Alright guys. First post here at m4carbine so please take it easy on me.
I’ve been having major issue with key holing at surprisingly close distances. This picture was taken today and all rounds were fired at about 25 yards.
This target was shot with Federal and Winchester brass and Monarch steel and brass cased ammo. As you can see there are some normal holes from bullet impact but lots of holes indicating tumbling. I believe I have determined that this issue isn’t related to a particular brand or type of ammo but seems to happen to all brands.
I will detail my AR’s setup:
Dpms upper, lower, and barrel (barrel has probably 5000+ rounds)
Spikes Tactical BCG
Commercial buffer tube with magpul CRT stock
JP Enterprises captured buffer/spring assembly
Midwest Industries 15" Gen2 SS hand guard
Smith Vortex FHMB
Troy micro gas block
Geissele SSA trigger group
Daniel Defense front and rear fixed iron sights
I know I gave more details than are necessary but if anyone has any idea why I’m having this key holing issue, any help would be greatly appreciated
Agreed. Time to invest in a new barrel. I don’t know your gunsmithing abilities, but wether you have someone do it or you DIY, get a good quality proven barrel.
What kind of use has this thing seen? I know it’s a DPMS but 5000+ seems low.
Not what you asked but looking at your set up, the new BCM ELW KMR uppers would make a sweet replacement.
Seen lots of rounds, usually and a decent rate of fire. I also hadn’t thought about a new upper. Would that possible effect it or would it just be nice to go with a new barrel.
IIRC, the spikes barrels are sourced from FN. I have a couple, never measured groups with it but it was more than suitable. There are better barrels out there, depends on your budget. BCM has gotten my money more than a few times, good people good products. There are a ton of good barrels out there, we are living in the golden age of AR’s. Just do your research. Spend your money well. And search this site. Tons of info from knowledgeable folks.
another vote for bcm here, on my next build i am going with a hammer forged bcm. if you had the fund you could always go with a bcm upper and bcg and you would be good to go for a very very long time. check out the bcm filthy 14.
edit: also did you check your flash hider to make sure it didn’t loosen on you?
“the Brown Bear and Wolf carbines exhibited significant accuracy loss by the 6,000 round mark. It is quite possible that this first started occurring earlier than 6,000 rounds, because groups at 4,000 were well within standards of 5MOA or less, while some shots at 6,000 “keyholed,” or impacted the target sideways.”
One thought before you go replacing the barrel would be to clean it very thoroughly. It may very well be shot out at 5K rds - but, it may not. I would recommend busting out some serious cleaners (ie Barnes CR-10) before you sign it off and get a new barrel. For very heavily fouled (read copper-fouled) barrels this may occasionally work wonders. I had a surplus rifle that shot like poo until I burnt through a serious pile of patches and CR-10. It was so fouled the patches came out complete blue from the accumulated copper fouling.
If not, I am sure any one of the quality barrel/bolt makers listed above will be able to provide you with a satisfactory replacement.
Is was a thought of mine too but I have cleaned and cleaned and cleaned. Blue patches just like you described.
I have shot a good but of steel cased ammo and coupled with the high rate of fire and round count I have a good feeling that the barrel may be shot. Gonna look into a CHF barrel from one of the numerous companies that manufactures and/or sells them. Thanks for everyone’s help!
