Any AR10 guru's in the house?

[Hogwylde]

I just picked up a NIB Armalite AR10A from my LGS. The first time I had a chance to fire it was last Friday before the weather took a dump. It pretty much short cycled thru 3 twenty round mags. Dumps the empty cases in a neat pile about 5 feet away at 4 o'clock and bolt closes on an empty chamber.

I've seen some threads on 308.com that AR10's take about 200 rounds to break in and the guys at Armalite are telling me that 147gr ball is too light to break it in with. I've picked up some heavier loads, but the weather is freaking cold and I'm not going to be able to shoot this thing for weeks.

Any advice on how I can help this thing along with the break-in? It seems to me that the recoil spring needs to "break in" because it's a little too strong for 147gr loads. I'm wondering if leaving the bolt locked back while it's in the safe will help. I scrubbed the bottom of the bolt carrier......it has some rough grease like residue on it that I though might be dragging on the rounds in the magazine. Any other advice on how to make this sucker run on 147gr ball ammo is appreciated.

 

[singlesix]

Breakin = parts not fitting right so grind them by shooting heavy loads? I picked up a DPMS AR pattern 308 and shot 147 grain bullets with no issues. My gun functioned as designed. I shot my at an indoor range due to the weather also, getting old and whimpy I guess.

 

[halfmileharry]

I've got the Armalite AR10-4 and it's ran 100% on the Lake City 149 gr from day 1.
Did you pull it down and check it out, grease the bolt rails, and oil the bolt assy heavily?

 

[Deaddogwalkin]

I have a 26" rra lar8 that doesn't really like light ball ammo, it will still cycle it but the buffer spring rattles just a little. Problem seems to be solved with fgmm175's, which easily shoot sub moa.

 

[indyjohn]

I've got the Armalite AR10-4 and it's ran 100% on the Lake City 149 gr from day 1.
Did you pull it down and check it out, grease the bolt rails, and oil the bolt assy heavily?

This is how I would expect an Armalite to behave out of the box.

There may be some degree of break in but what you describe indicates to me something is not in spec. You didn't detail what 147 gr ammo you were using.

On a semi related note, this gun is on my to buy list. Would give rep to know what it took to get it out the door.

 

[halfmileharry]

This is how I would expect an Armalite to behave out of the box.

There may be some degree of break in but what you describe indicates to me something is not in spec. You didn't detail what 147 gr ammo you were using.

On a semi related note, this gun is on my to buy list. Would give rep to know what it took to get it out the door.

I'm guessing proper lube and ammo combo issues with a tight tolerance new gun.

 

[Hogwylde]

I'm using PMC Bronze 147gr FMJBT. Armalite has this rifle listed at $999 on their website (Defensive Sporting Rifle^TM 10). Yea, I know, it says the model is DEF10, but on the side of the reciever it's stamped AR-10A and no mention of the DEF10 model number. PSS got it for me for $939. I got some ammo and spare P-Mags to go with it too. Didn't actually have to pay for it either. My father died and I traded 6 Ruger Blackhawk pistols for all this stuff.

 

[indyjohn]

Wow. Didn't see that coming. Sorry for your loss.

 

[halfmileharry]

I'm using PMC Bronze 147gr FMJBT. Armalite has this rifle listed at $999 on their website (Defensive Sporting Rifle^TM 10). Yea, I know, it says the model is DEF10, but on the side of the reciever it's stamped AR-10A and no mention of the DEF10 model number. PSS got it for me for $939. I got some ammo and spare P-Mags to go with it too. Didn't actually have to pay for it either. My father died and I traded 6 Ruger Blackhawk pistols for all this stuff.

The PMC is decent ammo and wouldn't worry about shooting it in any of my ARs.
I'd check the bolt lubrication and make sure you got all the goo out of the moving parts good.
I use Slip 2000 and RemOil. Zero failures, issues at all. Sub zero weather as well. Works pretty darn good.
Sorry about your father passing Hogwylde. Lost mine 7 years ago this coming February. Circle of Life stuff.

 

[indyjohn]

I'm using PMC Bronze 147gr FMJBT. Armalite has this rifle listed at $999 on their website (Defensive Sporting Rifle^TM 10). Yea, I know, it says the model is DEF10, but on the side of the reciever it's stamped AR-10A and no mention of the DEF10 model number. PSS got it for me for $939. I got some ammo and spare P-Mags to go with it too. Didn't actually have to pay for it either. My father died and I traded 6 Ruger Blackhawk pistols for all this stuff.

I understand you say your gun is stamped AR-10A, however the web link you reference states this: "Rifling Twist: 1:11.25" RH, 150 - 175 gr. ammo with 168 gr. being ideal"

My next step would be to determine actual rifle model and rifling twist to determine appropriate ammo to use.

 

[sloughfoot]

I have to admit to a dislike of everything made by Armalite. If you review any of my previous posts on AR type rifles of 223, 308, and other calibers, I frequently say one is as good as another. I truly believe that if you shoot your Armalite enough, it will smooth itself out and will be a very good platform. Eventually....

There is no good reason why 147 ball ammo should not function the rifle and be reasonably accurate as well. Operation does not depend on recoil developed by bullet weight.. Operation depends on gas pressure. Every appropriate .308 ammo will develop this gas pressure. Especially Mil-Surp ball ammo.

What you need to do is lube the heck out of the BCG while shooting numerous mags through it. It will smooth out and become reliable. As long as your problems are not magazine related. Only you can diagnose that issue.

A good friend, Mike Gingher, was Armalite's chief armorer. RIP Mike. Tip one for me.

