Robinson Arms XCR. 223 - Bolt carrier blew up **UPDATE**

To me, it looks like pieces of brass in the chamber. Did you take these pieces out and examine them? Shouldn't be hard to tell brass from what should be burned up pieces of corn cob or walnut. That is, unless you're tumbling in brass media, which would be new.

Also, from the look of the cartridge, there was no way that thing was fired in battery. When you fire in battery you don't see cartridges all twisted up like that. Over pressured cartridges will blow off the back end of the cartridge and leave the side walls, and throat of the cartridge stuck in the barrel. All the brass you get to see is the very bottom, and more often than not it'll be either long gone or stuck in the extractor (or what's left of it), the rest of the case stays in the barrel.

Also, look at the primer. That thing appears as round as it was when it was new. If this was an over pressure problem, the primer would typically be flat (there are rare exceptions).

Frankly, this shows some pretty glaring signs of an out of battery firing.

Do you full length resize your brass? Also was this brass fired in your gun prior to reloading, or is it 'from parts unknown'? Lastly, did you get the ka-boom after you pulled the trigger, or after the action cycled? I'm not familiar with the XCR, will the firing pin more forward when the action is open?
 
What causes it to fire out of battery?

I got a kaboom when i pulled the trigger , only a bit of the cartridge was sticking out, I used a ram rod to dislodge the cartridge from muzzle end. I have a picture of how it all looked.

I do full length resize them, never had an issue with this before.
 
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To me, it looks like pieces of brass in the chamber. Did you take these pieces out and examine them? Shouldn't be hard to tell brass from what should be burned up pieces of corn cob or walnut. That is, unless you're tumbling in brass media, which would be new.

Also, from the look of the cartridge, there was no way that thing was fired in battery. When you fire in battery you don't see cartridges all twisted up like that. Over pressured cartridges will blow off the back end of the cartridge and leave the side walls, and throat of the cartridge stuck in the barrel. All the brass you get to see is the very bottom, and more often than not it'll be either long gone or stuck in the extractor (or what's left of it), the rest of the case stays in the barrel.

Also, look at the primer. That thing appears as round as it was when it was new. If this was an over pressure problem, the primer would typically be flat (there are rare exceptions).

Frankly, this shows some pretty glaring signs of an out of battery firing.

Do you full length resize your brass? Also was this brass fired in your gun prior to reloading, or is it 'from parts unknown'? Lastly, did you get the ka-boom after you pulled the trigger, or after the action cycled? I'm not familiar with the XCR, will the firing pin more forward when the action is open?

Definitely looks like brass in the chamber, media in the case wouldnt do this. Out of battery firing, or something blocking the barrel/chamber/ wrong barrel/chamber for bolt/cartridge? What does the chamber and barrel look like, did the bullet leave the barrel? Was it a double/slam fire?
EDIT: How hard was it to remove the barrel bolt? could the barrel have slid forward as the round was being chambered and fired?
 
Ya, it musta blown out the back of the casing, can't be more than $200 for new parts. (here's to hoping) It was just a louder bang, other than that some smoke out of the receiver where you don;t usually see smoke, wasn't scary. My wife was with me shooting, glad she wasn't behind it. Her reaction "Huh, that can't be good"

Show me where you can buy a barrel and bolt for $200, I'd buy 10. That barrel is toast.
What does the trigger group look like?
 
Barrel is fine, it came out as it normally does. Yes the bullet left the barrel as i previously stated. After looking at everything closely , just the bolt and bolt carrier are damaged.
 
Forgive me for my ignorance, but can you see damage to the barrel? I've been lucky with my XCR, but it would be good for me to know what to look for in case something does happen.
 
barrel.jpg



Is that not a giant gouge out of the chamber I am seeing
 
From looking at my bolt and carrier, it appears that the hammer should not be able strike the firing pin unless the bolt is rotated and seated in the carrier. How can the bolt rotate forward without being seated in the barrel Lugs so the hammer can hit the firing pin?
IMG_0481.jpg

IMG_0475.jpg
 
Scary stuff. Glad your OK
Looking at the damage to your bolt and carrier, I'm curious as to the condition of the OP rod and trigger? Any Pics? Never seen or heard anything like this with the XCR. Any chance the barrel slid forward? was the barrel bolt loose when you took it apart?
Also have to ask how many round down the pipe, did you buy it new, were those hand loads? Size, weight of rnd, powder?
I think I would be contacting rob arms or wolverine before even considering rebuilding.
 
I, too, would make darn sure the reamining parts are servicable before buying any replacement parts. There was a lot of violence released there. The rifle may well be rebuildable form a cost effective standpoint, but it would be best to find out exactly what the situation is.

I have seen failures resulting from gross catastrophic case failure when the actiion is correctly locked. The casehead flows, pressure often blows out the extractor, this being the weak point. This didn't happen in this incident.
 
What causes it to fire out of battery?

I got a kaboom when i pulled the trigger , only a bit of the cartridge was sticking out, I used a ram rod to dislodge the cartridge from muzzle end. I have a picture of how it all looked.
I do full length resize them, never had an issue with this before.

Just for clarification the case was still in the chamber = not out of battery when it fired?

I'd like to see the pic before you dislodged the case.

CC
 
What powder were you reloading with?
It strikes me that you would need a decent amount of tumbling media stuck in the case to over pressure the round like that.
I don't know if you reload for pistol as well, but is there any chance you had the wrong type of powder still in the thrower when you added the rifle powder?
I would pull some more of the reloads and check powder weight, see if there is media in the cases.
You don't want to make this mistake twice.
I've known guys who had to pull a lot of rounds after trying to blow handguns up with the wrong charge weight.
 
Is it range brass or do you know approx. how many times it's been fired? Other than the obvious mangling of the case, it seems to have the split starting at the usual area for a case head separation. Any bright rings on the case near the base that you can recall when you reloaded it?

There is also a small chance that the bolt/carrier had a defect, but that wouldn't be my first guess since you're reloading (that's usually the first culprit).
 
OK I will go through in detail everything that was asked.

The case was maybe on it's second firing, unfortunately looking at the headstamp it's that brass i try to not use FC headstamped because it is shorter brass 1.140-.1.145, never had an isue before though.
62 grain projectile
2.225 OAL
25 Grains of BLC-2

I only have ever run through BLC-2 through my Dillon 650

Again NO damage to operating rod or trigger, barrel has nothing wrong with it upon inspection, i can drop cartridges in and they fall out fine after fitting all the way in. The Extractor DID blow off, so that lend to believe it was in battery. for some reason the energy blew out the back of the case, however bullet went downrange. Barrel did not slide forward it was snug and in place. I believe i had a case failure at this point.

I added new pics to the first page.
 
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After looking at the pictures and reading the aftermath, I'm thinking the case head separation caused it.
I'm not 100% familiar with XCRs (so I may be off) but it seems like: round chambered, bolt locked, round fired, as carrier moved back to unlock the bolt, the case head failed causing gas to exit to the rear of the chamber, wrecking the extractor, shoving the bolt harder than normal into the carrier which caused the cam lug to impact too hard splitting the carrier.

Added: since the cam slot on the XCR is open ended (unlike closed on an AR carrier), I think it had a tendency to just peel like a banana since nothing was holding the open end together.
 
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