Just picked up a gun through equipment exchange and I keep breaking extractor pins.

Rifle specs:

Oly stop sign lower
Wilson SS 16" NATO 8:1barrel
Not sure about upper - A2 with no markings that I can find.
It had an M16 bolt carrier, I've replaced it with a new AR bolt carrier from Model 1 Sales.
I rebuilt the bolt with new 1 piece gas ring, ejector assembly and extractor assembly.
I replaced original trigger with a RRA NM.

The rifle shoots fine. I'm just on my 2nd extractor pin in less than 300 rounds.

I don't think I'm using Ammo that's to hot.

I've run a few types through it since I got the gun:
Olympic 5.56 .62 Grain - Ran like crap
Top of the line Federal .223 .55 Grain - not much better

Cleaned the gas tube and rebuilt the bolt etc.
Then:
Wolf Polymer coated .55 Grain M193
Lake City .55 grain XM193 (OK maybe this stuff's is a little hot).

While cleaning it today I noticed I had another broken extractor pin! I'm honestly not sure if the gun came with a broken pin or not, but it had one when I took down the gun to clean the gas tube and install the new parts.

The seller has been great and has offered to reimburse me for any parts, but I'm not worried about that...What can cause broken extractor pins and how do I fix it????

Thanks for you help,

Jon

Increased bolt thrust due to excessive headspace can cause the problem you are having. For safeties' sake and peace of mind check the HS with gauges. Charles the Gunsmith.  

Quoted: Only way that you should be snapping extractor pins is if, 1. The pins where not heat-treated correctly, and the extractor pins are too brittle. 2. The extractor is making contact on the barrel extension/lug during lock/unlock and is causing impact shearing. Take a look at the outer edges of the extractor; there should be no wear from any kind of contact on the other edges, including the front edge of it against the barrel shoulder inside the barrel extension.

Improper heat treating of the pin sounds about right to me. The original pin might have been broken when I got the rifle, but the 2nd one (from Model 1 sales) didn't look right to begin with. I've installed another new pin from a Bushmaster field repair kit I just picked up. We'll see what happens...

As far as contact with barrel lug goes, I don't THINK that's the problem, but I am very new to the AR platform.
Inspecting the OLD extractor, i found rather significant wear (although not excessive) on the sides of the extractor, but nothing major on the lead edge of the extractor where it meets the barrel lugs.

I've attached a couple photos (I hope). Let me know what you think... Just trying to learn a little.

Jon

Photos:
Had to go URL method for now, until I figure how to link from Yahoo.

Pic 1

Pic 2

That brings up a few questions for me. I've wanted to get a set of gauges but I'm confused.

Which caliber\ set? There are so many different yet similar gauges out there. I just want a good inexpensive set of gauges (Go, No-Go, & Field). Do I really need a Field gauge?

My current barrel is a 5.56 NATO. I'm waiting a RRA upper with their standard Wilson HBAR, which is a 223/5.56 NATO Chamber??? I assume that gauges for .223 SAAMI will not work. There's just a LOT of contradictory info out there, so I'm asking the question - what HS gauges do you guys recommend for the AR?

thanks from a grateful newb,

Jon

Quoted: Do I really need a Field gauge?

I feel that if you only own one gauge that it should be a field.

www.brownells.com/aspx/NS/store/ProductDetail.aspx?p=6646&title=5.56mm+(.223)+HEADSPACE+GAUGE

I chamber my barrels in 223 Wylde IIRC. I use standard 223 GO and NOGO gauges for this work. I agree with M4Madness that if you can afford only one gauge use the Field gauge.

But, I really recommend that you use 2 gauges when cutting chambers and setting headspace.

Since you are just making sure that you dont have excessive HS strip the bolt of the extractor and ejector, insert the NOGO or FIELD gauge and using finger pressure only try to close the bolt/bolt carrier. If the bolt carrier group goes into battery you have excessive HS.

This means the cartridge will slam or thrust back in the chamber and pound the extractor pin among other things. This is not a safe condition.

Take care. Charles.  

Thanks for all the suggestions guys.

Charles, I agree and have ordered go and no-go gauges for 5.56 NATO. I'll let you know what I find out.

Dano, Thanks for checking out the pix. I'll replace the entire extractor assembly with the new bushmaster parts from my field parts kit. The one I have in there right now is a new one, but it's from Model 1 Sales. It looks like it is wearing a little too much at the front (top of shoulder)...might be contacting the bolt.

Here's a link to a pic of the new bolt.
New Extractor 100 rounds

It's probably OK but I'd trust the bushmaster parts to be mil spec...the Model 1 Sales parts may not be...oh well, live and learn.

I'll let you know how I make out.

Thanks to everyone for the help thus far.

Jon

HELP, I AM TOTALLY CONFUSED!!!

