Home Forums Hunting & Shooting AR and Tactical Rifles Couple of lessons learned

I was a part of an AR class this week. Twenty students, a bit over a thousand rounds apiece. Couple of observations....

An Aero Precision home build had a lot of problems. Something in the trigger (somebody else looked at it and I forget what it was) broke and the gun went full auto on day two. The gas key staking was abysmal and the key worked loose on day three. And the extractor lost tension on day four. The extractor spring was visibly shorter than the new replacement by a coil length and could be compressed with moderate finger pressure. The BCG and LPK were both AP, those problems are on them. The gas block also came loose, that's the fault of the builder. Don't forget to loctite set screw gas blocks.

Every gun with extraction problems during the week had carbine gas.

Most people can shoot better standing than kneeling.

Once people understand how ARs actually work, they immediately buy into the idea of quality parts.

Edited to add:
Cheap Vortex optics continued their 100% fail rate. Every single one of their cheap red dots have failed over the course of a week. One Sparc2 lasted until lunch on the last day, then rattled loose from its mount.

Thanks for the update! Always appreciated.

Why anyone would put anything together without loctite, preferably 640 where the screw can then fall out and it still won't move, is kinda beyond me. I know if i ever get to building Carolyn and I a pair of vehicle guns, they sure won't be anything but solid.

You don't alwyas have to have the best parts, but you do have to know what to look for and how to assemble when building. And you do need to know which parts HAVE to be good. Extractors are NOT the place to skimp.

Keys will stay in place without staking if 640 is used...

Kneeling sucks UNTIL you kind of figure it out. There are some important parts to learn on kneeling or it IS worse than standing. Ball of the knee to ball of the elbow is one of the big killers.

A shame to know about Vortex, the binocs Carolyn has are just really good glass for what they are and what they cost. Never had an issue.

Have never bought vortex scope or dot, and you indicate why thats been a good decision so far.

Be interested to see if you contacted them and told them what you are seeing, if they would beef up and send you a few to torture test... it does happen as you well know.

Have a great weekend. Heat sucks already but what can I do... just keep dreaming of mile marker 1402.....

I've got a pair of their binos too, I think they're Diamondbacks. I've been very impressed with them.

I know a lot of guys who use the Razor line of scopes, specifically the 1-6s and they all love them. But I think Vortex relies on the popularity of their really good stuff to sell their really crappy stuff.

Yeah the heat sucks.... A/C went out last weekend, but I got a buddy deal and got it fixed for free and got the A/C hooked up and running on the addition.

Doesn't surprise me about the low end Vortex optics. I don't trust anything they make other than the Razor line, which is very nice. Even their PST scopes seem to have an abnormal amount of issues.

Thanks for the info, Blue.

Not too surprised at the Vortex failure.......... & I don't have any Vortex.

Also, mildly surprised at the AP's BCG failures, but I don't consider AP as anything more than lower mid-range product & other than a lower of theirs that I've used, I don't use anything else from them.

In the long run, using premium components doesn't absolutely guarantee success but I think it surely increases the likelihood of it by a significant amount so in the long run, less grief & not that much more money expended either. If cheaper parts have to be replace, likely the end cost or premium parts is actually a better bargain.

MM

Bluedreaux,

That is some quality information - Thanks. I am brand new to AR's and am trying to figure out which parts to use. After reading your initial post, I have quite a few questions:

What trigger were you using? What after-market trigger would you suggest for general plinking and possibly hog/deer hunting sometime in the future?

Whose BCG would you recommend? I have been leaning towards the Sionics NP3 coated unit but am open to another brand.

Do you recommend using Loc-Tite on CLAMP-style gas blocks? Seems like this attachment type is more secure than the set screw configuration.

Mid-length gas over carbine? I am going with the 277 Wolverine cartridge, so heavier bullet.

Whose LPK would you recommend?

What red dot would you suggest?

Thanks in advance.

I used a CMC 4.5# this week. For what you're doing, if you didn't want to just use a stock GI trigger, I'd get an ALG ACT, BCM PNT, or something similar. They run about $50.

