LMT Enhanced Bolt Question

[markdeerhunter]

I am currently waiting for my LMT 16in upper to arrive.I ordered it with the full auto enhanced bolt carrier group.Now i have been reading that I may be better off with the regular bolt.I was just trying to get the best I could get.Other than maybe overspending, did I make a mistake?This is my first AR so bear with me.Are there any downsides to the enhanced bolt?:confused:

[C4IGrant]

I am currently waiting for my LMT 16in upper to arrive.I ordered it with the full auto enhanced bolt carrier group.Now i have been reading that I may be better off with the regular bolt.I was just trying to get the best I could get.Other than maybe overspending, did I make a mistake?This is my first AR so bear with me.Are there any downsides to the enhanced bolt?:confused:


The enhanced bolt might work just fine, but they tend to be picky on ammo. If you only shoot mil-spec ball then you will most likely be ok.



C4

[Robb Jensen]

I'd would just go with a Colt/FN/LMT or CMT M16 carrier and a regular bolt CMT MP tested bolt. I haven't seen a LMT 'enhanced' carrier work in anything but a 14.5" full-auto w/M855. It's a solution is search of a problem.

[Heavy Metal]

I'd would just go with a Colt/FN/LMT or CMT M16 carrier and a regular bolt CMT MP tested bolt. I haven't seen a LMT 'enhanced' carrier work in anything but a 14.5" full-auto w/M855. It's a solution is search of a problem.


I run two in two different 16 inch weapons and both cycle fully using everything from Wolf to M-193 spec ammo. And I run a heavy MGI RRB buffer in both.

Perhaps they have fixed the issues in the later production.

[Dport]

I'm slow. What were these bolts supposed to "enhance?"

[Stickman]

My LMT enhanced has run very well so far on mixed ammo.

[Heavy Metal]

I'm slow. What were these bolts supposed to "enhance?"


They are supposed to be more resistant to breaking lugs due to design features in both the bolt and carrier among other things.

[markdeerhunter]

I thought the enhanced since it is chromed would be smoother cycling and easier to clean.Maybe I'm dense but what could cause a bolt upgrade to be finnicky pertaining to ammo?

[9mm MP5 Machinenpistole]

I am very much a fan of the LMT Enhanced Bolt and Bolt Carriers; especially in full-automatic fire. I have LMT Enhanced Bolt and Bolt Carriers in all four of my M4 (Class 3, full-auto) carbines. Functionality and reliability is 100-percent in both semi-automatic and full-automatic fire.

The oldest and highest round count I have on one of my LMT Enhanced Bolt and Bolt Carriers is now approximately 34,000 rounds; and, I have never experienced a stoppage or malfunction. This last weekend I went shooting and fired 2,000 rounds, mostly on full auto, without any problems.

I especially like the idea that the LMT Enhanced Bolt and Bolt Carrier were designed to solve the functionality and reliability problems in the SOCOM M4A1 carbines. If it good enough for SOCOM, it is good enough for me!

I highly recommend a LMT Enhanced Bolt and Bolt Carrier for your weapon!

[AR15barrels]

It bears mentioning here that there are two specific different "enhanced" pieces that LMT offers.
The "enhanced" bolt uses a whale-tail shaped extractor with two springs and has a relief on the lug opposing the extractor to equally load the remaining 6 lugs.
It also has the sand cuts on the lugs.
Then there is the "enhanced" carrier.
This has a re-timed cam slot to allow for a slower un-locking of the bolt, an extra exhaust port, re-located gas vent behind the bolt tail and additional metal up at the front where the carrier hits the extension in normal use.

You can get these features seperately, ie: enhanced bolt with a regular carrier or an enhanced carrier with a regular bolt, OR you can get a complete enhanced bolt carrier group.

The enhanced carrier is NOT recommended for barrels shorter than 14.5" as it extends the unlocking time and those barrels have sufficiently short dwell times that can cause problems when you extend the unlocking time.

I recommend the enhanced carriers on 14.5" and especially 16" carbines.
I don't feel that the bolt is really worth the extra money, but some people like them because they are electroless nickel plated and have that cool extractor...

[Bill Alexander]

Let us perhaps be a little more precise with regard to the details of the LMT enhanced bolt and carrier system. As shown the details are very often misinterpreted.

