Cleaning really does help you find problems

[JAFO]

So I was cleaning my AR9 in preparation for a Steel Challenge match tomorrow. I found both gas key bolts were loose, which allowed the key to move under recoil and the front lower edge of the key was peened into a 2mm lip that extended underneath. The metal is pretty soft, so I filed it flat and used blue Loctite (don't have any red) on the bolts. I marked them with a paint pen, but I'm not sure if that will stay on. 

 

I also found that the firing pin was broken. This was the original black NFA pin that came with my bolt. It had ~2400 rounds, plus some dry firing on it. It broke at the first shoulder. 

 

 

I replaced the pin and spring with a new silver NFA pin that has a different transition on that shoulder. 

 

 

I guess it does pay to clean things once and a while. 

[HoMiE]

Make sure you don’t get loctite in the firing pin channel. Don’t ask me how I know.

[stick]

Cleaning my PCC last week, I noticed my firing pin was bent.  Since I have 3 extra, I replaced it.

[Les Snyder]

round the strike end of your firing pin, so the hammer strikes closer to the center.. my black pin broke at around 400, the Colt rounded replacement is over 7000

[Nathanb]

Funny enough I found my mpx had a broken bolt carrier and bolt during cleaning 

[DesertTortoise]

That's what happens when you remove all the oil and carbon holding everything together

[L9X25]

This is just a hoax perpetuated by the clean freaks, I will continue my once a year cleaning schedule as usual.

[JAFO]

7 hours ago, Les Snyder said:

round the strike end of your firing pin, so the hammer strikes closer to the center.. my black pin broke at around 400, the Colt rounded replacement is over 7000

 

Interestingly, there is no indication that the original pin was being struck off-center. At least, the head is not deformed at all. 

 

[Les Snyder]

JAFO... my pin was mushrooming around the edge... my thinking was that the hammer was inducing an off center impact that could impose lateral stresses on the reduced diameter section, especially at the point where it was narrowed (and broke)....it may have been just the difference in metallurgy between the two pins... I will continue to round my pins... regards

[cecil]

when I was younger my dad use to let me use his shotgun & rifle to hunt... on one condition... "to clean & oil  it when I got home'  . that lesson I still carry out.. I clean my guns EVERYTIME I shoot one... 

[Roy T]

L9X25

When you do your annual let me know and I will bring my stuff over and we can toss em in the dishwasher together

[MemphisMechanic]

1 hour ago, cecil said:

when I was younger my dad use to let me use his shotgun & rifle to hunt... on one condition... "to clean & oil  it when I got home'  . that lesson I still carry out.. I clean my guns EVERYTIME I shoot one... 

 

That’s disgusting. You should really quit that.

 

 

[JAFO]

20 hours ago, Les Snyder said:

JAFO... my pin was mushrooming around the edge... my thinking was that the hammer was inducing an off center impact that could impose lateral stresses on the reduced diameter section, especially at the point where it was narrowed (and broke)....it may have been just the difference in metallurgy between the two pins... I will continue to round my pins... regards

 

I had checked the pin head a few months ago when I was reading about deformed pins and rounding the ends.  It seems that, with so many combinations of bolts, triggers, etc, every setup is slightly different.  I'll keep an eye on the new pin and round it if it looks like it's getting hit off-center.  But for now, my setup seems to smack it pretty close to flat.

[jtrump]

I would clean my gun less often but my JP barrel eats lead bullets,  after just one match pretty much half my comp is blocked.

[JAFO]

3 hours ago, jtrump said:

I would clean my gun less often but my JP barrel eats lead bullets,  after just one match pretty much half my comp is blocked.

 

I had that problem at first, when I was using my normal pistol load.  I backed off the powder 0.4gr and I get a lot less buildup now.

[jtrump]

3 hours ago, JAFO said:

 

I had that problem at first, when I was using my normal pistol load.  I backed off the powder 0.4gr and I get a lot less buildup now.

While were on the topic,  I just went and cleaned my gun where I have access to a parts washer, and taaaadaaaa,  my firing pin was broken..   No idea how long it's been that way haha.

 

[JAFO]

Welcome to the club. 

 

I now view this broken firing pin phenomenon much like being DQ'd.  It's not really "if" it happens, but when.

[jtrump]

1 hour ago, JAFO said:

Welcome to the club. 

 

I now view this broken firing pin phenomenon much like being DQ'd.  It's not really "if" it happens, but when.

Don't jinx me on the DQ part on on a streak!