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beastie050
11-25-2011, 9:53 PM
My AR-15 has about 600 rounds through it. Today at the range it started double firing. I took a look at it, and the hammer pin was broken in half. Has anyone else had this problem? Are there higher quality pins to use? It was a DPMS lower parts kit

nitroxdiver
11-25-2011, 10:19 PM
Heres a recent thread of another dpms pin breaking.
http://www.calguns.net/calgunforum/showthread.php?t=501822

Some suggestions. Call dpms and ask for a replacement, order some kns pins, upgrade your complete lower parts kit with a Daniel Defense kit or the like.

Take care

joelogic
11-25-2011, 11:06 PM
Seems common with DPMS, maybe its their heat treating. People usually recommend kns anti-rotation pins but maybe just a better LPK.

muffpotter
11-26-2011, 9:58 AM
ya mine snapped last week too. also dpms

jimster716
11-26-2011, 10:49 AM
Yeap, the thread nitroxdriver is referring to is mine. I emailed them and they were sending out a new pin. Kinda crappy but the more people contact DPMS the more likely they'll have to assess their supplier for the pin.

Question, have any of you with broken pins dry fired with the upper and lower separated? I'm wondering if the impact from dry firing would cause the hammer pin to snap.

beastie050
11-26-2011, 10:51 AM
mine has never been dry fired with the upper/lower separated.

GMG
11-26-2011, 11:04 AM
Yeap, the thread nitroxdriver is referring to is mine. I emailed them and they were sending out a new pin. Kinda crappy but the more people contact DPMS the more likely they'll have to assess their supplier for the pin.

Question, have any of you with broken pins dry fired with the upper and lower separated? I'm wondering if the impact from dry firing would cause the hammer pin to snap.

There's a good chance the hammer may damage the lower if dry fired with the upper and lower seperated.;)

jimster716
11-26-2011, 11:12 AM
Yeah I read the thread on the dry firing. I have to admit I've done that two or three times trying to understand the workings of the AR. :-)

dieselpower
11-26-2011, 2:49 PM
happened to me on a Colt..its a non-issue if you carry a spare pin or two. Just push the new one into place while pushing the old one out.

luckystrike
11-26-2011, 3:31 PM
Happens once in awhile. Spare lower parts are good to have onhand

WDE91
11-26-2011, 5:07 PM
sorry about your hammer pin but I would love to see some pictures of your Evo

beastie050
11-26-2011, 5:10 PM
sorry about your hammer pin but I would love to see some pictures of your Evo

https://fbcdn-sphotos-a.akamaihd.net/photos-ak-snc1/v4598/112/26/675094166/n675094166_2642459_3717586.jpg

https://fbcdn-sphotos-a.akamaihd.net/hphotos-ak-ash4/285435_10150400652889167_675094166_10514159_704312 3_n.jpg

WDE91
11-26-2011, 7:11 PM
exterior looks pretty stock, the brakes OE?
suspension looks about at stock height

What all have you done to it?

beastie050
01-17-2012, 11:12 AM
exterior looks pretty stock, the brakes OE?
suspension looks about at stock height

What all have you done to it?

standard brembo brakes, standard bilstein suspension. I just did a downpipe, high flow cat (used to be a test pipe), Greddy Titanium Exhaust, and a Works flash. Fairly stock.

beastie050
01-17-2012, 11:12 AM
DPMS pin broke AGAIN! maybe 500 rounds later, wtf :) I bought a JP one this time, we'll see if it lasts longer.

green grunt
01-17-2012, 11:14 AM
KNS pins work great.

gun toting monkeyboy
01-17-2012, 11:17 AM
Damn. I have never had one break on me, DPMS or otherwise. I have spares, but I didn't think this was something that broke all that often.

beastie050
01-17-2012, 11:19 AM
Damn. I have never had one break on me, DPMS or otherwise. I have spares, but I didn't think this was something that broke all that often.

yeah me either, could it be too much gas I wonder? maybe it putting the bolt back too hard.

russ69
01-17-2012, 11:30 AM
Sounds like an improper heat treat. Pins are small so it's easy to "over cook" them, that makes them very hard but brittle.

beastie050
01-17-2012, 11:31 AM
Sounds like an improper heat treat. Pins are small so it's easy to "over cook" them, that makes them very hard but brittle.

on two different pins? bummer

FeuerFrei
01-17-2012, 11:32 AM
DPMS pin broke AGAIN! maybe 500 rounds later, wtf :) I bought a JP one this time, we'll see if it lasts longer.


If the lower's pin holes are off (out of spec) the pin will wiggle and eventually break. KNS pins will band aid the symptum but not cure the problem.
Are they breaking at the J spring notch?

beastie050
01-17-2012, 11:33 AM
If the lower's pin holes are off (out of spec) the pin will wiggle and eventually break. KNS pins will band aid the symptum but not cure the problem.
Are they breaking at the J spring notch?

Yeah right at the notch

duggan
01-17-2012, 12:02 PM
Dry firing shouldn't do any harm (upper and lower together) it's part of the functions check after reassembly.

crazychinaman
01-17-2012, 2:00 PM
Yes, I agree with everybody .Use KNS pins.I have broken before in the past.I always have a complete lower parts kit on hand.

supersonic
01-17-2012, 2:08 PM
There's a good chance the hammer may damage the lower if dry fired with the upper and lower seperated.;)

......so make sure to catch the hammer with your thumb/finger before it can strike the rear of the magwell. ;)