In the first instance one must understand why the system exists, more particulaly in the context that the design is brilliant in its execution, but as reported frequently on the errornet is not always reliable. The design basis for the assembly is specifically to enhance the durability of the M4 configuration as currently issued. This gun is to some extent unbalanced. Port pressures running military grade ammunition are well in excess of the design levels which leads to very high carrier acceleration rates (+22 f/s/s). this combined with chamber pressure drop often creates the undesirable condition that the bolt commences to unlock while still subject to a degree of head thrust from the cartridge case. The result is that the lugs are subject to a biaxial loading of both shear and bending.

The LMT system being both the carrier and the bolt seeks to operate directly in this gun and elleviate symptoms. The carrier is set up with a longer delay during the initial portion of its movement. To facilitate this longer cam path and movement of the bolt forwards in the carrier, the front edge of the carrier is extended such that it still continues to retain the extractor pivot pin. Additional exhaust vents act to drop the piston pressure faster and to relieve any blowby at the tail of the bolt.

The bolt itself is of particular interest. The function of the dual spring extractor is frequently misinterpreted as an attempt to add spring force to the extractor claw. Rather it reduces the fatigue that the extractor spring(s) undergo by allowing the use of longer springs with lower K values; the % relative compression during the movement of the extractor is reduced. Remember that additional extractor force is not required now that the carrier is slowing the extraction cycle. The mitigation of stress in the bolt is accomplished in several ways. Material is the least visible change but is important to the design. The traditional Carpenter 158 is abandoned, being replaced by a significantly tougher grade from a different manufacturer. The lugs themselves are generously radiused between lugs and at the rear the diameter is actually reduced to allow a larger transition radius to be machined. The incorrectly identified sand cuts on the lugs are stress relief cuts. These allow any individual lug to elastically deform and give a smoother load over the contact patch. While this type of feature is very difficult to calculate and even more difficult to implement it helps to place the lug in a true shear load rather than amplify the bending moment. As noted the lug opposite the extractor is relieved. This feature prevents the unequal transfer of load to the two opposite lugs but I would argue that the stress relief groove already in place largely accomplishes this purpose. This is a academic quibble so I will bow to LMT in this respect. There is one additional feature that can be found in the bolt, but I am not at liberty to disclose the detail.

When considering wether to use the LMT parts one must consider the weapon. Correctly ported guns will derive little or no benefit from a carrier that is specifically set up to absorb excessive port pressures and some degree of residual case pressure. If not sufficiently gassed the reliability will suffer. This is not a fault of the carrier rather a mistake made in the application so be careful with simple substitutions. The bolt itself is exemplary. If not constrained by a $ value the bolt is a worthy addition to any rifle and will do nothing but enhance the durability of this part of the system.

Bill Alexander

[rsilvers]

I noted the decreased tension of the extractor (in comparision to the current SOCOM 5coil copper washed extractor spring, black insert, and Oring)

When you say '5 coil' do you mean the 3.5 coil Colt spring? Or is there some 5-coil spring that is used by SOCOM? Do you have a photo of one?

http://img.photobucket.com/albums/v503/AR15forme/Extractor%20Springs/Colt1small.jpg

[trg42]

Further to Bills excellent description of the Enhanced Bolt, you can see from the picture the generous radius and stress relief cuts

http://i30.photobucket.com/albums/c347/TRG42/ar%20pics/LMTBolt.jpg

I don't use my ARs for work so I don't feel I need a super duper bolt like this. Having said that I have broken 2 DPMS bolts in my 7.62X39 AR. The only bolt that keeps chugging away in this upper is the LMT Enhanced 7.62X39 bolt

You would think the lobster tail extractor would more tension but it does not ( for the reason Bill outlined above )

It would be be wrong however to assume it has insufficient tension. See pic below of a stuck 7.62X39 case that I managed to pull out using the charging handle...and a block of wood ! The extractor had no problem holding on to this case. As you can see the build up from the laquer coating grabbed on to this case

http://i30.photobucket.com/albums/c347/TRG42/ar%20pics/wolf-6.jpg

[Xenogy]

Would the LMT enhanced bolt be good to go in a BCM 16" recce middy?

[Pappabear]

I have the Enhanced Bolts and they run great on all ammo and even when I put them in "other" carriers. From everything I have read, Bottom line, you did buy one of the finest BCG available. You did good.

[ForTehNguyen]

so if the LMT enhanced bolt was designed to counter the imbalances of the carbine gas system would it be correct to assume there is a diminished advantage using it in a midlength system?