My go-to for BCGs would be BCM. Look for an 8620 carrier and 9310 bolt. HPT and MPI is a sign that they're checking for quality. I haven't used any of the Sionics stuff, but the guys running Sionics know what they're doing and I've only heard good stuff about them. Even the Aero BCG that messed up this week would likely have been fine for a very long time if the spring and staking had been fixed before it was used.

I'd loctite either kind of gas block. With whatever loctite Jeff recommends. And I'd use a set screw over a clamp on style. They seem less prone to leakage and more stable / easier to line up if the barrel is dimpled.

Mid-length gas is usually a better idea. Most ARs are over-gassed. Mid-length systems can help that.

BCM, ALG, Colt for LPKs.

Aimpoints are the go-to answer for dots. I prefer an Eotech, but they can have problems. For your uses you'd be better suited with a 1-4 optic. There are several threads here on them.

Also, I'd really, really, recommend that you get a 5.56 gun. Wildcats can be problematic to gas properly and tracking down problems with loading and gassing isn't as straightforward because not many folks have experience with them. And in the field they offer very little real advantage. Figure out how to build and what you like with the 5.56 and then go from there.

Appreciate your thoughts on triggers. Had been looking at the basic single-stage Geissele but will give these others some thought.

The Sionics BCG is made from Carpenter 158 which, by all accounts, seems to be a high quality steel. The gas key will be staked from the factory but is there anything further I can do to reinforce it?

Probably does not matter but I am going with an adjustable gas block. Will use Loc-Tite.

Too far along with the 277 Wolverine at this point. The nice thing is that I can just swap a 223/5.56 barrel and shoot that ammo with no issues. The 277 is based off of the .223 and uses the same bolt, mags, etc.

Which Geissele are you looking at?

The Sionics will be staked fine. If it's not they'll fix it.

Besides what Blue has recommended, & especially since you are going with a wildcat, I'd also add that I strongly suggest an adjustable gas block & it doesn't get any better than SLR's version, IMO.

Gives you more flexibility if you are over gassed & I strongly prefer adjusting the gas than buying & trying several different spring & buffer combinations.

An H or H2 with a standard or enhanced spring & adjust gas as you need to.

JMHO

MM

Good info bluedreaux. I'm not surprised at all by the Vortex going to chit. My buddy had the Viper PST on a short mag and it didn't last very long. We both swore off the POS's after that... I have a question regarding the gas block: Aren't most of the good ones considered "bomb proof", where the barrel is actually drilled and a pin put in to hold the gas block in place, with the addition of the typical set screws??? My 3 ar's are built this way.. The other comments on Aero Precision are good to know as well, but I'm wondering if it was more of a novice builder mistake that anything else??

Pat Rogers used to keep track of this stuff and shared it so folks would steer clear of parts with a bad average.
Looks like nothing has changed.

Now wait for someone to say their brand x has never failed and parts is parts...

As for loctite, 640 is bearing retainer not thread locker. Don't use it on anything you wouldn't put a torch on for removal.

Yes, the best method is to install the gas block with taper pins. It's essentially a structural part of the barrel at that point and is as solid as it can be, short of welding it on.

The trigger, gas key and extractor spring are all AP's fault as far as I'm concerned. The parts just failed.

Was just about to post... but you covered my tail once again. 640 will come off eventually. Last front sight base I put on many years ago that I needed off, pulled the set screws, then heated with propane torch and between that and a 2x4 and a 3 pound sledge with the barrel clamped in a vice it came off again finally...

But if you use 640 I'd be WAY surprised if you ever had an issue with stuff coming apart. AMU units have used it for years due to this...

Blue, I have a Colt 6920 with carbine gas but most of my guns are DD mid length gas. Did you see Colt's or DD guns fail? I have two cheap SIG Romeo 4's I wish I had not bought and use these on guns that are not serious. Any scopes used and failed at the course?

To further this, which I"m often to much of a hurry to do...

IF you have NO clue how an AR works and how to assemble, then by all means buy the best you can afford with the best parts! Thats the only way to do it.

