Obtaining and Maintaining a good AR-15
January 3, 2020 at 1:53 pm #135048
I think in light of recent events, we should re-visit a few things in regards to rifle purchase, set up, and use. First of all, I have usually been the guy who recommends building up your own, from various vendors. Due to many issues, including varying parts QC, gunsmith competence, and rapidly changing threat levels, I no longer recommend this course of action. Instead, I recommend finding a factory-built rifle, either Colt, BCM, Daniel Defense, LMT, or Geiselle. There are a few others that some might consider (and rightly so), but I don’t want to get out in the weeds here. This gives you 5 brands to choose from, that you should be able to source something, from a stocking dealer, and be ready to roll, in a short period of time. And that’s the key point here. We’re talking about rapidly moving events, which if you’ve waited this long to prep for, you’re already behind the eight ball and need to catch up, quickly.
The only exception to this would be if you have access to a competent gunsmith, who can help you obtain and build a rifle from these, or other parts. But I’ve found this is a big ask sometimes, and most folks don’t have this kind of resource readily available. So when in doubt, see paragraph one.
Regardless, you need to have a technical check and inspection of your rifle. And I really don’t care where it came from. If it’s designed and built by humans, something can be off. If it’s a mechanical object, it can break. Here is a short list of things to check. A competent gunsmith will do all this, and more, but at least make sure this is all done.
First off, have the chamber gaged. You want a true 5.56 chamber here. You might be surprised how often this isn’t the case. A few turns of a chamber reamer can make all the difference between smooth runnings and aggravation in the extreme. Especially for true 5.56 ammo, which you want. I’m gonna ASSUme you have a new bbl so no need to erosion gage check it.
Check the torque on the bbl nut. Again, lots of surprises here. Make sure it’s within range and on the high side, if necessary. Most go low and that’s where problems begin. (Pro-tip: better yet, get a Free Float rail and a new bbl nut without notches to worry about lining up.)
Now check the gas block. If you go low pro, make sure it’s locked in place (Pro-tip: dimple the bbl for the lock screws and locktite into place, once rifle is proven.)
Add new flash suppressor as required.
Check the BCG. Make sure keyway is staked. This isn’t the problem it once was but still check. Disassemble bolt. Inspect/replace extractor, ejector assemblies, gas rings, cam pin, and firing pin. Make sure firing pin protrudes after assembly(!). (Pro-tip: there’s actually a gage for this.)
Replace Charging Handle with BCM Medium latch. This is actually important with the modern technique.
Inspect/replace buffer spring.
Make sure buffer collar is staked in place. Two places preferable.
Inspect/replace LPK. Make sure all springs are new and sufficient tension. Make sure disconnector works properly. Make sure safety works properly.
Insert unloaded mag. Make sure mag catch works properly. Make sure bolt catch works properly.
Make sure grip screw is tight.
Add/change out any furniture as required.
Add RDS or other optic as required.
Take to range. Insert one round in mag and perform safety checks again. Fire off round. Make sure of good function, including bolt lock back.
Zero all sights.
Return to base. Clean rifle. Locktite all accessories once rifle is set up and proven.
Return to range until you’ve put at least 500 rds through it. Inspect again for any issues.
I’m sure I’ve missed a step or two, so feel free to add to list. The point being with a factory rifle from above vendors, your rifle will probably sail right through this inspection and testing process.
Yes, you probably spent more money than that special down at Billy-Bob’s gunshop, or that little deal at the gunshow. Yes, you spent more money on a gunsmith checking out a bunch of stuff that should have been down right at the factory. With any luck, you might find a competent gunsmith that can both order you the rifle, and inspect it himself. So you might be able to work that into a package deal.
January 3, 2020 at 3:58 pm #135058LittleBigBillParticipant
Great post, thank you!
January 3, 2020 at 4:22 pm #135059MarkParticipant
Good post! It’s very helpful.
January 3, 2020 at 6:29 pm #135073
Here’s an example of exactly what I’d build:
Colt 6920, or equivalent rifle, 16″ nominal bbl, carbine gas
RDS: EOTech EXPS3, or equivalent
BUIS: MI Combat Rifle set, or equivalent
Rail: MI Combat Rail, one inch shorter than bbl
Gas block: MI low pro or equivalent, dimpled into bbl
Charging Handle: BCM mid-latch
Buttstock: Magpul CTR
Grip: Magpul MOE
Sling: Viking Tactics two-point, with Magpul QD swivels
Flash Suppressor: AAC Black Out flash hider, or equivalent
Extractor O-Ring: Crane (Carbine gas)
Buffer: H2 (Carbine gas)
Light: SF Scout 600 series
Mount: Arisaka Offset Scout m-lok
Pressure Pad: SF
Mags: Magpul Gen II (at least 12)
Ammo: M193 55 gr training, M855 62 gr Green Tip war rounds (shit at least one case each, to start)
Cleaning kit: USGI or equivalent, plus .223 cal bore snake, 1″ paint brush, and multi-tool
Oil: Slip 2,000 or equivalent (6 oz to start)
Firing pin & retaining pin
Complete spare bolt
extra extractor ass’y
extra ejector ass’y
extra set gas rings (2)
Hammer springs (2)
Trigger springs (2)
Disconnector Springs (2)
Buffer spring (2)
Crane O-ring (2)
Lewis Machine and Tool
Advanced Armament Co
January 3, 2020 at 7:49 pm #135081
Once you are up and running with a reliable rifle, it doesn’t stop there. Besides obvious expendables, such as ammo, mags, oil, etc. you need to think about some kind of maintenance or sustainment plan.