[sdacbob]

Not for use with barrels less than 14.5" according to LMT.

http://www.lewismachine.net/product.php?p=52&cid=7&session=097eb4cb6d14d5a07b0a3dcdc25c31c5

[AR15barrels]

so if the LMT enhanced bolt was designed to counter the imbalances of the carbine gas system would it be correct to assume there is a diminished advantage using it in a midlength system?

You are confusing the carrier with the bolt.
The CARRIER is designed to counter the problems of the carbine gas system.

[LONGBOWAH]

I thought the enhanced since it is chromed would be smoother cycling and easier to clean.Maybe I'm dense but what could cause a bolt upgrade to be finnicky pertaining to ammo?

The carrier is ported differently to increase dwell time.

[LONGBOWAH]

The four big (and maybe an interrelated 5th) things you get with the LMT enhanced BCG are:

1. Carrier is ported differently to increase dwell time and thereby ease extraction (5th thing).
2. Bolt is "ion" coated.
3. Cartridge case is fully supported by bolt head.
4. Bolt heat treat is "stronger".

You most likely will not have ANY problems with your LMT bolt/carrier.

[Thomas M-4]

The four big (and maybe an interrelated 5th) things you get with the LMT enhanced BCG are:

1. Carrier is ported differently to increase dwell time and thereby ease extraction (5th thing).
2. Bolt is "ion" coated.
3. Cartridge case is fully supported by bolt head.
4. Bolt heat treat is "stronger".

You most likely will not have ANY problems with your LMT bolt.

The bolt is not ION coated I have never see that in any statement from LMT regarding the bolt?

If you read Bill Alexanders statement in this thread it explains the feature's of the bolt and carrier better than any other statement I have ever found.

[REDSKY383]

Let us perhaps be a little more precise with regard to the details of the LMT enhanced bolt and carrier system. As shown the details are very often misinterpreted.

In the first instance one must understand why the system exists, more particulaly in the context that the design is brilliant in its execution, but as reported frequently on the errornet is not always reliable. The design basis for the assembly is specifically to enhance the durability of the M4 configuration as currently issued. This gun is to some extent unbalanced. Port pressures running military grade ammunition are well in excess of the design levels which leads to very high carrier acceleration rates (+22 f/s/s). this combined with chamber pressure drop often creates the undesirable condition that the bolt commences to unlock while still subject to a degree of head thrust from the cartridge case. The result is that the lugs are subject to a biaxial loading of both shear and bending.

The LMT system being both the carrier and the bolt seeks to operate directly in this gun and elleviate symptoms. The carrier is set up with a longer delay during the initial portion of its movement. To facilitate this longer cam path and movement of the bolt forwards in the carrier, the front edge of the carrier is extended such that it still continues to retain the extractor pivot pin. Additional exhaust vents act to drop the piston pressure faster and to relieve any blowby at the tail of the bolt.

The bolt itself is of particular interest. The function of the dual spring extractor is frequently misinterpreted as an attempt to add spring force to the extractor claw. Rather it reduces the fatigue that the extractor spring(s) undergo by allowing the use of longer springs with lower K values; the % relative compression during the movement of the extractor is reduced. Remember that additional extractor force is not required now that the carrier is slowing the extraction cycle. The mitigation of stress in the bolt is accomplished in several ways. Material is the least visible change but is important to the design. The traditional Carpenter 158 is abandoned, being replaced by a significantly tougher grade from a different manufacturer. The lugs themselves are generously radiused between lugs and at the rear the diameter is actually reduced to allow a larger transition radius to be machined. The incorrectly identified sand cuts on the lugs are stress relief cuts. These allow any individual lug to elastically deform and give a smoother load over the contact patch. While this type of feature is very difficult to calculate and even more difficult to implement it helps to place the lug in a true shear load rather than amplify the bending moment. As noted the lug opposite the extractor is relieved. This feature prevents the unequal transfer of load to the two opposite lugs but I would argue that the stress relief groove already in place largely accomplishes this purpose. This is a academic quibble so I will bow to LMT in this respect. There is one additional feature that can be found in the bolt, but I am not at liberty to disclose the detail.

When considering wether to use the LMT parts one must consider the weapon. Correctly ported guns will derive little or no benefit from a carrier that is specifically set up to absorb excessive port pressures and some degree of residual case pressure. If not sufficiently gassed the reliability will suffer. This is not a fault of the carrier rather a mistake made in the application so be careful with simple substitutions. The bolt itself is exemplary. If not constrained by a $ value the bolt is a worthy addition to any rifle and will do nothing but enhance the durability of this part of the system.

