Considering a .308 build


#1

I have no experience with building an AR, much less an AR in.308. I had a thought to acquire all these top-notch parts and with the guidance of a gunsmith have it assembled. I was thinking of Krieger barrels, matched set of upper and lower, yada yada…
Then it occurred to me, wait…so many manufactures have engendered a .308 and failed to produce a great product. Some have succeeded but many have failed to produce a dependable .308.
So what makes me think that I have any answers they don’t? I’m sure they know far more about engineering a rifle than I do. What if I end up with an expensive piece of crap? Maybe I’m just better off buying a good one from a quality manufacturer with a warranty.
Anyone have any thoughts on this?


#2

I think it would be up to the armorer to make it dependable.


#3

It boils down to what you mean by “dependable”. Any AR-10 manufactured by a reputable company should be just as dependable as it’s .223/5.56 counterpart. What separates the 2 is the issue of inherent accuracy. Generally, AR-15’s are compared to other medium power semi autos while AR-10 invariably get compared to precision bolt guns in that department.

I’ve never seen a reliability issue with an AR-10 platform built by a company that builds reliable AR-15’s, as long as quality ammo and magazines are used. It’s usually simply a matter of “you get what you pay for”. The real issues occur when the owner tries to eek a little more accuracy out of the rifle by changing things like buffers and triggers that are different than the OEM components. For example, the rifle worked fine with surplus ammo and then developed “light strikes” after a trigger job or the shooter tries running hard primers through a gun with a factory “match” trigger to the same effect.


#4

With the AR platform only three pieces really matter it terms of accuracy, the rest is just fluff. The barrel, bolt, and trigger are all you really need to worry about. Krieger makes amazing barrels, I own one myself.

As far as reliability matters, as long as your lower is machined well (not a low priced POS) your mag will sit correctly for feeding. Add an adjustable gas block and your off and running.

Also, why an AR in 308? What’s your goals for this rifle? What do you plan to use it for? If your strictly thinking of accuracy a bolt action will make your money go further.


#5

Thank you for the reply.i like the. 308 for a number of reasons. I know there are other rounds that shoot faster, flatter and hit harder. I guess part of the reason is because I have so much .308 ammo stored up already. Another factor for me is the fact that this round is fairly ubiquitous, like .223. It has a very long track record and should meet my needs pretty well since I am not an experienced rifle shot, at least not yet.
I have given thought to the 6.8 SPC cartridge. I have heard very good reports about this round. It doesn’t hurt that the Army marksmanship team had a hand in its development. I have also lusted after the LWRC Six 8. Anyway, I don’t see that round being as abundant or price friendly anytime soon. Same for the 6.5. Not to say they are not fantastic rounds with wonderful ballistics, but at least at this point I think I’ll stick with the. 308. Simplicity for me for now.
I have no illusions about the superior accuracy of the bolt platform. I think, however the rapidity with which one can reengage after the initial shot, or rapidly acquire a new target compelled me.
If I am to be totally honest I have to say that no small part of my desire for a semiauto is the inherent “cool factor” in the AR10 platform. Wouldn’t be the first time my ego pulled me toward a decision. Doesn’t sound real sophisticated but there it is nonetheless.
Perhaps as I gain more experience I will be able to branch out in my thinking a little more freely.


#6

[quote=“Gratefulpatriot, post:5, topic:1528”]I guess part of the reason is because I have so much .308 ammo stored up already[/quote] Surplus .308? Hunting rounds? Match ammo?.. Like I said earlier, this could be a “reliability” concern. A match grade trigger MIGHT not have the power to ignite hard surplus primers, and a Mil-spec trigger MIGHT pierce/damage soft hunting/match primers. This could result in FTF(too hard of a primer) or unseated primers(too hard of a strike) getting in the works of the gun. I’m not saying this is common but MIGHT happen.

As Norcal-In-AZ said, reliability is largely a matter of component fit. This could come from buying quality matched parts, or paying a skilled armorer to assemble them. As I said earlier, you get what you pay for.


#7

Well I have mucho boxes of Hornady TAP that I have had for years. It’s all stored well in ammo cans on an air conditioned space. It should be good ammo. I also have a considerable amount of Black Hills. I’m not too worried about the ammo.

A few years ago I purchased two AR10s from Armalite. I was so excited about getting them out to the range! Turns out that after 6 rounds or so the barrels swelled from the heat and the ammo would not feed. I had a very good gunsmith look at it and he was confounded. I called Armalite and they asked me about the ammo etc. and asked me to send them back.

I had some major issues come up so I was not able to follow up just got rid of the rifles. What was obvious to me was that Armalite, for whatever reason, was using crap barrels at the time.


#8

My brother shoots 6.8SPC and does very well with it. But he’s also running a 24” bull barrel, handloads with high end bullets, and lots of careful development. It’s a capible round, it’s just not something you can pick up off the self as a match round.

If your want is for a semi auto, then go with a semi auto. It doesn’t sound like you want it for anything other than the fun factor. If your goal was shooting tiny groups at some distance, then I’d say a bolt would be better.

As far as going factory vs build, I personally won’t buy a factory rifle ever again. By time I spend the money on the gun, then I add this or that to it to make it like I want, I’ve spent as much if not more than a custom would have cost me. I stand by my original post, buy a quality matched set of receivers, a good trigger, match barrel and bolt, and your good to go. Everything else is just fluff.


#9

Norcal I hear you bro. Recommendations on top quality parts?


#10

^ This. I thankfully decided to not just buy a S&W M&P 15 for this very reason. I was going to change to Magpul furniture all around on the lease expensive factory M&P 15 (~$700) and before I even added anything else I was already looking at close to $900. I was able to build almost exactly what I wanted on one of my two possible configurations I was considering for just a touch under $720. And it would run circles around that M&P.

Since this was my first AR I asked people that I trusted and got a few good brands to go with. The problem today is EVERYONE is building ARs and parts are very scarce. Magpul for furniture/grips, Aero Precision, Spike’s Tactical, and Bravo Company for most of the rest is what the consensus was with my people and some of the internets. Really it comes down to getting the most for your $$$ but not cheaping out on parts because most times you get what you pay for–or at least so I’ve been told.


#11

I hear you bro. Yeah it’s payday for all the AR parts manufacturers as well as complete rifles. I got a couple of S&W M&P 15s for my two boys and a DDM4V7 for myself. I’m actually very impressed with the S&W ARs, and the DD blew me away at the range today! My boys got red dots on their rifles and were having a ball.
Anyway I decided to go with a DDM5V2 for my .308 and then start a build with quality parts. Any opinions on the “Zero Fail” BCG?


#12

Fail Zero should be fine. I haven’t ran one, but they’ve a good rep too.


#13

Some of the mayched upper and lowers are running around $600. So if I get that, the Fail Zero BCM ETC, AND A Krieger barrel I should be okay right. Should the barrel be steel or stainless steel? Does it make a difference?


#14

Yes the type of metal makes a difference. I doubt however that you’ll be able to shoot the difference. Bench rest guys shooting tiny one hols groups, they won’t run anything but stainless. But if your wanting to do mag dumps and just shoot 2-3 MOA plates all day, you’ll never see the difference. That said, I would go stainless steel.

Yeah your sitting right at $600 for this set https://aeroprecisionusa.com/m5e1-defected-tungsten-builder-set.html
But that includes your barrel nut and the upper is complete short of a BCG. So a barrel, lower parts kit, buffer, stock, and grip is all you need.