Starting with pre-combat checks:
Nothing obviously fucked up (bent bbl, broken optic)
Rifle oiled, dry fire function check
Check tell-tale lines on all bolts
Optic working, fresh batts
Light working, fresh batts
Sling/swivels secured, running ends taped
Mags loaded, serviceable
Load up hot, brass check, mag check, optic on and adjusted
Monthly check or 1K rounds:
Inspect complete BCG for cracks, worn parts, etc.
Inspect bore and chamber- clean and bright, no scarring
Inspect fire control parts, check spring tensions, wear, cracks
Inspect buffer and spring, clean and lubed
6 Months or 5K rounds:
All the above
Give bolt and carrier good carbon scrape
Give chamber and bore good cleaning
12 months or 10K rounds:
All the above
Replace complete bolt ass’y
Replace all fire control springs
Replace buffer spring
Locktite, re-tighten all accessory bolts
Fresh batts in everything, if not replaced already
This is a general maintenance schedule that I follow, which is based on roughly 10K rounds per year. If you shoot less than that, you could adjust some accordingly, but the small parts and springs are so cheap I would stock up now and refresh annually anyways.
You may want to stock up on some tools, such as a good AR armorers wrench, a small bench vise, lower receiver block, and general hand tools: screw drivers, wrenches, pin punches, hammer/mallet, carbon scraper, etc.
Mil spec bolts are supposedly made for at least 10K rounds. You can push them out that far or swap them out sooner. For example you have 8K on one but threat levels just kicked up. Makes sense to swap out fresh one now.
Mil-spec bbls are supposedly good for 20K rounds but I suspect you’re gonna see some groups open up before that. I would strive for 2.0 MOA accuracy, which puts us at 8″ at 400m.
I would try and keep some known mil-spec parts available to compare and measure off of. Things like buffer spring length become obvious, but also things like wear on fire control or bolt parts. Until someone comes out with a good set of drawings, direct measurement of known parts is the only way to be sure.
At any rate, 10K seems to be the magic number here. You could probably push past that, but staying under that will probably keep you from catastrophic failure (as long as parts are mil-spec).
If you are not capable of performing this stuff, find a competent armorer (gunsmith) who is.
On ammo, my goal would be to have ten cans, or 8,400 rds, stripper-clipped and bandoliered.
Very few people actually do this. You will be way ahead of the curve if you do.
January 3, 2020 at 11:41 pm #135117wheelseeParticipant
January 4, 2020 at 12:10 am #135124Joe (G.W.N.S.)Moderator
On ammo, my goal would be to have ten cans, or 8,400 rds, stripper-clipped and bandoliered.
From the Thread Ammunition Stockpiles for Contingencies.
I advise people to decide on a dedicated number of rounds per firearm (not caliber). Then determine a percentage of rounds that will not be used (war reserve). As you get to halfway point between dedicated number and war reserve start looking for deals to replenish (always on the lookout for great deals).
You have two rifles and two pistols in your household.
Dedicated rifle number 10,000 rounds.
Dedicated pistol number 5,000 rounds.
So you need 20,000 (10,000 war reserve) rifle rounds and 10,000 (5,000 war reserve) pistol rounds.
So when your stocks get down to 15,000 rifle and 7,500 pistol start looking for ammo, but never dip into war reserve for any reason other than SHTF.
Okay the last thing I want is for people to advertise their stocks of ammo.
The question of how much ammo to stock as well as carry is certainly debatable, the main point of this Thread is to encourage a realistic assessment of your needs.
I’ll start off with our possible 16 man Citizen Unconventional Tactical Team (CUTT).
We’ll start small, a light to moderate day of battle could see the use of 200 rounds each. That’s 3,200 rounds used by CUTT.
OK, 38,400 rounds seems like a lot of ammo, but using above numbers it’s only 12 days of fighting for this CUTT. Of course your not going to be fighting 12 days straight (I hope), but at only 1 fight a month you only have years worth of ammo. How long are your guestimated scenarios lasting?
So am I saying you need a 38,400 rounds of ammo?
What I am saying is have you realistically assessed your requirements?
So you don’t have a CUTT?
A smaller let’s say 4 man team may use 300 rounds or more if hit by a larger group. That’s 1,200 rounds.
OK, 10,000 rounds of ammo again can seem like a lot, but even this is just 8 days of fighting!
On the Blog, the Article “Some questions answered (1): Ammo & Rates of Fire” has gotten some comments suggesting a rough amount of ammo to carry as much as 500 rounds.
I don’t think this a too unrealistic number with no supporting arms available for small say 4 man team carrying heavy. I think a CUTT may carry less depending on conditions, however 300 rounds would be around the bottom limit in my opinion.
So something to think about.
January 4, 2020 at 10:32 am #135183
Funny I read the Recoil article on building a 250 dollar AR, and while it was entertaining, I think it reinforces what the 1st Sgt has said all along about buying known quality, brand name, mil-spec rifles. That POS shit choked in all the usual ways, due to piss-poor quality parts, including springs, which are a lot more important than people think. I would go as far to say that they should be considered expendables and swapped out on a regular basis. At any rate, it establishes a lower limit for a build, which is probably in the neighborhood of 600 bucks or thereabouts. And even then you’re gonna be putting a lot of gun-smithing into it, so if you have to pay for that labor, yeah, better off just buying a good factory rifle.
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