[Brandons18wheeler]

Hello. I am new to this forum. I have an AR platform with 3 different upper assemblies: 5.56, 6.8 spc and .300 AAC blackout.

I made a very stupid mistake today. My 5.56 and 6.8spc uppers look almost identical with a tan/black mix of color. I went to the range intending to sight in the 5.56, but accidentally mounted the 6.8spc upper. My mag was loaded with 5.56 rounds. I fired a round of 5.56 through the 6.8spc and the spent casing failed to eject, causing the rifle to jam. When I finally was able to push the spent casing out with a rod from the muzzle end, I saw that the casing was fractured with a hole blown out of it.

I am going to take everything apart, clean it and probably take it to a gunsmith for examination. My question to the forum is this. Has anyone ever made this stupid mistake, and if so, did it permanently ruin your rifle? What damage would you expect from firing a 5.56 round through your 6.8 spc?

Thank you for any insight you can offer.

 

[greentick]

It's happened before, on here somewhere...

 

[Brandons18wheeler]

It's happened before, on here somewhere...

Thanks greentick! I searched and found the thread where EXACTLY the same thing happened back in 2013! The description of the burst casing was exactly what mine looks like. I guess I will take someone's advice and get the barrel mag particle inspected.

Wrong ammo fired in a 6,8!!!!

Guys, A buddy reported an accident to me a couple of days ago. He popped a magazine into his 16" flat top and let the bolt fly. He had to juggle things around a little but got the bolt to fully close. When he pulled the trigger ... there was a weird sound and WAY TOO MUCH smoke around the...

www.68forums.com

 

[Woodstock]

A lot of old names in that thread. I would not worry about having it inspected if it were me. As noted in that other thread, it is not a problem that would create a high pressure problem. I doubt it did any damage. Clean it up and shoot it would be my thoughts. Good luck finding someone to do a mag particle inspection anyway.

 

[Brandons18wheeler]

A lot of old names in that thread. I would not worry about having it inspected if it were me. As noted in that other thread, it is not a problem that would create a high pressure problem. I doubt it did any damage. Clean it up and shoot it would be my thoughts. Good luck finding someone to do a mag particle inspection anyway.

Thanks Woodstock. I'll take your advice - clean it up, take it back out and shoot it. No mag particle inspection.
I hate learning lessons the hard way. Embarrassing. I'm going to color code both rifles and the mags. Right now they look nearly identical.

 

[earlytom]

Welcome to the 68.

 

[Brandons18wheeler]

Welcome to the 68.

Thanks EarlyTom! Seems like a good group with a lot of collective wisdom!

 

[Blowout]

Might pick yourself up an ejection port cover with 6.8SPC written on it. I just bought and installed one on a new 6.8 build. Probably will need to remove the handguard to install it. I have one rifle where it wasn't necessary.

I also put them on the other calibers I've got. Too easy to make the mistake your referring to.

 

[Strawdawg]

I have done the same. Really helps.

 

[Brandons18wheeler]

Might pick yourself up an ejection port cover with 6.8SPC written on it. I just bought and installed one on a new 6.8 build. Probably will need to remove the handguard to install it. I have one rifle where it wasn't necessary.

I also put them on the other calibers I've got. Too easy to make the mistake your referring to.

Thanks Blowout & Strawdog. Great suggestion. I will do that.

 

[Xman]

Just don't make the mistake of shooting 300 BO in your 5.56

 

[Brandons18wheeler]

Just don't make the mistake of shooting 300 BO in your 5.56

Yes, Xman, that would be much worse. It's fortunate that the 5.56 was smaller than the 6.8 spc barrel. That mistake was bad enough. Thanks...

 

[SMH]

Just don't make the mistake of shooting 300 BO in your 5.56

LOL! It can and will happen. That's not my only gripe against 300 Body Odor but it's a biggie!

 

[Brandons18wheeler]

LOL! It can and will happen. That's not my only gripe against 300 Body Odor but it's a biggie!

"...300 Body Odor..." 😂😂🤣🤣

 

[elvisfranks2804]

I posted a picture of a .223 case that was fired in a 6.8 by my nephew on here before . It looked like a pregnant guppy . As others have said other than possibly needing a good cleaning little chance of damage because the bullet is small for bore which keeps pressure low . This prompted me to color coordinate my ARs and magazines . 6.8s are all black . 5.56 /.223 are green and Bo is desert tan .

 

[Brandons18wheeler]

I posted a picture of a .223 case that was fired in a 6.8 by my nephew on here before . It looked like a pregnant guppy . As others have said other than possibly needing a good cleaning little chance of damage because the bullet is small for bore which keeps pressure low . This prompted me to color coordinate my ARs and magazines . 6.8s are all black . 5.56 /.223 are green and Bo is desert tan .

Thanks Elvis. Color differentiation is a good idea. Especially between my 5.56 and the 6.8 spc, which are both dressed in tan and look practically identical. Lots of good ideas on this thread that I'll definitely be using. Once I'm finished and I take the 6.8 out to the range again (hopefully this week), I'll report back here on everything I did.

Here's a picture of the 5.56 I fired through the 6.8 upper. It tried to swell up too, but it burst before it reached pregnant guppy status. I had to push it out of the chamber with a cleaning rod.

 

[Blowout]

I posted a picture of a .223 case that was fired in a 6.8 by my nephew on here before . It looked like a pregnant guppy . As others have said other than possibly needing a good cleaning little chance of damage because the bullet is small for bore which keeps pressure low . This prompted me to color coordinate my ARs and magazines . 6.8s are all black . 5.56 /.223 are green and Bo is desert tan .

Good point on also marking magazines. Be safe and use a rubber!

 

[Brandons18wheeler]

Good point on also marking magazines. Be safe and use a rubber!

😂😂🤣

 

[Ten Rounder]

Here's a picture of the 5.56 I fired through the 6.8 upper. It tried to swell up too, but it burst before it reached pregnant guppy status. I had to push it out of the chamber with a cleaning rod.
View attachment 78285

You should anneal your cases before you try to fire forming again. Just sayin'.

 

[Brandons18wheeler]

You should anneal your cases before you try to fire forming again. Just sayin'.

Ten Rounder, anneal for reloading?