Bill Alexander

As an engineer by trade it always impresses me to see detailed information such as what was posted here. Another reason why I enjoy this board.

I am interested in the long term reliability and parts sustainability of the entire 'system'. To this end I have adopted a mid-length gas system on a 14.5 barrel (BCM BFH). I have noted decreased bolt carrier speeds which in my opinion reduce stress on the moving parts in the system and therefore should increase parts longevity.

I am interested in the bolt due to the technical advantages and relatively non-existent disadvantages but am also considering the enhanced carrier as well.

Question is: Given a BCM BFH mid-length gas 14.5 barrel, H buffer and standard Colt carbine spring (with standard receiver extension) utilizing a wide range of available ammunition and weights how will the enhanced LMT carrier perform?

[Thomas M-4]

I use one in a 14.5'' LMT with a carbine spring and H-buffer.
I have about 4K through it give or take. Mostly XM193 & XM855
but I have put 100rds of wolf steel case 62 grain and 600 rds of 55 grain PMC Bronze. Wolf seems to be close to the edge but I didn't have any malfunctions with it. I had to replace the buffer spring around the 2K mark it fell bellow spec. Still going on the factory gas rings and they still pass the gravity check.

[Pappabear]

Huh, this thread raised it's head. I say after all this time, mine (the bolts) have run great on everything. Short long fat skinny barrels. I've not had problems.

You could justify the extra cash on the coating alone they clean real easy. I have to admit, I enjoy LMT coolaid.

[AR15barrels]

Question is: Given a BCM BFH mid-length gas 14.5 barrel, H buffer and standard Colt carbine spring (with standard receiver extension) utilizing a wide range of available ammunition and weights how will the enhanced LMT carrier perform?

You can have too much of a good thing.
Just like Lmt recommends against the use of the enhanced carrier on carbine gassed 10.5" barrels, you may also see similar short stroking issues on a mid gas 14.5" barrel.

[REDSKY383]

You can have too much of a good thing.
Just like Lmt recommends against the use of the enhanced carrier on carbine gassed 10.5" barrels, you may also see similar short stroking issues on a mid gas 14.5" barrel.

That's what I was thinking. I was thinking that I could compensate for that by using the AR-15 BCG rather than the M16 BCG (lighten it up) and go to a carbine buffer vice the 'H' buffer (further lighten the mass). But in the long run I may just go with the bolt and forget about the carrier.

[Tyrantresister]

The bolt is not ION coated I have never see that in any statement from LMT regarding the bolt?

If you read Bill Alexanders statement in this thread it explains the feature's of the bolt and carrier better than any other statement I have ever found.


Just what is the coating of the LMT bolt? It looks like chrome or nickel boron, or something similar?

Anyone happen to know? Surprising that LMT doesn't try to market this aspect of the bolt better to attract buyers considering the $150 price tag.

[Mr blasty]

Just what is the coating of the LMT bolt? It looks like chrome or nickel boron, or something similar?

Anyone happen to know? Surprising that LMT doesn't try to market this aspect of the bolt better to attract buyers considering the $150 price tag.

It's elctroless nickle.

[Mr blasty]

Any ideas how a 16" mid length with the enhanced carrier and bolt with a Vltor A5 stock would compare to a 14.5" mid length? Witch one would be "softer shooting"?

[Thomas M-4]

The carrier was optimized for the carbine gas system using a 14.5" -16" barrel. Anything other than that and you are outside LMT's specifications. So if it doesn't work for you outside of that there is nobody to blame but your self :sarcastic:
Now after saying that I have used it on a 10.5" barrel with carbine gas length system. With a suppressor attached it would lock the bolt back on the last round with out the suppressor it wouldn't lock the bolt back on the last round. I wouldn't bother with it on a middy gas system I think it would be too much of a good thing and you would be likely to have short strokes.

[Tyrantresister]

The bolt itself is of particular interest. The function of the dual spring extractor is frequently misinterpreted as an attempt to add spring force to the extractor claw. Rather it reduces the fatigue that the extractor spring(s) undergo by allowing the use of longer springs with lower K values; the % relative compression during the movement of the extractor is reduced. Remember that additional extractor force is not required now that the carrier is slowing the extraction cycle. The mitigation of stress in the bolt is accomplished in several ways. Material is the least visible change but is important to the design. The traditional Carpenter 158 is abandoned, being replaced by a significantly tougher grade from a different manufacturer. The lugs themselves are generously radiused between lugs and at the rear the diameter is actually reduced to allow a larger transition radius to be machined. The incorrectly identified sand cuts on the lugs are stress relief cuts. These allow any individual lug to elastically deform and give a smoother load over the contact patch. While this type of feature is very difficult to calculate and even more difficult to implement it helps to place the lug in a true shear load rather than amplify the bending moment. As noted the lug opposite the extractor is relieved. This feature prevents the unequal transfer of load to the two opposite lugs but I would argue that the stress relief groove already in place largely accomplishes this purpose. This is a academic quibble so I will bow to LMT in this respect. There is one additional feature that can be found in the bolt, but I am not at liberty to disclose the detail.

