Jax, I am bowing out. I was just replying to what was directed at me, and was not aware of this whole history or threshold that was never alluded to in the thread.
How the **** would I or anyone else just know why you made this thread? Should I search every post you ever made just to ensure I have the absolute best understanding and context of every current post you make? Ok, BRB, going to read your 1600+ posts, Yea NO.
I don’t need you to spoon feed me bullshit about some parts game that I could care less about. Don’t cop an attitude when you are the one who is not communicating clearly.
Next time, be clear with your words and intentions. Perhaps referencing the thread or atleast MENTIONING it in the OP would prevent confustion or agrivation. Don’t expect everyone here to be mind readers.
Which is why I personally recommend letting the parts mate before polishing.
And by polishing, I don’t think anyone is suggesting taking a file to anything. The amount of material removed while polishing (if done properly) is probably microscopic.
Bingo.
Not a necessary Mod.
Can help improve reliability if the gun is operating at the edges of reliability depending on gas system and buffer weight choices.
No material is being removed, so if you want to spend the time to do it, you won’t hurt anything unless you use an abrasive grit and get to aggressive with it.
If you just don’t have the time (me) or feel like it’s an unnecessary step, then don’t worry about it.
Everyone take a step back from the computer and breath. For the record I have never had to polish any BCG for it to run smooth. I have 3 separate uppers that all have LMT enhanced carriers and all of my carbines have A5 tubes and have yet to experience a single malfunction.
You have obviously not been paying attention to the multiple Vltor A5 threads where this process was recommended to address specific situations with regard to weapon setup.
Feel free to not polish anything on your gun. Your comments are duly noted.
I must have been under a rock.
Why is this necessary? Seriously – I don’t know.
Don’t have and don’t use a Vltor A5. I know the Marines do on their 20-inch/collapsing stock M16A4.
I think “grab a dremel” was a metaphor. SpeedRacer isn’t a hack who dremel’s his shit. Proper polishing should not result in enough dimensional variance over usage to really matter. But it still will be “different” as you note. I am not a fan of it. I view it the same as taking apart the differential on a new vehicle and hand-lapping the ring/pinion teeth. Who the hell does that?
Jaxman probably has the first example of a 14.5" middy running one of the heavier A5 buffers with an LMT enhanced carrier. The gun was the smoothest he’d ever used, yet it would fail to lock back on empty on occasion. So, I advised him that, if his LMT E-carrier was as rough as mine, polishing it was of quantifiable benefit. This might be more than a year ago. Since then, it’s been discussed in several threads up to, and including this one:
https://www.m4carbine.net/showthread.php?147696-Vltor-A5-Still-a-must-have
After polishing as instructed in my OP (and which I relayed via PM to him quite a while ago), Jax observed that his issues had been resolved and several others have since shared his experience. In the above listed thread, the topic came up again (for the umpteenth time) and, again, requests were made for instructions. Thus, this thread.
I guess no good deed goes unpunished? (not directed toward you at all)
Let me ask a simpleton question…WHY are some LMT carriers rough? Was it a mistake, or were/are they made that way for a reason, and if so why? Are they still like that? Would LMT send another if one was unhappy with a rough one?
Outstanding question and one that I’ve often asked. Eman has a thread on generational info for the E-Carriers (I think they are in their 5th generation) and he would likely be the one to ask…
The 2nd Gen carrier I have in my wife’s BCM is butter smooth, just like a Colt. As Mark noted, the Colt carriers (and every BCM I’ve handled) are remarkably smooth in their finish (and the metal underneath seems to be very well finished as well). The LMT 4th gen has a ridiculously coarse phosphate finish and even the metal underneath is visibly rougher than any other carrier I’ve ever seen. I don’t know if that shows up in my photos, but it is readily apparent to the naked eye and there is a huge difference in how it feels as you hand cycle the gun. Even when dripping with FireClean, it still felt there was sand in the action of my carbine.
EDIT: Linky.
https://www.m4carbine.net/showthread.php?125899-LMT-Enhanced-Carrier-Technical-Comparison
Thanks BufordTJustice-
I meant to add, the bcg in my LMT Defender is vey smooth, was like that when I bought it new several months before DIPSHIT got elected the first time. Just STRICKLY guessing & tossing it around in my head…maybe the roughness holds
lube better…or something? GOT to be a reason, I cant see LMT making a “mistake” like that, for so long even.
