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BigCumfy
06-24-2012, 4:41 PM
I am very new to firearms and just finished building/assembling my 1st AR 15. I brought it to the range today to shoot it. Checked everything. Loaded it, chambered a round, turned safety off, pulled trigger, and dirt flies behind target. Then I check to see if my gas tube and BCG chambered the next round. It looked good, then I fired. Tried to fire the 3rd round and noticed my bolt jammed onto a bullet. I released the mag and cleared it out. Then tried again. Again, the bullet didn't go into the chamber and the bolt was pressing on it. As I clear the bullet out again, some metal fragments came out. I realize its the teeth on the bolt. My friend built the exact same rifle and his is fine. Only thing different was the BCG. However both NiB, just different companies. Any ideas why this would happen? Bad BCG? Too much/not enough headspace? I'm sure its my fault, however, any help would be appreciated. Again, I am very new to firearms and AR15's. This is my 1st rifle/ar15. Thanks in advance for your time and suggestions!

technique
06-24-2012, 4:49 PM
That's (although I've done it twice) not normal.
Return it to your manufacturer.

Share with us a few more details, what ammo, what companies make the parts your gun consists of, who assembled it...etc

Kappy
06-24-2012, 4:52 PM
Aside from the defect, a nice BCG. I would recommend contacting the company and seeing what they can do for you.

BigCumfy
06-24-2012, 4:55 PM
That's (although I've done it twice) not normal.
Return it to your manufacturer.

Share with us a few more details, what ammo, what companies make the parts your gun consists of, who assembled it...etc

Thanks for your prompt reply! I was using New Federal Americal Eagle .223 ammo purchased from Walmart. AR details below.

Spikes Upper/Lower
Spikes FN CHF 16" Barrel
RRA LPK
WMD NiB BCG

loosewreck
06-24-2012, 4:55 PM
That's (although I've done it twice) not normal.


Tech, given that it's a decent bolt, what what would cause this kind of damage? This is the first time I've seen anything that extreme.

BigCumfy's pic:
http://i274.photobucket.com/albums/jj265/Recluse76/attachment-2.jpg

BigCumfy
06-24-2012, 5:03 PM
Another thing, should I be worried about my Upper and/or lower and any internal parts being damaged as well?

BigCumfy
06-24-2012, 5:17 PM
Tech, given that it's a decent bolt, what what would cause this kind of damage? This is the first time I've seen anything that extreme.

BigCumfy's pic:
http://i274.photobucket.com/albums/jj265/Recluse76/attachment-2.jpg

Yes, that damage in 2 rds fired seems EXTREME.

calishine
06-24-2012, 5:44 PM
Big,

What part of the rifle did you assemble?

G38xOC
06-24-2012, 5:47 PM
whoaaaaaa

LovingTheYear1911
06-24-2012, 5:54 PM
Is the BCG aligned correctly with the chamber? Looks like it may of been off and the teeth slammed in the chamber causing them to break. Is the chamber damaged at all?

818gtiguy
06-24-2012, 6:13 PM
This is why you should buy HP and MPI bolts....High pressure tested and magnetic particle inspected. That bolt for sure missed that process.

BigCumfy
06-24-2012, 6:17 PM
Big,

What part of the rifle did you assemble?

I assembled the whole thing.

BigCumfy
06-24-2012, 6:23 PM
Chamber and feed ramps seem fine. If the gas tube was slightly off would it cause the BCG to not properly align?
155925155926155927

Munny$hot
06-24-2012, 6:24 PM
Do not fire your rifle again until you have it head spaced. If you assembled the barrel to upper receiver than yes it is your fault but if bought a complete upper and put together than cmmg is to blame unlesss your bolt/carrier is defective or out of spec WMD is to blame. I would contact both companies ASAP. CMMG has excellent customer service and im shure they will handle it as if you where their only customer.

BigCumfy
06-24-2012, 6:33 PM
Do not fire your rifle again until you have it head spaced. If you assembled the barrel to upper receiver than yes it is your fault but if bought a complete upper and put together than cmmg is to blame unlesss your bolt/carrier is defective or out of spec WMD is to blame. I would contact both companies ASAP. CMMG has excellent customer service and im shure they will handle it as if you where their only customer.

Yup I guess it was my fault. I did assemble it all. I don't think I can check headspace with a broken bolt. WMD has been contacted and if I'm lucky and they send me a new one, I will check headspace. Thanks!

calishine
06-24-2012, 6:50 PM
Yeah, if I had to take a guess it would be one of three things:

Headspacing: You're actually lucky the rifle didn't blow out the mag and a piece of the receiver and you're ok. It's why I recommend others to headspace before shooting.

