How long before the average AR15 bolt needs to be replace do to lug facture???
- Thread starter charliebrown1999
- Start date
More rounds than most can afford.
How long is your gas system? Who made your bolt and what material is it? What ammunition do you use? Was a proof round fired in it?
My gas rings failed the ring test at about 2,500 of Nato rounds but the bolt is ok after 6,000 rounds and counting...I check all the time for signs of failure...
I was always told that when you replace a barrel you have to replace the bolt with it because the lugs in both wear/seat together. So using that theory your barrel will be shot before the bolt breaks... Unless it's a JP bolt, ive seen 4 of them break at the cam hole.
If a bolt will last as long as a barrel, I’d be stoked. Depends on the barrel, though, ha ha! Precision stainless barrels, I can see it. If a person got 10,000 rounds out of a bolt and barrel - damn skippy, good shit mang. The current crop of higher-end chrome lined barrels (FN based, DD, Criterion, Centurion since apparently those aren’t FN blanks!?! - so whoever’s those blanks are), is where I’m going with this. I’m still holding my breath, though. Accuracy with those well spec’ed barrels is good enough I’d like to have one bolt for the life of the barrel.
Seems like LMT Enhanced bolts don’t break, but are questionable in terms of reliability and replacement parts. Very system specific, it seems...
JP’s seem to have a pretty good track record, except the post above me (details on what was going on? Overgassed, underlubed, hot loads, out of spec upper, lots of variables - could just be a bad batch of bolts...).
I saw Paul Leitner-Wise is selling an enhanced bolt and carrier. Lot of baggage there, though. His bolts were highly regarded before the SHTF falling out, though, it seemed.
Geissele’s super duper BCG sounds good, time and documented torture will prove his system out one way or the other, being new. Wish he’d sell those bolts separate...
I’m not touching a Sharp’s with a 10’ stick.
Are ARP’s bolts no longer a thing?
Regardless, I’d love a bolt to go 20,000-30,000 rounds, but the pickins are slim and there isn’t a ton of verified info out there. I know Wes at MSTN has tracked a few of his builds, I trust him 100%, not many others instill that sort honesty in my mind, in my opinion. His recipe for success isn’t an off the shelf deal, though. And I don’t know the whole recipe, either, ha ha!
Seems like LMT Enhanced bolts don’t break, but are questionable in terms of reliability and replacement parts. Very system specific, it seems...
JP’s seem to have a pretty good track record, except the post above me (details on what was going on? Overgassed, underlubed, hot loads, out of spec upper, lots of variables - could just be a bad batch of bolts...).
I saw Paul Leitner-Wise is selling an enhanced bolt and carrier. Lot of baggage there, though. His bolts were highly regarded before the SHTF falling out, though, it seemed.
Geissele’s super duper BCG sounds good, time and documented torture will prove his system out one way or the other, being new. Wish he’d sell those bolts separate...
I’m not touching a Sharp’s with a 10’ stick.
Are ARP’s bolts no longer a thing?
Regardless, I’d love a bolt to go 20,000-30,000 rounds, but the pickins are slim and there isn’t a ton of verified info out there. I know Wes at MSTN has tracked a few of his builds, I trust him 100%, not many others instill that sort honesty in my mind, in my opinion. His recipe for success isn’t an off the shelf deal, though. And I don’t know the whole recipe, either, ha ha!
They say replace around 4-5000 rnds.
I've never had a report of a 5.56 bolt failing but have no idea of round counts on any made in the last 12 years. I shut down the CNCs in 2017 so I don't machine any now. I've had 1 6.8 fail probably due to HOT handloads(customers words). I had 2 Grendel bolts fail, 2 in 6 months were due to an receiver that was not square. I squared the receiver for the customer and haven't heard anything since. None of the 6BRX, 270AR,270MSR 800 series or 750XD bolts have failed. None of the Titan Grendel bolts have failed. To get a number, we machined apx 350 bolts a week for 10 years.
this is the first that I heard of reliability issues with LMT bolts
Rifle length, PSA, Carpenter 158, MPI tested, Wolf Gold brass case 55gr fmj
Same here, the lobster tail dual spring extractor is a bit different but have never had an issue or need for replacement or parts.