Also, after seeing the pics in your link…thanks, btw…I just have to ask…WHY?!! If something works, WHY keep bringing out different styles/models? Like Glock…for example. Had a great pistol, made changes that screwed up an excellent, well earned rep. WHY are there so many different types of bcg’s when we could all live nicely with just a few? IMO, of course. Thoughts anyone?
Thanks
For some reasons the Gen 4 E-carriers had a really textured park - and created this tough finish all over the unit, to include the bearings.
If you have a Gen 4 (and I had 3), I would take Buford’s advice and polish the bearing / carrier contact surfaces. I did it to 2 of my Gen 4s with noticeable improvement to how smooth it cycles.
The Gen 5, Gen 5.5 (I need to update my chart!) and the previous Gens all had a fairly smooth finish that didn’t really see as much of a gain with this mod as a few hundred rounds polished up the contact surfaces quite nicely. Hope this helps…
I think the miscommunication here is that some are coming to believe that more material will be removed by buffing/polishing the contact points than would be through shooting a few thousand rounds. What I understand is really happening is the buffing/polishing process explained here doesn’t actually remove any excessive material from the carrier, and smooth’s the contact points more thoroughly than just firing it. In turn, aiding in the reliability of firing underpowered ammo with a 14.5" middy w/ a A5 system using the heaviest buffer possible.
For the people who have not read the threads about a 14.5" middy w/ the A5, this process is not really needed whatsoever with running a standard carbine RE on any rifle. Only suggested for the 14.5" middy and A5 when wanting more reliability with underpowered ammo.
For anyone reading this, this process is not needed except for the aforementioned. Your rifle should be gtg, don’t sweat it. We don’t want to fuel the LWRC and piston fanboys with thinking this needs to be done to make a DI run as reliably as their “piston” rifles.
I just sold my 16" middy upper to get a 14.5" middy upper (I wanted a KMR rail but getting a whole new upper was cheaper as I also wanted a 14.5" too) and I just bought my self a A5 RE and a A5H0 buffer + green Springco spring. I plan to set it all up and run through various ammo and work my way up in buffer weights until I get consistent reliability with underpowered ammo and the heaviest buffer. I am looking forward to seeing how well it goes.
Only suggested for the 14.5" middy and A5 when wanting more reliability with underpowered ammo.
Reading the thread title and original post I’d have never figured that out and was wondering WTF. 14.5 mid, an A5 RE, a heavy/very-heavy buffer, and under-powered ammo. Gotta be somebody’s idea of a bad joke.
Rough texture finish or not the shorter bearing surfaces on the (Gen 3-5) LMT enhanced carrier should reduce overall friction.
I am going off of the information I have read here. I have yet to get hands on (will soon). I have a BCM bcg, I am going to wait to try the buffing/polishing until after trying a variation of ammo when I install an A5. For all I know, I might not need to.
That’s not the only setup that benefits from this polishing. My Rainier Arms mountain series 18" with rifle gas also benefits from the polishing. In fact, ANY upper that is not over-gassed can benefit from this mod, because it allows you to move up in buffer weight without sacrificing reliability.
Could it also apply directly to sr15’s? Don’t know until we try.
I am telling you from extensive first-hand experience that the gen 4 carriers (of which there are many in use on this board) are so rough that they may never self polish. And, waiting for this change forces ether user to use a substantially lighter buffer than they would otherwise employ…needlessly increasing gun movement and speeding unlocking with no benefit OTHER than the user being able to say that they didn’t polish anything.
For carriers that aren’t finished like 60 grit, sure it probably isn’t necessary. But lmt shipped a LOT of those coarse carriers. In fact, all my local buddies ended up with one of the gen 4’s.
EDIT: As for non gen 4 rough finish carriers, what this amounts to is simply accelerated finish wear. No harm to it and no cause for alarm if somebody decided to skip putting several hundred rounds downrange to work the finish on the carrier smooth.
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This is exactly why I chimed in. Newer/novice shooters who now think they need to take a dremel to perfectly serviceable gear to make it run. This post is a glaring example of the type of ignorance and missinformation that is soon to spread.
IG already TOLD you about that crap.
Thank you for chiming in, Eman. If you’re able, I hope you can continue to update your E-carrier thread with gen 5.5 info.
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