Faulty BCG: There is a reason the top tier mfr. do hpi/mp testing.

Ammo: Bad round blew out the rifle.

A fourth less likely cause can actually be that coating. It could have caused a change the critical tolerances.

My guess of the four would be the headspacing. However, I'm sure the mfr. will be able to tell you for sure.

6mmintl
06-24-2012, 7:08 PM
Improper bolt heat treatment

Munny$hot
06-24-2012, 7:16 PM
The gas tube will not affect the bolt from lining up, but it may not allow it to close fully. You can look at the end of your tube for rub marks

818gtiguy
06-24-2012, 8:21 PM
Improper bolt heat treatment

This

rero360
06-24-2012, 8:37 PM
Do not fire your rifle again until you have it head spaced. If you assembled the barrel to upper receiver than yes it is your fault

I disagree with this, on most other rifles it would be true, however on an AR the headspace is set by the receiver extension being attached to the barrel, something most people (I don't know of anyone who does) do not do themselves, 99.999% of barrels come with the extension already attached and secured. mounting the barrel in the upper receiver has no effect on headspacing at all. So if it was headspacing, the barrel maker would be the responsible party, not the OP.

Not given the photographic evidence, and the details, I'm going to go with it being a bad bolt, machined wrong creating failure points from stress risers or, and more likely, a flaw in the coating application and or just a bad hunk of raw stock right from the get go.

I doubt it was the ammo as AE tends to be on the weak side (compared to 5.56) so unless you got a bad round, it happens infrequently, my money is a bad bolt. Also if it was bad ammo the damage the rest of the rifle would have been a lot more severe.

CIV Tactical
06-24-2012, 8:41 PM
did u put the barrel extension on or did the barrel come with it. If it came factory it was most likely headspaced when they put the extension on and put the index pin in it. You can still check the headspace even though the lugs are broken off. Just remove the ejector and or extractor and use the proper gauges. Were the broken peices in the extension or in the upper receiver. If they broke in the extension it could be overgassing and blowing the bcg back to fast to completely unlock. Anyways hope this helps

BigCumfy
06-24-2012, 9:06 PM
did u put the barrel extension on or did the barrel come with it. If it came factory it was most likely headspaced when they put the extension on and put the index pin in it. You can still check the headspace even though the lugs are broken off. Just remove the ejector and or extractor and use the proper gauges. Were the broken peices in the extension or in the upper receiver. If they broke in the extension it could be overgassing and blowing the bcg back to fast to completely unlock. Anyways hope this helps

I ordered it with barrel extension on and new from the factory. There were some pieces in the extension and most fell out of the upper. I'll check the headspace. Thanks!

BigCumfy
06-24-2012, 9:13 PM
I disagree with this, on most other rifles it would be true, however on an AR the headspace is set by the receiver extension being attached to the barrel, something most people (I don't know of anyone who does) do not do themselves, 99.999% of barrels come with the extension already attached and secured. mounting the barrel in the upper receiver has no effect on headspacing at all. So if it was headspacing, the barrel maker would be the responsible party, not the OP.

Not given the photographic evidence, and the details, I'm going to go with it being a bad bolt, machined wrong creating failure points from stress risers or, and more likely, a flaw in the coating application and or just a bad hunk of raw stock right from the get go.

I doubt it was the ammo as AE tends to be on the weak side (compared to 5.56) so unless you got a bad round, it happens infrequently, my money is a bad bolt. Also if it was bad ammo the damage the rest of the rifle would have been a lot more severe.

Thanks, I've already sent an email to the BCG company and will follow up with a phone call tomorrow. I'll still check headspace. I've read and talked to so many people that never checked headspace on their builds and had no issues. Everything I ordered was "MilSpec" and new. My friend ordered the same upper and barrel, however different BCG's and his was fine and has fired well over 500 rds already. Oh well, this is a learning experience and I appreciate everyone's advice and suggestions.

CIV Tactical
06-24-2012, 9:50 PM
its hard to see in the picture but are there any marks on the extension lugs where it looks like the bolt lugs hit or caught. it looks like your extension is aligned and clocked right with the upper receiver feedramps. Im just curious now cause Ive never seen that kind of damage and I want to know. Anyways keep us posted

gunnerstuff
06-24-2012, 9:51 PM
Improper bolt heat treatment

That has my vote also. From the failure, you can see that it failed at an approximate 45* angle. That is indicative of ductile metal failure (soft). Once metal is heat treated, and becomes stronger but more brittle, it will fail almost straight across.