There is a thread posted on arfcom somewhere of the guy that runs battlefield Las Vegas. He’s kept track of what has been replaced in different rifles of different makes and what has held up the best.
Much bigger than the sample size of 1 over hundreds of thousands of rounds over the same and different models of rifles.
Much bigger than the sample size of 1 over hundreds of thousands of rounds over the same and different models of rifles.
Link
www.ar15.com
High round count AR/M4's (over 100,000 rounds) and how they have handled on our range - Page 38 - AR15.COM
Firearm Discussion and Resources from AR-15, AK-47, Handguns and more! Buy, Sell, and Trade your Firearms and Gear.
www.ar15.com I’m willing to give the LMT bolt a go, if everyone here says they have no issues. Whenever they come back in stock, that is! I also don’t mind stocking up on wear parts as they become available, either.
I’d have to do some digging, but I recall people tracing bolt issues down to the enhanced bolt and replacing with a standard LMT bolt, a Colt, or BCM/DD and issues went away. I don’t think it was on this board, though, meaning it could very well be the blind leading the blind.
I’d have to do some digging, but I recall people tracing bolt issues down to the enhanced bolt and replacing with a standard LMT bolt, a Colt, or BCM/DD and issues went away. I don’t think it was on this board, though, meaning it could very well be the blind leading the blind.
Check v1 tactical for LMT products.
Also straight from the guys at V1 that have a really
Good relationship with LMT, they were talking with LMT about the EBCG/E Bolt and they said “they don’t know why anyone buys them” they are for a niche style gun and a waste on anything else. They were made for short, suppressed, full auto. If it doesn’t fit that description go with a standard bolt.
The E carrier has been great for me for dedicated suppressed builds. I’ve been running either standard LMT bolts or JP bolts without issue. I personally think it lessens the ejection port pop. I’m also tuning the gas system with BRT inserts. I think I’m up to 4 full auto e-carriers and two semi-auto carriers.
I have two Hodge barrels to build out, I’ll try the e-bolt on them and see how it goes. I’m still in the process of acquiring parts anyway.
I have two Hodge barrels to build out, I’ll try the e-bolt on them and see how it goes. I’m still in the process of acquiring parts anyway.
They were saying that it isn’t any added benefit to guns not running in those conditions.
Wonder if they would warrant their bolt to last as long as a hammer forged barrel then.
They are a non Mil-Spec barrel extension bolt, so don’t just go buy a KAC bolt when they come back in stock. Not a drop in part like the LMT is.
When one of the lugs breaks off
Is this question for real?
Do people sit around thinking this shit up? Go shoot instead.
Carrier, The carrier is what delays the unlock the bolt just rides along. The bolt is made from 9310 and has a dual spring extractor but that does not affect the timing.
Yes for real. Tom Beckstrand former Army Special Forces (Green Beret)/ Sniper instructor graduate of Ranger school and
West Point was featured on an episode of Gunsandammo TV that talked about the parts on an AR15 that might fail. Yes he also shoots alot.
I have 2 ARS that were used for 3 gun that are in the 15K+ round range with no bolt issues as of yet, One is a JP and the other is the stock bolt that came with a Factory R-15 rifle. Throat on the rem barrel is pretty bad though.
I shoot a lot too for pleasure since 23 years ago, and for a living since 2003. Short barrel, rifle length, carbines, suppressed, unsuppressed, whatever. I've only seen one lug on one bolt break on one team member's rifle down the line after an unknown thousands of rounds on his particular rifle.
This is why I recommend one have at least some access to spare parts, like bolts, gas rings, pins, springs.... and the tools to get those parts to where they need to be at home. If you're that concerned, then keep parts in your range bag. Like a spare *complete* bolt carrier group just on the odd occasion.