But I told him of my displeasure with the general status of Armalite's rifles, even their NM AR's. I handled every one of their rifles on Commercial row at Camp Perry and never was pleased with what I had in my hands.

Indyjohn, Just purchase a DPMS GII and separate yourself from these kinds of problems. It is a VERY good .308 AR. Trust me on this. PMAGS and DPMS mags are cheap and totally reliable.

 

[sloughfoot]

I've got the Armalite AR10-4 and it's ran 100% on the Lake City 149 gr from day 1.
Did you pull it down and check it out, grease the bolt rails, and oil the bolt assy heavily?

OP this is very good advice.

 

[M67]

Indyjohn, Just purchase a DPMS GII and separate yourself from these kinds of problems. It is a VERY good .308 AR. Trust me on this. PMAGS and DPMS mags are cheap and totally reliable.

If he goes that route, doesn't he get into a whole different realm of 308 proprietarity?


For the time I had my DPMS 308 it was picky on ammo for running 100%. They had to be stout loads, and even those "blaster" loads that cycled my DPMS has a hard time cycling in my POF all of the time.

308s are just....different. Yes, those PMCs should cycle just fine, I have a friend who shoots 145gr PPU FMJ through his AR10 with great success since day 1; but maybe this particular rifle needs stouter loads with higher pressures.


As mentioned before, I'd strip it and take all the factory stuff out of it if you haven't already. Degrease it, and get some good lube in it. 30 weight EWL worked well for my DPMS.

 

[sloughfoot]

If he goes that route, doesn't he get into a whole different realm of 308 proprietarity?


For the time I had my DPMS 308 it was picky on ammo for running 100%. They had to be stout loads, and even those "blaster" loads that cycled my DPMS has a hard time cycling in my POF all of the time.

308s are just....different. Yes, those PMCs should cycle just fine, I have a friend who shoots 145gr PPU FMJ through his AR10 with great success since day 1; but maybe this particular rifle needs stouter loads with higher pressures.


As mentioned before, I'd strip it and take all the factory stuff out of it if you haven't already. Degrease it, and get some good lube in it. 30 weight EWL worked well for my DPMS.

I agree. I prefer the DPMS proprietarity though. (Did we spell that correctly?) My DPMS LR308 has been totally reliable since the first round. It is a first tier rifle for that day when I need to grab a rifle for serious work.

That is just my personal experience and personal preference.

If my son asked me what AR10 pattern to buy that is likely to be reliable from round number one, I would tell him to buy a DPMS GII.

That is my opinion.

 

[sig1473]

Big differences between a DPMS GenI LR308 and the DPMS Gen II.

 

[M67]

If my son asked me what AR10 pattern to buy that is likely to be reliable from round number one, I would tell him to buy a DPMS GII.

The Gen II looks better and is lighter, but I don't like the fact that you can't change the charging handle. Aren't the barrels proprietary to the GII? And do they use a low tang aftermarket rail or is this the 4th different rail height DPMS has used? The BCGs are completely different, etc. Not that I have that much room to talk, pretty much everything on my POF is proprietary from the piston, gas plug, barrel nut, rail, BCG, etc.

But at least with 308s there are 2 common platform for parts, Armalite style and DPMS style. The GII just makes things more difficult if you like having a supported platform.

 

[wsenefeld]

My father's DPMS pattern .308 had the same problem during break in. The bolt locked up very tight with the barrel. I bought him a YHM qd flash hider and since he's one of my trustees, I let him borrow my YHM .30 cal for a while. After 125 rounds, he tried it without the suppressor and it ran fine. The parts just need to mate up and breaking them in is the best way to do that.

 

[rvb]

My thoughts....

PMC is often relatively weak factory ammo. A good milsurp or match load etc might have the extra oomph you need to get it to lock back on an empty mag. I ususally keep a box or two of PMC on hand for things like setting adjuable gas blocks. If it locks back on that, it'll lock back on anything. otherwise it sounds like it's running ok?

Many folks dismiss the break-in, but some samples need it more than others. It's just a matter of those raceways on the carrier getting smoothed out and helping it cycle smoothly. Often a couple hundred rounds is all it needs.

It's cold. What kind of lube are you using? Many lubes (incl some of the more in-vogue stuff) don't do well in cold. Lube the hell out of it with something that doesn't thicken up in this cold stuff. This includes any lube you or the factory may have put on the buffer/spring. You mentioned cleaning off some factory lube/grease... I'd get some electrical contact cleaner or brake cleaner and completely degrease the bolt/carrier/buffer/spring/receiver/RE and lube with something good. Personally, I only use grease on the trigger group (and maybe a little on the buffer spring to quiet it down), oil everywhere else (I use Mobile 1 synth). When it's below freezing, many popular greases turn to sludge.

If the problem still persists, you could try a lighter buffer. I'd do this before a lighter spring.

-rvb

 

[Hogwylde]

A lighter buffer. Hadn't though of that. The one that's in it now has H3 stamped on it. I bet I can mix and match some weights and lighten it up a few ounces.

Strange that there is a website called heavy buffers that claims they can improve function by going heavier...... (Slash's Heavy Buffers | Home). I've seen stuff elsewhere that claims that AR10 are always over gassed anyway and the heavy buffers are the way to go. That doesn't seem to be the case in my situation.

 

[sig1473]

Not one single problem with my LMT with any ammo(NATO surplus, UMC, POF, Fed Goldmatch). I didn't encounter any problems with my DPMS LR308 as well, but the only thing DPMS on it were the BCG, upper & lower.