Here is a simple test. Take a file to one of the broken off pieces. If it is easy to file, it is not heat treated, as the bolts metal is in the machinable state. After heat treating the bolt and file are of almost equal hardness. As a matter of fact some of the 'cheap' (harbor freight type) files gall themselves and not the base metal.

Either way, it needs to go back to the MFG.

BigCumfy
06-24-2012, 9:55 PM
its hard to see in the picture but are there any marks on the extension lugs where it looks like the bolt lugs hit or caught. it looks like your extension is aligned and clocked right with the upper receiver feedramps. Im just curious now cause Ive never seen that kind of damage and I want to know. Anyways keep us posted

Will do!

technique
06-24-2012, 9:55 PM
BigCumfy,

While no one can give you an answer with 100% certainty, especially without seeing the weapon, I can tell you from experience that I'm connecting the dots. Your situation is similar to mine, and many I have seen first hand before.

Federal ammunition- XM193/American Eagle/Tactical Black box

While this could just be that it is a popular source of ammunition, EVERY malfunction/breakage I've had and have seen, and this includes catastrophic events- the previously mentioned ammo was being used. Save that batch of ammo just in case you need it for warranty reasons. When I broke both my bolts I was using Fed 55gr. ammo, every time I've run a gun hard with this ammo I've had blown primers and stuck cases, this is especially true in hotter months.

MPI/HP testing

Find out if the maker of your bolt (who probly didn't ACTUALLY make the bolt) did any testing and if it was individually or batch tested. At the time, Stag and RRA were batch testing, I broke bolts worse than yours, completely shattered, from both those companies.


Lastly- **** happens. Live and learn, and be grateful you weren't hurt.
Keep us up to date.

kendog4570
06-24-2012, 10:00 PM
=Kappy;8811921]Aside from the defect, a nice BCG. ...


????

What the...?
Whats nice about it? It failed. It shattered like glass. Way too hard on the "C" scale. Crap product from a boutique mfg./supplier.
I hate to use the phrase, but get something "milspec", and spend your bling money on ammo and practice.
Uncle Sam experimented with hard chromed bolts and carrriers about 50 years ago, and decided it was not the ticket. What has changed?

6mmintl nailed it. Improper bolt heat treatment.

BigCumfy
06-24-2012, 10:16 PM
That has my vote also. From the failure, you can see that it failed at an approximate 45* angle. That is indicative of ductile metal failure (soft). Once metal is heat treated, and becomes stronger but more brittle, it will fail almost straight across.

Here is a simple test. Take a file to one of the broken off pieces. If it is easy to file, it is not heat treated, as the bolts metal is in the machinable state. After heat treating the bolt and file are of almost equal hardness. As a matter of fact some of the 'cheap' (harbor freight type) files gall themselves and not the base metal.

Either way, it needs to go back to the MFG.

I just used a harbor freight finishing file on a piece and although it was like cutting through butter, I was able to file it down. Thanks!

kendog4570
06-24-2012, 10:22 PM
I just used a harbor freight finishing file on a piece and although it was like cutting through butter, I was able to file it down. Thanks!

A properly heat treated bolt will cut easily with sharp high speed steel tooling. A file may not be the best way to tell what state it is in.

BigCumfy
06-24-2012, 10:26 PM
BigCumfy,

While no one can give you an answer with 100% certainty, especially without seeing the weapon, I can tell you from experience that I'm connecting the dots. Your situation is similar to mine, and many I have seen first hand before.

Federal ammunition- XM193/American Eagle/Tactical Black box

While this could just be that it is a popular source of ammunition, EVERY malfunction/breakage I've had and have seen, and this includes catastrophic events- the previously mentioned ammo was being used. Save that batch of ammo just in case you need it for warranty reasons. When I broke both my bolts I was using Fed 55gr. ammo, every time I've run a gun hard with this ammo I've had blown primers and stuck cases, this is especially true in hotter months.

MPI/HP testing

Find out if the maker of your bolt (who probly didn't ACTUALLY make the bolt) did any testing and if it was individually or batch tested. At the time, Stag and RRA were batch testing, I broke bolts worse than yours, completely shattered, from both those companies.


Lastly- **** happens. Live and learn, and be grateful you weren't hurt.
Keep us up to date.