And RE the 640.. I use that on sight bases for years but used other either blue 242 or green something to set the screws with. The 640 went on the part. I would put it on carrier key screws though, the 640, if they were not staked. Certain things can benefit from 640 big time, other things if you need to take them apart, like a small screw later on, you'll likely just strip the head before the 640 releases.. unless you get it really hot first...

Just FYI on being careful with where you put 640... on a bolt gun, bases to gun probably ok, ring screws... nope, 242 has never failed me there and you may need to replace the scope at some point... hence no 640 for me on certain parts.

Sorry just re-read, any SWFA scope failures, Leupold, any others besides vortex red dots and scopes?

There was one home build with a DD barrel that ran great. About 8 factory Colts that ran fine (all carbine gas).

A Steiner 1-4 and Leupold VXR1.25-4 were used and there were no problems from either of them.

Both of the Vortex dots crashed. The Aimpoints and Eotechs were fine. One non-F-marked FSB had elevation problems because Bushmaster refuses to put proper parts on a gun.

Thanks for your information! That Steiner 1-4 keeps popping up!

Carbine gassed guns, built right, run just fine. Mid length guns with a larger than needed gas port will still be over gassed and be hard on parts.

I shot today with a friend who has a PSA mid length M4, I shot my Colt pencil barreled carbine gassed gun. We started out shooting offhand at 50, kneeling at 75 and prone using the magazine as a monopod at 100. M193 ammo, he shot a red dot, I shot my 1-6 FireDot on low power to keep it fair. His gun runs fine but throws brass at 2:00, mine at 4:00. Time will tell how his will hold up but it bugs him enough, he's ready to try an adjustable gas block. Extra power buffer spring and H2, even 9mm buffer didn't help.

True mil spec works.

With all the money people "save" on their budget builds, you think they'd carry a spare BCG when they go to a class. Makes for a quick fix for any of many several common problems.

They probably don't carry a backup for the same reason they used a cheap one in the 1st place.

MM

Bluedreaux, were there any other brands notable for reliability or failure?

As a trend Colts, DD and BCM are always good. Radical and Underground Tactical are trash. Nobody cares more about your build than you do, so double check everything.

Thanks. Pretty much what I figured.

I wonder where the Rugers fit.

I have seen a couple of posts on this thread that emphasize using the best parts possible. I am puzzled by those who would not do so. Why would you NOT use the best available parts/components, for any gun, not just AR's? I will concede that "Best Quality" is somewhat subjective but knowingly using inferior parts, just to complete a gun, will always be a foreign concept to me.

From what I've seen most people don't know what quality is and equate name recognition with quality.

And when you try to educate them they either don't believe you or don't believe that it matters.

I've never seen a Ruger in person.

And when that "quality" costs more, many just simply won't pony up; they cut corners & knowingly or not, settle for something less.

MM

Colt, DD, LMT, BC, LaRue, KNS, Geisslee for parts.
Lowers I am not 100% sure how much this matters with a good parts kit and good trigger?
Uppers do matter to me more DD, Colt, VLTOR, BCM,YHM

Here is a question for you...does anyone know if the anderson lowers are the same hardness as a Colt lower? I kind of regret building a gun using an Anderson lower back during Zero's reign and wonder if it will wear out faster?

Once you build a quality AR using quality parts, it's easy to understand why one gun costs $500 and another $1200.

"Here is a question for you...does anyone know if the anderson lowers are the same hardness as a Colt lower? I kind of regret building a gun using an Anderson lower back during Zero's reign and wonder if it will wear out faster?" from jimmyp.



I suspect it will take a lot of shooting to wear it out.

I have a lower that I built on back about 1976 or '77 that was by Scheutzen Gun Works (that somehow morphed into Olympic or Olympia) and it was machined out of 6061 aluminum that is supposed to be softer than 7075 or whatever they're using nowadays. It's still fine. Doesn't get shot much anymore. The only reason I found out it was the softer alloy is that I had it refinished (re-anodized) and the anodizing processes are a bit different I've been told.

Back when I was taking classes it worked, and a Colt or two I had worked. I never saw any need for anything else. Have them, just don't see that BCM or DD is better than Colt.


Not that it matters but the build might have been a few years later.