The old saying goes: 2 is 1. 1 is none.
JP FMOS, KAC if you have a KAC upper.
Noveske and LMT make a good milspec offering. True milspec will be made of carpenter steel, MPI, etc.
I second keeping spare parts and plenty of 'em. Also remember to keep spare parts for your proprietary stuff or stuff that uses different gas rings, etc., like the new JP bolts (which can use either or) or if you have KAC bolts which are completely different to standard AR bolts.
Also keep a complete bolt assy. in your cleaning kit. Your field cleaning kit. Not a carrier, just the complete bolt with firing pin. I wouldn't keep it in one of those Magpul grip assy.'s, just extra weight though I suppose it would be handy in certain instances. Better to keep it with the field cleaning kit in/on your gear, depending on your situation. Never know when you'll need it. A broken shell extractor is nice to have too.
I have a nice kit that came with the SR25 that has everything but I made some for the AR's and others and grab the one I need from a box to throw in the pack.
Good bolts don't often break, 6.5G and Beowulf bolts tend to break sooner than 5.56 bolts due to thinner material and more stress, so it's good to have extras of those in the drawer as well as extractors. Bolts that see a lot of wear fast tend to break sooner than ones that see wear over time.
Though good ones don't often break, if you don't have one on you then that'll be the time it does break. It always works like that.
Noveske and LMT make a good milspec offering. True milspec will be made of carpenter steel, MPI, etc.
I second keeping spare parts and plenty of 'em. Also remember to keep spare parts for your proprietary stuff or stuff that uses different gas rings, etc., like the new JP bolts (which can use either or) or if you have KAC bolts which are completely different to standard AR bolts.
Also keep a complete bolt assy. in your cleaning kit. Your field cleaning kit. Not a carrier, just the complete bolt with firing pin. I wouldn't keep it in one of those Magpul grip assy.'s, just extra weight though I suppose it would be handy in certain instances. Better to keep it with the field cleaning kit in/on your gear, depending on your situation. Never know when you'll need it. A broken shell extractor is nice to have too.
I have a nice kit that came with the SR25 that has everything but I made some for the AR's and others and grab the one I need from a box to throw in the pack.
Good bolts don't often break, 6.5G and Beowulf bolts tend to break sooner than 5.56 bolts due to thinner material and more stress, so it's good to have extras of those in the drawer as well as extractors. Bolts that see a lot of wear fast tend to break sooner than ones that see wear over time.
Though good ones don't often break, if you don't have one on you then that'll be the time it does break. It always works like that.
Anything might fail
I don't GAF what super duper soldiers have to say, bolt lugs should NEVER shear off. If you think that's a maintenance item on a rifle, then get a better rifle.
This question is nearly impossible to answer...literally could be anywhere from 1-20,000+ rounds. There are far too many variables to give any definitive answer. Stick with reputable manufacturers that are commonly known for quality/reliability and have a spare as back up.
PS Gas keys on the Bolt Carrier are also a point of failure. If you are concerned with not having an inop gun, best practice is have a complete BCG assembly as back up....better yet just buy a back up gun.
PS Gas keys on the Bolt Carrier are also a point of failure. If you are concerned with not having an inop gun, best practice is have a complete BCG assembly as back up....better yet just buy a back up gun.
Funny, back in the mid 80s I knew a guy that carried a complete spare BCG in his ruck.
Last edited:
@Constructor I got one of your barrel/bolt combos about 10 years ago, in the event either of them eventually go south do you recommend a particular replacement/spare 6.8 bolt?
The ones made by Microbest. Problem will be finding someone who will tell you that is where they get their bolts.
That is fine for shooting targets and hunting but not duty or combat. You can't hit pause while you go find another bolt of course there is always the sidearm or a pickup. I'm sure it had been back to the armorer several times. The direction of replacing after 4-5000 is so you don't get that "click" at the worst time.