Thanks Technique. I am grateful that I did not get hurt and for all of the advice on this thread!

technique
06-24-2012, 10:28 PM
Ya know, it's a common practice especially with places that NiB or Chrome, to cyro treat parts. Not heat treat.

BigCumfy
06-24-2012, 10:31 PM
[QUOTE=Kappy;8811921]Aside from the defect, a nice BCG. ...QUOTE]


????

What the...?
Whats nice about it? It failed. It shattered like glass. Way too hard on the "C" scale. Crap product from a boutique mfg./supplier.
I hate to use the phrase, but get something "milspec", and spend your bling money on ammo and practice.
Uncle Sam experimented with hard chromed bolts and carrriers about 50 years ago, and decided it was not the ticket. What has changed?

6mmintl nailed it. Improper bolt heat treatment.

Thanks, I'll order a basic non-NiB or non-Chrome BCG for it. Its worked for years for our military, I'm sure it will be just fine defending from those paper targets. If I happen to get a replacement, then I guess I'll have a backup for the range bag.

kendog4570
06-24-2012, 10:39 PM
[QUOTE=kendog4570;8813432]

Thanks, I'll order a basic non-NiB or non-Chrome BCG for it. Its worked for years for our military, I'm sure it will be just fine defending from those paper targets. If I happen to get a replacement, then I guess I'll have a backup for the range bag.


The Double Star one from Brownells is decent for the money and they claim it is MP tested. I have used a few in builds and have heard no negative feedback. Bushmaster is a little more money but have always been good. Not sure where they are now that Remington has bought them out, but I would bet it is still good stuff.

BigCumfy
06-24-2012, 10:52 PM
[QUOTE=BigCumfy;8813580]


The Double Star one from Brownells is decent for the money and they claim it is MP tested. I have used a few in builds and have heard no negative feedback. Bushmaster is a little more money but have always been good. Not sure where they are now that Remington has bought them out, but I would bet it is still good stuff.

Thanks Kendog!

Bladewurk
06-24-2012, 11:16 PM
Hello, just a WAG..Hydrogen embrittlement from Hard Chrome process??:cool:
Hydrogen Embrittlement: Hydrogen embrittlement can occur when hardened tool steel (Rc 52 or harder) is plated with industrial hard chrome. Stresses caused by the formation of hydrogen in the deposit can render the component susceptible to fracture. Although overlooked by many platers, this problem is easily solved by baking the component at 350 F within 8 hours of plating


http://en.wikipedia.org/wiki/Hydrogen_embrittlement

Toten Kopf
06-24-2012, 11:20 PM
I disagree with this, on most other rifles it would be true, however on an AR the headspace is set by the receiver extension being attached to the barrel, something most people (I don't know of anyone who does) do not do themselves, 99.999% of barrels come with the extension already attached and secured. mounting the barrel in the upper receiver has no effect on headspacing at all. So if it was headspacing, the barrel maker would be the responsible party, not the OP.

Not given the photographic evidence, and the details, I'm going to go with it being a bad bolt, machined wrong creating failure points from stress risers or, and more likely, a flaw in the coating application and or just a bad hunk of raw stock right from the get go.

I doubt it was the ammo as AE tends to be on the weak side (compared to 5.56) so unless you got a bad round, it happens infrequently, my money is a bad bolt. Also if it was bad ammo the damage the rest of the rifle would have been a lot more severe.

LISTEN TO WHAT THIS POSTER STATES...He knows what he's talking about!!

Dhena81
06-24-2012, 11:53 PM
Glad your ok OP this is one of the reasons I wear ballistic eye pro Oakley, Wiley X, Numa tactical, ect.

SocomM4
06-25-2012, 1:49 AM
Bad bolt.

Get a Fail Zero.

NSR500
06-25-2012, 3:23 AM
I've never cracked a bolt, but I have chipped one. The reason it chipped was poor machining. The bolt tail section was not 100% round and would bind at full lock. My gunsmith friend thinks that due to this the bolt was slightly rotated as it slammed into the barrel extension.
Get a new bolt, check headspace, and shoot it.

BigCumfy
06-25-2012, 4:14 AM
Glad your ok OP this is one of the reasons I wear ballistic eye pro Oakley, Wiley X, Numa tactical, ect.

Thanks!

BigCumfy
06-25-2012, 4:15 AM
I've never cracked a bolt, but I have chipped one. The reason it chipped was poor machining. The bolt tail section was not 100% round and would bind at full lock. My gunsmith friend thinks that due to this the bolt was slightly rotated as it slammed into the barrel extension.
Get a new bolt, check headspace, and shoot it.