"Back when I was taking classes it worked, and a Colt or two I had worked. I never saw any need for anything else. Have them, just don't see that BCM or DD is better than Colt."

They aren't. But they are way ahead of the cheaper guns.

I do think it would be nice to have a midlength gas system from Colt.

Having mid lengths from Krieger, Noveske and LaRue , comparing carbine gas from Colt and DD, I just don't think it makes that much difference but here you go...
http://www.colt.com/Media/Press-Rel...-Carbine-Featuring-Mid-Length-Gas-System

I think the Andersons are 7075 and Mil spec anodized but that is what they say, have no idea if it's the truth

Colt 6960. TALO dealers. Thanks.

add: After looking at Slickguns with prices $1150 and up, I may just replace a barrel.

Ya, I like Colt Defense, Colt Mfg. May not be up to specs but a new barrel is always a good thing.

Determining if the carrier staking is adequate is easily assured with a punch. I had one that appeared staked with beautiful punch marks but the screws turned freely despite that.

You will not wear out a "softer" lower in your lifetime....trust me on that. The two lowers I have that had sloppy pins were... a colt... we swaged those holes a bit by the USMC AMU team armorer and I've done it to one other lower, that is the only Oly lower I have. Both have seen a LOT of rounds down, well lets just say at one point I figured we had shot about 250K rounds at one point... I figure 5K per barrel give or take... and I know both the Colt and the trash Oly, have at least 35K rounds on each one. I don't know many folks that will put 35K rounds on a single AR in their lives unless specific competition...

I'll go back to basics.. yes you have to have good parts. They do not have to have a single specific name on them. You need a better trigger and the best barrel... between those you'll have a top line gun capability wise, regardless of if perfectly mated and paired colors or frankengun looking...

But for those that don't know what it takes, buying brand name of the big names as noted by Blue and TWR and others sure never hurts reliability.

Rost495, your experience definitely trumps internet conjecture. If you had to purchase a rifle, what would you choose based on price range? Say < 800, 800-1200, > 1200.

I am planning to build my first lower and ran across this thread.

I bought the following items:

Aero Precision lower from Creedmoor
Parts kit and stock from White Oak Armament
Geissele Service Rifle trigger from Primary Arms.


First question is, even though they are already purchased, are there any issues with the parts I have purchased? I own other Geisselle triggers and have been happy with them and it is my assumption that John Holliger would sell good parts.

Second questions, are there any tricks or tips for assembling a lower.

Any input would be welcomed.

And this lower will be used for Highpower competition if everything works out well.

Sorry I can't answer. I wouldn't buy a rifle. I still have probably another 15 lowers somewhere in the safe.

I don't care what lower. I don't care what upper.
I do care what trigger, RRA Varmint for most non competition applications, yes I may even have to tune it a bit. Beyond that its going to Geiselle, Millazo or such.
Barrel I care very much about. If I care about barrel life I go cut only... buttons do NOT last as long.
Make mine floated. You pick how.
Give me an A1 or A2 stock, I've shot standard stocks so many years in competion, I need nothing else.

And a good set of internals... brand I could care less about, quality yes, likely why I've tried to buy all my LPK from White Oak, sans teh triggers....IE I"mnot paying for a mil spec crap trigger.

Any other bells and whistles are up to you. I can do just about anything I want with the above, and if I don't kill or win, its me, not the gun.

IF I were to buy guns just for.... I"d buy whatever is cheapest, and just go through the internals... a cheap gun with a newBCG and new LPK is still going to be cheaper than one of the brand name ones generally.

All of that said, if forced into a corner, I'd buy a colt first, trash the trigger for sure, and expect 1.25 or so MOA. And I might even be surprised.... this if I was forced to buy a gun I expected to not have to work on at all.

Let me add one more thing, if it was a gun for 2 leggeds, I would buy or put together only the better parts, sans names, and then the ONLY way I'd trust it is to beat it up, after 500 or 1000 rounds I"d know whether I"m going to trust it or not. And I'd be betting a total stock Colt would never let me down. Even though I can never see me owning one such gun. Stock Colt that is.