Bill Alexander

Bill, I only have one question for you. How do you think LMT's enhanced bolt compares to Denny's Super Duty bolt?

[Thomas M-4]

It's elctroless nickle.

This^^

[Tyrantresister]

How does electroless nickel compare to nickel boron?

[Mr blasty]

How does electroless nickel compare to nickel boron?

It's a good finish but in no way does it come close to the performance of NIB. I doubt you would be dissatisfied with electroless nickle though. If it wore off or you don't like it then just get it coated in whatever you want. It's still better than phosphate.

[Tyrantresister]

I think the main benefit of the enhanced LMT bolt is the mechanical design and not the coating. Things like the stronger steel, and the stress relief cuts, etc. are what makes it that much better / stronger.

[AR15barrels]

That's what I was thinking. I was thinking that I could compensate for that by using the AR-15 BCG rather than the M16 BCG (lighten it up) and go to a carbine buffer vice the 'H' buffer (further lighten the mass). But in the long run I may just go with the bolt and forget about the carrier.

The difference between M16 and AR15 carriers is so slight that it can be ignored, perhaps 1/3 ounce.

You should already be running a standard carbine buffer with a 14.5" midlength so there's nothing to be gained from switching from an H buffer to a standard carbine buffer.

[Waylander]

Sorry for the slight necropost but since this discussion seemed to revolve primarily around the use of an enhanced bolt in 5.56 (with the exception of a 7.62x39 post) I though I'd raise the question of how much this design would benefit the 6.8 platform?

If I'm not mistaken, LMT uses this BCG exclusively on their 6.8 rifles and I don't think they would be a company that would use it if it weren't warranted when they could use a less expensive BCG if possible. They seem for the most part no-nonsense IMO.

I know it's hardened steel but does anyone know if it's Carpenter 158 or 9310?

[TacticalSledgehammer]

What's the advantage of the enhanced bolt itself? Only the extractor and the cuts on lugs? Other than that would you say it's about equal to a quality bolt itself?

[Waylander]

What's the advantage of the enhanced bolt itself? Only the extractor and the cuts on lugs? Other than that would you say it's about equal to a quality bolt itself?

It's also hardened, nickel plated, and has less material taken out under the extractor like a standard bolt. Pics with the extractor removed are here.

https://www.m4carbine.net/showthread.php?t=1130

[PatrioticDisorder]

The LMT "lobster tail" extractors do not appear to increase spring tension, nor have I heard of anyone suggest they do.

I noted the decreased tension of the extractor (in comparision to the current SOCOM 5coil copper washed extractor spring, black insert, and Oring) on the LMT bolt, as it may be of concern if tried on the usual 10-11.5" uppers with their increased speed of recipication, esp with cans.

I really would've liked to see a lobster tail that used two standard AR extractor springs (captured) perhaps a wee deeper well to minimize spring compression.

Given the chance I would like to play around with this bolt, in a standard carrier, on a shorty.

I have a LMT enhanced F/A bolt group that was milled down similar to the Smith Ent "lightweight" chrome ones... just playing with ways modify the recoil impulse. It's really pretty, hah.

On an actual m4, with milspec ammo, the enhanced BCG appears to be a big plus. Two guys told me they had 35K and 50K+ on their BCG w/o issue.

I've been trying to research the LMT enhanced bolt, I'm strongly considering buying one for my DDM4V1 LW (carbine length), I'm strongly sold on the utility of the bolt, but what about the carrier, do you think the DDM4V1 would benefit from the carrier or would it potentially cause issues?

Also of relevance, Hornady TAP 75gr. .223 pressure is what I have for defensive ammo.