That's the plan...

BigCumfy
06-25-2012, 6:35 AM
WMD Guns already responded and are sending a new BCG out to me with a return label for the defective one for inspection. Also offered 50% off any coating services they do. Pretty good customer service IMO.

m03
06-25-2012, 7:39 AM
Uncle Sam experimented with hard chromed bolts and carrriers about 50 years ago, and decided it was not the ticket. What has changed?


I doubt that presence of hard chrome had anything to do with the bolt lugs shearing off. If you're implying that it is an indicator of a low quality bolt, tell that to Young Manufacturing.

kendog4570
06-25-2012, 7:51 AM
I doubt that presence of hard chrome had anything to do with the bolt lugs shearing off. If you're implying that it is an indicator of a low quality bolt, tell that to Young Manufacturing.

See a few posts above re: Hydrogen Embrittlement. Have also seen this type of failure in the construction industry. Some structural bolts (A325 and A490) are hot dip galvanized, and if done wrong are noticably more brittle and prone to breakage. They break MUCH more easily when impacting them to torqe specs, compared to non plated bolts. If done correctly on a rifle bolt, I imagine there is some benefit, but probably not worth the added cost.

My oldest son uses the M4 every day for the last 4 years at "work", and they do not have any trick coatings.

TreeHugger
06-25-2012, 8:03 AM
I ordered it with barrel extension on and new from the factory. There were some pieces in the extension and most fell out of the upper. I'll check the headspace. Thanks!

Young manufacturing stated thst checking headspace for the bolt is almost uneccessary in an ar, since it is milspec, and that you would have a better chance at winning the lottery than the rifle blowing up on you. Some other top tier manufacturers also stated the same. My guess is that the bolt wss defective to begin with.

m03
06-25-2012, 8:08 AM
See a few posts above re: Hydrogen Embrittlement. Have also seen this type of failure in the construction industry. Some structural bolts (A325 and A490) are hot dip galvanized, and if done wrong are noticably more brittle and prone to breakage. They break MUCH more easily when impacting them to torqe specs, compared to non plated bolts.

I'll concede the point in the instance of poorly manufactured bolts, which this one apparently was. It has everything to do with proper manufacturing and quality control, though.

My oldest son uses the M4 every day for the last 4 years at "work", and they do not have any trick coatings.

Cool story, assuming you don't consider parkerizing/phosphate a trick coating. There are plenty of examples of other military firearms with non-parked/non-phosphated bolts where you don't see the lugs shearing off (SCAR, AK47, etc). I don't seem to recall lugs breaking as being a major complaint of the early M16s either.

kendog4570
06-25-2012, 8:18 AM
Kind of funny, when he was going thrugh Basic, they cleaned them so much that the phosphate was gone and you could eat off it, and now with his unit, they dont clean them to death, and leave a little carbon left in there for reliability.
Some folks he works with are using the scar and they like it, but the difference in the two guns is not significant enough to warrant the logistical nightmare of switching over.

m03
06-25-2012, 8:34 AM
Some folks he works with are using the scar and they like it, but the difference in the two guns is not significant enough to warrant the logistical nightmare of switching over.

Not to get too far off-topic, but isn't it funny? They want something similar to what they already have, but as soon as those criteria are met, then it's too similar and therefore the change can't be justified.

They're waiting for something revolutionary, but arms development is all about evolution, not revolution.

ott1
06-25-2012, 10:28 AM
The bolt is NiB coated and not hard chrome so it's not affected by Hydrogen embrittlement.

SocomM4
06-25-2012, 10:44 AM
I'm loling at the people who are blaming a coating.
The reasons the Military doesn't use chromed or NiB BCGs are very simple,
1 cost,
2 they're shiny.


Military hates both.




It's just a bad bolt. End of speculation.

send it_hit
06-25-2012, 4:55 PM
holy crap. :eek:

BigCumfy
06-28-2012, 8:47 PM
Got my headspace gauge today as well as the replacement BCG and another one I purchased. The replacement looks exactly the same as the broken one, but just with the lugs attached. Checked headspace on the broken one and the BCG closed fully and was flush on the back of the upper. I then checked the replacement and the BCM BCG and both would not completely go into battery and was sticking out slightly out of the back of the upper. Is there any reason I shouldn't test the new BCG's out? If not, since I know headspace is good on both new BCG's, I will go to the range within the week and report back.

ott1
06-28-2012, 11:09 PM
Take all of your parts to a qualified gunsmith to check headspace before you go to the range.

http://www.ar15.com/mobile/topic.html?b=3&f=4&t=315921

Dirtbiker
06-29-2012, 9:53 AM
Got my headspace gauge today as well as the replacement BCG and another one I purchased. The replacement looks exactly the same as the broken one, but just with the lugs attached. Checked headspace on the broken one and the BCG closed fully and was flush on the back of the upper. I then checked the replacement and the BCM BCG and both would not completely go into battery and was sticking out slightly out of the back of the upper. Is there any reason I shouldn't test the new BCG's out? If not, since I know headspace is good on both new BCG's, I will go to the range within the week and report back.