It seems the farther I go with this the worse it gets.

Ok original issue - breaking extractor pins. After getting all the good info here, I decided to take the gun to a local shop that specializes in AR's. Good solid shop and staff - I definitely trust them.

I explained the problem to them. They took one look at the bolt and showed me the problem. The hole for the extractor pin was elongated on one side! The extractor itself had OVAL holes.

So he sold me a new bolt for $40.00 and I was on my way.

Now keep in mind that I've already bought a new carrier too.

So I went home and put everything back together.

I got the headspace gauges - Clymer 5.56 NATO GO and NO GO.

So here are the results of my not-so-scientific headspace check.
I only used finger pressure for my test, except as noted.

I used the headspace gauges and an unfired Lake City XM193 round for "real world" data.

ORIGINAL CARRIER & BOLT = Closes on both GO and NO GO Gauges and the XM193 round of course.

NEW CARRIER & BOLT = Does NOT close on GO and NO GO Gauges. Closes on XM193. If I slap it in a little harder (As if the buffer spring were pushing it), it will close on the GO Gauge. When it doesn't close, it appears that the locking lugs can't get in far enough to turn.        

ORIGINAL CARRIER & NEW BOLT =  Same as above...Does NOT close on GO and NO GO Gauges. Closes on XM193. If I slap it in a little harder (As if the buffer spring were pushing it), it will close on the GO Gauge.

NEW CARRIER & ORIGINAL BOLT = Closes on both GO and NO GO Gauges and the XM193.

So what the hell does all this mean????

Do I have a bad\out of spec NEW bolt? I don't think so...it's brand new Stag Arms part...but you never know...

Do I have a bad\out of spec NEW carrier? It a cheap Model 1 Sales part so it might be suspect...but it does gauge properly with the Original bolt.

Could the head spacing be wrong on the barrel extension?

And lastly...Should I stop being so anal? Just stop measuring all this sh!t and go shooting???

Please help!!!!

Jon

Jnorthway --

Your missing one gauge....where is the "field gauge"  

Ideally you want the bolt headspace to be somewhere between the Go and the No-go gauge..........which means with slight finger pressure your bolt will close on the go gauge but NOT on the no-go gauge.

Older systems with more wear will show the headspace to be between the No-go gauge and the FIELD gauge.    This means your bolt will close on the Go gauge & No-go gauge but NOT on the Field gauge. NO rifle should be fired if it closes on the "field" gauge! IMHO.

So without the above mentioned field gauge.........you have an incomplete test of your headspace SINCE it closed on the No-go gauge.

Dano can jump in here,,,,,,,but I would test this critical measurement if I was swapping out carriers and bolts like you are doing. At least make sure the rilfe doesn't close on the field gauge.

JF.

Dano and Sniper,

I have purchased a 5.56 NATO Field Gauge as well. I figure that It'll be good to have all three anyway. Brownells does sell all three gauges in 5.56 NATO (Clymer gauges).

Dano...message received, I'll stop getting myself all wound up with the headspace issue and go shoot the gun. I'll let you know how i make out with the extractor pin breakage issue. I'm pretty sure it's going to be fine now with the new bolt.

Thanks for everyone's help. You guys (and this site) rock.

I'll keep you posted,

Jon

Im not pretending to know everything about the AR. But that extractor shouldn't be rubbing and wering like it is.  Like your gunsmith found the holes wallord out .That prabol;y was your problem. It's asways great to check HS . Don't let this discourge you with AR's . This isn't the norm. I have had to send an AK back to the factory 3 times because it wouldn't function either. The Best you can do for yourself is buy known quality parts. Seemingly you did that mostly except for the model one sales.  I will always buy Bushie and RRA and Colt before most anybody else. And there praboly made by the same subcontractor anyhow. But those companys have a reason to put out quality rifles and parts. SALES...... Good luck WarDawg.

To all who assisted me with my issue here, thank you very much for the benefit of your experience.

Shot abot 300 rounds between yesterday and today with no issues...Extractor spring still in 1 piece!

Gun shot great...I did have 1 FTE yesterday but that was it. I was using some weird old Remington stuff so that may have been the cause.

It ran like a champ today...200+ rounds of various ammo Federal AE, Lake City XM193 and some  Wolf too.

So basically I replaced the entire bolt assembly and the gun runs great now.

I did buy a Field gauge so I'll be checking the headspace with original bolt when that comes in.

I checked the new bolt with the GO gauge after shooting...still pretty tight but getting better. I don't think I have any worries there.

Now an opinion question...Should I contact the seller of this gun and get a little money back or what?

The parts that I HAD to replace cost me about $60.00. I also replaced a few other parts that I now realize had nothing to do with the actual issue.

In the process I have learned a tremendous about the gun, which is invaluable, but I did have to learn it the hard, kind of frustrating way.