[Badger89]

I've been trying to research the LMT enhanced bolt, I'm strongly considering buying one for my DDM4V1 LW (carbine length), I'm strongly sold on the utility of the bolt, but what about the carrier, do you think the DDM4V1 would benefit from the carrier or would it potentially cause issues?
From what I have gathered regarding the LMT Enhanced BCG, the E-carrier seems to work well on most rifles, offering benefits for some configurations and functioning as a normal carrier on others. There has been quite a bit of testing done with the E-carrier by members much more knowledgeable than myself and multiple threads about it here on M4C. As for the E-bolt, it seems that quite a few members have had issues with the extractor springs not being stiff enough. I'm not sure if there is any way to remedy that... the E-bolt does seem to offer some benefits over a standard bolt, but benefits don't matter when you are having extraction issues. For those reasons, the general consensus seems to be that the E-carrier is GTG, but most of the members here run a standard mil-spec bolt with them.

[ZINCOGNITO]

Not being milspec is the only downside I found regarding the bolt. Any kind of maintenance makes it near impossible since parts are not readily available. I believe Iraqgunz runs the bolt carrier with BCM bolts but I'm not 100% sure.

[E-man930]

The new bolts do not have extraction issues and offer no downside.
They are also made of A100 and are nearly indestructible.

[DreadPirateMoyer]

The new bolts do not have extraction issues and offer no downside.
They are also made of A100 and are nearly indestructible.

When you say "new"," how new are we talking? I bought 2 since December and was hoping to know if I got a new one.

Also, mind if I ask how you know new ones don't have extraction problems?

[Badger89]

The new bolts do not have extraction issues and offer no downside.
They are also made of A100 and are nearly indestructible.
When you say "new"," how new are we talking? I bought 2 since December and was hoping to know if I got a new one.

Also, mind if I ask how you know new ones don't have extraction problems?
I would also like to hear more about this, as I know Iraqgunz and others run the E-carrier and a standard milspec bolt. Where are you getting this information from?

[PatrioticDisorder]

I would also like to hear more about this, as I know Iraqgunz and others run the E-carrier and a standard milspec bolt. Where are you getting this information from?

That's why I posted, information is a little scarce on this bolt. I've read about problems in the past but last reported problem I've seen was years ago and I know it's undergone some revisions. It was my understanding the bolt is good to go.

My question on here was more or less geared towards the carrier and if it would benefit me to run it with my DDM4 being carbine length, but I suspect the DD is not overgassed so I probably won't even try to run the carrier unless I run into issues.

[Iraqgunz]

I agree with Danno about the extractor springs. Though they appear fine, I prefer a nice solid enhanced spring and something that is readily available.

I have 3 different ARs now with the enhanced carriers and standard bolts. Both SBR uppers and my 20" rifle.

[PatrioticDisorder]

I agree with Danno about the extractor springs. Though they appear fine, I prefer a nice solid enhanced spring and something that is readily available.

I have 3 different ARs now with the enhanced carriers and standard bolts. Both SBR uppers and my 20" rifle.

Does LMT not provide spare parts kits for their enhanced bolts?

[ColtSeavers]

Does LMT not provide spare parts kits for their enhanced bolts?

A cursory glance at their online store only shows complete bolts.

http://www.lmtstore.com/bolts-carriers-groups.html?limit=all

[PatrioticDisorder]

A cursory glance at their online store only shows complete bolts.

http://www.lmtstore.com/bolts-carriers-groups.html?limit=all

Yes, this is why I ask the question, but one would think it would be good business for them to sell spare part kits. Not doing so would turn off potential buyers including myself...

[E-man930]

It is hard to say when LMT last updated their bolt, but I have run them since the end of 2011 and have not had any issues in 10.5 / 11.5 guns both suppressed and un-suppressed. The extractor tension is almost identical to my KAC E3 bolt with KAC's current gen extractor and springs. I would be game to create a LMT E-bolt graphic much like I did for the E-carrier if enough people post up some pics of their bolts along with the markings engraved on them. Perhaps we can unravel the progressive changes together... Also, I think LMT dealers can get the springs and extractors separately; I think I ordered my spares from Operation Parts.

[dhena81]

Operation parts has the enhanced bolt extractors and springs for sale.


I've been on a waiting list for a couple of things there including the complete E-BCG and they sell a SA E-BC without a bolt but not the FA for whatever reason. Either way I have a spare JP bolt and depending on the configuration that arrives in the mail first I'll play around with the two different bolt combinations in the enhanced carrier.

[ABNAK]

I bought mine from a Quantico Tactical store about a year or more ago. I then called LMT and ordered an extra extractor. It did not come with extra springs so I'd need to salvage those if it broke, which is highly unlikey.