Trigger issue. Someone tried to do a trigger job by lessening the engagement on the sear. This is the reason why if you want a better trigger, you buy a better trigger. The sear engagement between the hammer/trigger is critical on an AR because it has to do with disconnector timing. Lessen the engagement and the disconnector has issues catching. Little problem and the gun will double, firing when you release the trigger. Big problem and you get hammer follow through, which will give you a full auto burst, but it's completely unsafe; you can get a round firing out of battery.
Extraction problems, especially with carbines. The carbine length gas system has very high port pressure and that has caused problems from day one. L. James Sullivan said he wished they made the cut for the extractor spring deeper/bigger, but they didn't foresee the carbines. The carbine gas system solution is to use the late style carbine extractor spring. The interim fix was to slip a rubber o-ring in with the spring; you'll see that on some Colt's and some govt AR's. The high port pressure caused the gas to hit the expansion chamber in the bolt with such force that the extractor actually bounced before it began its travel rearward. On rare occasion, that bounce will cause it to jump the rim (usually on full auto, but happens on semi from time to time) and the bolt rides back leaving the case in the chamber. PIA of a jam to clear in the field.

There's no doubt that the extractor tension needs to be correct, whatever method you choose, but the best solution is an adjustable gas block. End of problem with over-gassing.

MM

No doubt. AR's are also a bit notorious for gas port erosion...solves that issue too.

Interesting on gas port erosion as I've shot a few rifle length tubes to over 12K rounds each, and could tell no difference related to gas volume than when the barrel had 1000 or so rounds on it. Probably helps the ports were the correct size to start with...

The trigger was unaltered from the factory (an AP LPK).

Triggers aren't all the same even if it says so. Good parts equal good service.

I'd sure like to know how an AR can fire out of battery when the firing pin can't reach the primer until the bolt is locked.

Start with the correct size gas port and a good quality extractor/spring kit and you'll eliminate problems from the start.

I've both carbine and mid length gas and find it impossible to tell any difference while shooting. Build em right and they will run.

in 39 years of shooting black rifles I can only recall haveing had one jam and it was from some off brand steel magazine, which I immediately destroyed. I have no idea how much 55 grain ball ammo I have fired over this time. I have never owned a diamondback, core, windham, PSA, etc. I promptly sold a RRA and Bushwacker as soon as I realized what they were. Colt or DD are good guns, Noveske is a good gun, BCM is great, wish I could afford knight. People buy crap and complain when it breaks.

You must be a pretty insensitive kind of guy...................

MM

Good info. Thanks.

Man, I wish I had your luck!

...still...I have never had a problem with a Colt AR which is why the vast majority of AR's I have owned over the years have been Colt's. When I got my first AR back in the '80's everyone gave me a hard time and told me to get used to clearing jams...yeah, NEVER had an issue with that old SP1. Meanwhile watched the Mini-14's have various failures from time to time when they got good and hot. I recall my friends rather expensive H&K 93 giving him a little trouble here and there while my SP1 just hummed along. My AR-180 was bulletproof too...like a fool I sold it, but recently fixed that bad decision. But over the years I've had a few lemons for sure.

I find myself fixing a lot of AR's for 3 gun shooters and just like 1911's & Glocks, you find many of the problems are owner induced.

I keep tabs on what my friends own, and in my close circle I have noticed pretty good results with Colt, Bushmaster, and S&W for the more affordable AR's. I know one competitor who has put probably close to 20k rounds through a Spikes Tactical in a little over 1.5 years, and he hasn't had any issues...I'm pretty surprised at that, considering what he paid for it.

The more I read this thread, the more I realize just how much I know (or don't know) about ARs. I wish I had half the experience that some of you guys have.

Meanwhile, I will continue to accumulate parts and enjoy putting them together.

Just for gits and shiggles if nothing else.

many who don't lubricate their firearms have worse luck than others. My ar's smoke when I shoot them from oil evaporation or burning off. Same with tight fitting 1911's. Then again a long time ago I learned that blue steel will rust in humid climates and gas guns with rusted chambers don't work.

I do clean them once every 800-1000 rounds or so, once in a while I will clean a barrel too. CLP and now slip2000EWL or just any oil I think.