I wanted a 2nd that was light and compact, this year my sidearm grew legs and yes it fits in holsters - https://www.fab-defense.com/en/category-buttstocks/id-2459/quick-deployment-folding-glock-stock.html
Last edited:
I trust your judgment as you are the real deal-saw combat with the M16 in a life and death situation. Thank you.
20” guns break bolts a lot less than short ones.
I replaced a standard LMT bolt with a LMT enhanced and had problems. The rifle is an 18” rifle length gas set up. Carbine RE with an H buffer, standard BCM carbine spring. It probably had over 1k rounds fired through it when I changed the bolt. The gun had experienced no previous stoppages. The first time after changing the bolt, the gun started having failure to feed issues. I’m assuming it was short stroking as the bolt wasn’t stripping the next round from the mag. The carrier was pushing the round up the feed ramp and it was stopping when caught between the bolt and feed ramps. I tried different mags, (Colt, Magpul, and Okay), with the same results. I put the standard bolt back and have since fired several hundred rounds with no more stoppages. I ended up using the bolt in a 16” LMT MRP and haven’t had any issues.
Last edited:
im running the e-carrier and a basic bolt matched to my barrel. A 150.00 to avoid some gas in my nose for the next 10,000+ rounds is worth it.
Sorry to burst your bubble but it is a common failure point. The lugs to the right and left of the extractor break all the time. Yes, it takes a high round count, but it happens.
FWIW - I decided to give the LWRC bolt shown below a go on a .224 Valkyrie build. Cant speak to it's longevity, but looks to have good potential.
Fits standard mill spec carriers. $129 when on sale.
From an engineering standpoint I agree with all the changes they made. It's similar to the LMT, but not a copy. From what I have found both this design & LMT's date back to 2003 ish with a lot of updating since.
BCM on left / LWRC on right. Notice extractor lugs & bolt face are fully supported on LWRC.
My take on all this, change out the bolt with the barrel, they are consumables.
I have always had spare parts for 5.56 and 308, barrels, BCG etc.
Especially since last year it was kinda hard to NOT pass up coated BCG's from Toolcraft for less than $90, BA barrels same thing $90 - $100 last year.
Anyone that takes this stuff seriously should at a minimum have 1 replacement part(s) on hand
You guys act like it's all new?
Bolts,barrels, gas rings,springs,extractors and firing pins are all consumables, PERIOD.
Does it make much sense to have a range day cut short because of a breakage from poor preventive maintenance ?
Magpul even seen fit to make a storage container in the grip.
I have always had spare parts for 5.56 and 308, barrels, BCG etc.
Especially since last year it was kinda hard to NOT pass up coated BCG's from Toolcraft for less than $90, BA barrels same thing $90 - $100 last year.
Anyone that takes this stuff seriously should at a minimum have 1 replacement part(s) on hand
You guys act like it's all new?
Bolts,barrels, gas rings,springs,extractors and firing pins are all consumables, PERIOD.
Does it make much sense to have a range day cut short because of a breakage from poor preventive maintenance ?
Magpul even seen fit to make a storage container in the grip.
I have a DPMS bcg, 20 years old with just over 13k recorded rounds fired.
Never had an issue. Only regular cleaning and lubing every 2-300 rounds.
This is my match rifle with a second barrel that shoots very well.
Never had an issue. Only regular cleaning and lubing every 2-300 rounds.
This is my match rifle with a second barrel that shoots very well.
The only bolts I have ever had fail were 6.5 Grendel bolts. Both bolts had the Lug next to the extractor fail. After the second failure, I was told that facing off the front of the upper receiver where the barrel extension mates to the upper reduces the chances of bolt breakage as it helps even out stresses on all. the bolt lugs. Since facing all upper receivers, I haven't had a bolt break.
I have never had a bolt fail in either 5.56 AR15's, or 7.62x51 AR10 type rifles. I agree with the wisdom about keeping a spare bolt around though.
I have never had a bolt fail in either 5.56 AR15's, or 7.62x51 AR10 type rifles. I agree with the wisdom about keeping a spare bolt around though.
Similar threads