What kind of gauge are you using? A GO, NO GO, or a FIELD?

Cobrafreak
06-29-2012, 10:43 AM
The steel in your bolt was too hard (brittle) caused by improper heat treating. If you remove whats left of the bolt and put it on an anvil and whack it with a hammer it will break like glass. If this was a bolt action rifle it would have gone through your head and killed you. Get a MPI bolt and it won't happen like this. If you build your own rifle it's a good idea to have a GO and NO GO gauge. Brownells sells them and it will let you know without firing a round that your head space is within safe specs.

BigCumfy
06-29-2012, 10:48 AM
Field Gauge.

kendog4570
06-29-2012, 11:28 AM
Take all of your parts to a qualified gunsmith to check headspace before you go to the range...


That's some good advice.

BigCumfy
06-29-2012, 12:32 PM
That's some good advice.

Agreed!

mdib870
06-29-2012, 3:35 PM
your bolt proly rotated by the force of recoil your bolt teeth to slam into your locking lugs which proly caused your bolt to fail thats my guess

SURVIVOR619
06-29-2012, 4:00 PM
I disagree with this, on most other rifles it would be true, however on an AR the headspace is set by the receiver extension being attached to the barrel, something most people (I don't know of anyone who does) do not do themselves, 99.999% of barrels come with the extension already attached and secured. mounting the barrel in the upper receiver has no effect on headspacing at all. So if it was headspacing, the barrel maker would be the responsible party, not the OP.

Not given the photographic evidence, and the details, I'm going to go with it being a bad bolt, machined wrong creating failure points from stress risers or, and more likely, a flaw in the coating application and or just a bad hunk of raw stock right from the get go.

I doubt it was the ammo as AE tends to be on the weak side (compared to 5.56) so unless you got a bad round, it happens infrequently, my money is a bad bolt. Also if it was bad ammo the damage the rest of the rifle would have been a lot more severe.

LISTEN TO WHAT THIS POSTER STATES...He knows what he's talking about!!

I recently received a lesson in this from vytamenc22 after purchasing a barrel from him. All the talk on the forum about headspacing this and headspacing that, yet I had not seen this particular portion of the headspace issue... Wish more people would raise this simple, yet important point...

Pthfndr
06-29-2012, 7:04 PM
That's some good advice.

Says the Gunsmith :)

But I agree. If you aren't absolutely sure what you are doing or checking, take it to a Gunsmith (Kendog is a good one), and watch how it's done.

arsilva32
06-29-2012, 7:25 PM
um you said it did not go all the way to full locked battery, what gage where you using go , no go , field? it matters

ott1
06-29-2012, 8:43 PM
Post #57 states he used a field gage.

BigCumfy
07-15-2012, 7:29 PM
FYI, I brought it to Mike at Gecko Guns in Pinole and he gave it his approval that it is safe to shoot. I did use the Bravo Company BCG instead of the replacement one and it worked flawlessly. Shot 400 rds last Friday at Chabot Gun Club with NO ISSUES!!! Thanks for everyone's comments and advice. I appreciate it!!! Now to the next project... Upgrade trigger on the AR, change my factory sights on my XDm and STOP SB 249!!! 159382159383

Mail Clerk
07-15-2012, 7:54 PM
Regardless of what happened the bolt can be replaced with a new one in NIB. Just look in the Brownells catalog and go from there.

Mail Clerk

Calif Mini
07-15-2012, 8:25 PM
First - Just glad no one was hurt which was only a trigger pull away.

I have seen fractures similar to this when proper heat treating had been performed but in the shuffle to the tempering stage, this one (or more) bolt was missed.

Thus the bolt is way to hard and will fracture glasslike. Just like the bolt did.

This bolt will not readily file when tested but as someone previously stated, the properly tempered bolt would be able to be filed a little.

Improper or missed tempering is my vote.