to someone if they are an experienced AR15 shooter and will recognize the inherent risk. Also, they must be experienced enough to immediately differentiate a 5.56 cartridge and 300BO.
It is when 6x45 comes into play that even experienced shooters may not make the distinction. I went with an AI case to help easily differentiate for this one... Belt & Suspenders!!!
My gunsmith has a barrel with 5-7 bullets stacked up in it like train cars. It looks great with half the barrel machined away ... nice cross-sectional view of some idiot's marksmanship.
It is when 6x45 comes into play that even experienced shooters may not make the distinction. I went with an AI case to help easily differentiate for this one... Belt & Suspenders!!!
My gunsmith has a barrel with 5-7 bullets stacked up in it like train cars. It looks great with half the barrel machined away ... nice cross-sectional view of some idiot's marksmanship.
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GotRDid
Gold $$ Contributor
As a follow up to our efforts to prepare for the Youth Hunt, Caden took a yearling Doe at about 40-43 yds in the timber. His first Deer and 8 yrs old and we are so proud. Paul is Caden’s Grandfather and the first Sniper I ever trained after my All Skills Firearms Instructor certification was complete (that was a long 18 months). Paul and I are both retired but are still close. Paul’s Father, Joe, passed away 2 months ago and Joe left me his Hunting rifle knowing I would take it (and Joe) hunting for the rest of my years. When the time comes, it will be given back to Caden if he sticks with hunting.
Thank You for letting me share.
GotRDid.
dellet
Gold $$ Contributor
GotRDid
Gold $$ Contributor
Larry Koch
Silver $$ Contributor
Really the list is endless. There are so many more cartridge today than just 30 years ago. One should be aware at all times..300 Blackout. Not such a good design. We see one of these blow-ups on the web every couple of months because the .300 BLK will chamber in typical .223 Rem barrels.
View attachment 1284429
.300 Blackout Fired in .223 Rem — Mistake Is Disasterous « Daily Bulletin
Photos and Facebook post by Tactical Rifle Shooters Yet another .300 Blackout disaster. Unfortunately, that .300 Blackout cartridge can fit in a .223 Rem chamber. Shooting a .308-caliber bullet in .223 bore is a recipe for disaster. <img src=https://accurateshooter.
View attachment 1284430
drop_point
Silver $$ Contributor
For one, people leave magazines loaded. Since both rounds use the same magazine, it is easy to grab the wrong one.
Anytime the wrong round ends up in the chamber, its an operator error. Its not as those pesky .300 Blackout rounds go around looking for vulnerable .223 Remington chambers to climb into.
The .300 Blackout is an excellent round that produces excellent energy out of short barrels and they work wonderful as a suppressed round. Nothing else really does quite the job, but you do have to be careful and pay attention because some, not all but some, .223 Rem chambers will accept the round with certain bullets loaded or loaded improperly. I do believe most of the incidents I've read about were handloaded OR factory loaded with a projectile not normally seen in the round.
What I do is use the .300 Blackout specific magazines and color fill the ".300" with a silver sharpie. I always try to also use a different color magazine if taking out both calibers in a single outing (such as tan 5.56 magazines and black .300 Blackout magazines labeled clearly "300"). Also, never leave a .300 Blackout magazine loaded.
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