BCL 102 catastrophic failure
- Thread starter slash547
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I have seen a number of times now where guys lose primers and find them stuck to the inside of their chamber. Funny things happen when you are loading way over max pressure. It would be no different during a case head separation event. Lucky the OP didn't find that brass inside himself or someone standing close to him. Glad no one got hurt! This looks like text book case head separation. Always check headspace when installing new parts, ALWAYS.
If OP measures headspace with a comparator on the brass that wasn't trashed, and compares to old brass fired and not sized through the gun before mods, it would give a solid answer if headspace was to blame.
If OP measures headspace with a comparator on the brass that wasn't trashed, and compares to old brass fired and not sized through the gun before mods, it would give a solid answer if headspace was to blame.
Lugs look intact. Brass found as seen in pic, on the ground. The BCG was jammed into the buffer tube and you can see the imprint of the ejector pin on the case head.
I too am baffled why the end of the case is crimped in???
Load data states 42 grn start and never exceed 46. I loaded all at 44 and have had good success to date. All spent cases have the primers in them and all cases are accounted for. Thanks for your thoughts though, appreciate it.
LordEvilPepper
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- Location
- Under a rusty barge in BC
If you eliminate the case the next thing i would be checking is timing on the gun and burrs/ridges in the chamber
Out of battery is only possible in very tight proximity to being in battery on this design.. and only if #### is ####ed up.
You were getting stove pipes itz means not enough force, or.. The gun is try to extract before the case has contracted fully causing it to stick... check the fired cases rims for damage by the extractor. And possible horizontal cracks in the case wall (when you stand the cases on its head).. if the rims look "pulled back" or bent back or there is cracks running around the diameters of the case thats probably part of the issue... this can cause the case to be ripped apart leaving the neck and shoulder in the chamber.... Causing a partial out of battery on the next round.. That still allows firing to occur on a sloppy gun. .... Which would cause this....
Sometimes a rough cut chamber can do the same thing.... Had that issue on a mini 14
Out of battery is only possible in very tight proximity to being in battery on this design.. and only if #### is ####ed up.
You were getting stove pipes itz means not enough force, or.. The gun is try to extract before the case has contracted fully causing it to stick... check the fired cases rims for damage by the extractor. And possible horizontal cracks in the case wall (when you stand the cases on its head).. if the rims look "pulled back" or bent back or there is cracks running around the diameters of the case thats probably part of the issue... this can cause the case to be ripped apart leaving the neck and shoulder in the chamber.... Causing a partial out of battery on the next round.. That still allows firing to occur on a sloppy gun. .... Which would cause this....
Sometimes a rough cut chamber can do the same thing.... Had that issue on a mini 14
we are thinking along similar lines on this but he stated all the other extracted brass was accounted for so it leaves me very stumped....
I don't understand these rifles to the depths many of you other guys do so it's gonna be interesting to me if this can be diagnosed
Hornady Interlock 165 gr SP,#3040
Stove pipes is a known issue with the BCL and is part of their current recall. They sent me a brand new BCG when I pushed it and got John at Marstar involved since BCL was not communicating.
https://www.huntinggearguy.com/rifle-reviews/bcl102-review/
https://blackcreeklabs.com/recall-notice/
LordEvilPepper
CGN Ultra frequent flyer
- Location
- Under a rusty barge in BC
which would bring me bacb to think this is some sort of a brass stub out/ obstruction crimping/ over pressure issue
looking at the cases the ejection mouth ding is very real. if you were to load one of those up and was a bit rough after resize with a little crinkle that could cause problems. one of those unfired rounds looks like it has this going on.
if that was getting jammed in and folding over on the side of the cases it could result in the same thing... hard ejections and crimp like over pressure scenario.
your kaboom case looks like it is missing the neck is it still in the chamber?
since the lugs are still in, and the gun is more or less "intact" for a structural point let's look at the reloads
What is your process in exact order for reloading? do you crimp or not? what kinds of dies are you using (it matters for crimping and trying to diagnose).
Something like an over charge seems unlikely given your previous response but I have a couple theories on overall process here that would probably narrow it down.
key points
-Do you trim before or after sizing?
-how picky are you with CASE OAL? if its under good enough. Or do you trim al the same every time ? (this question matters for certain brands of dies, i learned that when it would buckle/bulge cases with as little as 3 thou case OAL difference) using .30 carbine.
-do you crimp onto the canlour or just were it falls when you seat to desire depth.
do you seat with a competition die set or with a basic one (lead nose can make basic which seat directly off the bullet nose ones seat at different depths causing a much higher pressure especially with crimp)
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Well, we most likely found the chambering problem. You should not use soft points in an AR10. The action and feed ramps during chambering will chew the noses off and cause all sorts of issues. I still would point to case head separation as the cause of failure. Look how the case is blown out at the base. 44grs could definitely do it, especially if you are not crimping or know the new headspace dimension after changing BCG. Or if a piece of the bullet nose ripped off and held the case back in the chamber. All sorts of things could of caused it, but primarily looks like ICHS.
Good cleaning
One Shot case lube
Lee turret press full length sizer, manual powder measure and pour, bullet seat to the bullet interlock ring, final crimp
LordEvilPepper
CGN Ultra frequent flyer
- Location
- Under a rusty barge in BC
if your using lee crimping die... good that eliminates that (one of the few things lee makes that I think is best in the field) its the hornady dies that will cause ridiculous over crimps with varying OAL case leangth.
if your crimping on the canalour.. perfect, its has more crimping forgiveness.
get a caliper on the unfired cases (rim to base) see if there in spec.
if your crimping on the canalour.. perfect, its has more crimping forgiveness.
get a caliper on the unfired cases (rim to base) see if there in spec.
Did it. All at or below 2.015 except two, 2.019 and 2.024
LordEvilPepper
CGN Ultra frequent flyer
- Location
- Under a rusty barge in BC
9 thou overmax is not good,
2.026 was what the case measured that caused my rugger GSS to kaboom...
think we found your problem
always trim, and always after resizing the case
I always set mine to 2.005 on my redding trimmer, then after getting out of precision reloading i just went to the lee system (go go drill adapter) and i thick it trims at 2.000
2.026 was what the case measured that caused my rugger GSS to kaboom...
think we found your problem
always trim, and always after resizing the case
I always set mine to 2.005 on my redding trimmer, then after getting out of precision reloading i just went to the lee system (go go drill adapter) and i thick it trims at 2.000
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Have you taken the handguard off and looked at the barrel, deformation of any kind
This is something I was going to bring up earlier. Magpul makes it seem like is is very important to use the right buffer and/or spacer. I'm not sure how it could lead to an issue like this but who knows..?