I know I bought a used gun, but I did assume, (and ask) and was told that it would run OK.

I must say that the seller has been real good about helping me with info\experience regarding some other minor FTF and FTE issues. And as stated above, he has also offered to reimburse me for any parts...just send him the receipts. I really don't think that he realized the bolt assembly was bad when he sold me the gun.

What do you guys think??

Am I being too nice?

If the original bolt closes on the FIELD gauge, I will definitely ask for reimbursement for my parts.

Jon

I bought the Brownell's Colt 5.56 Field Gauge (1.4376") since I only have 5.56 NATO chambers. The bolt carrier does not sit flush with the upper receiver when "chambering" this guage using a stripped bolt and finger pressure (No close on field gauge = SAFE condition, IIRC).

Well, I got the FIELD Gauge tonight and sure enough the damn bolt closed on the original Carrier\Bolt combination. These are the original parts. This does not make me happy.

I have in fact verified with the manufacturer that the barrel has a 5.56 NATO chamber, so my gauges are the correct ones. I have a full set of Clymer 5.56 NATO.

My basic understanding of headspace is that if a bolt closes on the FIELD Gauge, then it is UNSAFE and should not be fired. Am I correct?

Dano, I know you said that carrier has no affect on headspace, and of course you were correct. The new carrier\old bolt combo produced exactly the same results.

So I guess it's time to see if the seller is going to make good on his offer to reimburse me for my parts...

Jon

Closing on the FIELD gauge is definitely an UNSAFE condition. If you were guaranteed that the gun would function, be operational and safe to shoot you now need to pursue a warranty claim against the seller. Charles the Gunsmith.  

All is good. Contacted seller via email tonight.

Holy fast return call Batman...Within 5 minutes of sending it my phone rang.

Bottom line is that seller is going to reimburse me for the new bolt assembly.

I knew he would. I think he was more upset about it than me!

So my gun runs awesome, the person who sold it to me is a stand up guy, and I learned a sh!tload about AR's in the process from all you good people.

Life is good!!

Thanks for all your help,

Jon

Hello all, thanks for helping Jnorthway  getting this thing running. I havent heard from J in a while and as far as i knew it was running. I did advertise and sell it with the promise that it ran. When he told me it didnt run i came up with suggestions and offered help in any way i could, even $. J is WAY to easy going and i wish he would of let me know there was still a problem i would of sent $ sooner. I dont go threw this troubleshooting site or i would of chimed in earlier (he just emailed me and i called him and he told me about it). The gun ran great for us, never had a problem but it was the wifes gun and she shot .22's out of it 90% of the time and when i sold it i took one of my bolts for my M16 and put it in the gun for J. It was a used bolt but wasnt anything wrong with it to my knowledge, now i know there was and am sending him $ tommorow to replace it. Leads me to beleive maybe my M16 is having issues that i need to check into, it runs 100% as anyone here in MO that attends my MG shoots will tell ya but im gonna check into it. Any how thanks to you all, and Jnorthway, Im sorry again for the whole ordeal, i wish i would of known about this earlier as you have had the gun for a month now and i would of made it better sooner if had i known.
BeltfedMG

Quoted: Closing on the FIELD gauge is definitely an UNSAFE condition. If you were guaranteed that the gun would function, be operational and safe to shoot you now need to pursue a warranty claim against the seller. Charles the Gunsmith.

+1

The operator should make sure to use a stripped bolt (no extractor or ejector) and using hand pressure, gently push the bolt carrier towards the chamber. If it closed (the bolt carrier was flush with the rear of the upper receiver) then that's an unsafe condition. I wonder how many thousands of rounds have passed through that barrel if it closed on a field gauge

Quoted: Hello all, thanks for helping Jnorthway  getting this thing running. I havent heard from J in a while and as far as i knew it was running. I did advertise and sell it with the promise that it ran. When he told me it didnt run i came up with suggestions and offered help in any way i could, even $. J is WAY to easy going and i wish he would of let me know there was still a problem i would of sent $ sooner. I dont go threw this troubleshooting site or i would of chimed in earlier (he just emailed me and i called him and he told me about it). The gun ran great for us, never had a problem but it was the wifes gun and she shot .22's out of it 90% of the time and when i sold it i took one of my bolts for my M16 and put it in the gun for J. It was a used bolt but wasnt anything wrong with it to my knowledge, now i know there was and am sending him $ tommorow to replace it. Leads me to beleive maybe my M16 is having issues that i need to check into, it runs 100% as anyone here in MO that attends my MG shoots will tell ya but im gonna check into it. Any how thanks to you all, and Jnorthway, Im sorry again for the whole ordeal, i wish i would of known about this earlier as you have had the gun for a month now and i would of made it better sooner if had i known. BeltfedMG

It sounds like it worked out for everyone

Sean