ACR and 5.56 ammo

[mikethebike]

New thread because the old thread went full retard.

So I posted this question on the ACR sticky, but Im thinking maybe its not very visible.
Anyway here goes, my new to me ACR runs well with all my mags and all types of 223 ammo, even when running it really fast i.e. aa beowulf magdump.

My problem happens when Im running 5.56 xm855, I get stovepipes and a jam after 2 or 3 rounds. Im thinking the bolt is running to fast for it to clear the spent casing out before loading a new round, from what I could tell when clearing the problem.

Some of the guys on the acrforum were saying that when they swapped their s/u regulator to the new h/l regulator and running 556 on the h setting this cleared the issue.

I was wondering if any of you had ever experienced this problem running your acr on 556 with a s/u regulator, and if it is even possible to get a h/l regulator here in Canada?

Heres a free cute pic of the rifle.

 

[Suputin]

The obvious solution is to run 223 ammo in your rifle. Why screw with something that works?

 

[mikethebike]

The obvious solution is to run 223 ammo in your rifle. Why screw with something that works?

obviously yes, i could just run 223 and be happy.

Trying to figure out why 556 is having cycling issues though as Id like to learn a bit on this platform and its limitations.

 

[b_w.]

I have run some hornady 556 tap and never had problems...not doing mag dumps though

 

[mikethebike]

I have run some hornady 556 tap and never had problems...not doing mag dumps though

Come to think of it, I did shoot a full 15 rounds of xm855 very slowly as my first mag of the day and it didnt jam. hummm only started to jam about after 30 rounds of xm855, i then switched to regular ae 55 grain and it ran fine for the rest of the day on that 55 grain ae ammo, shooting fast too.

this is a bit weird.

 

[drifter dave]

Still in break-in phase, would be interesting to see if this clears up after a few hundred more rounds. Or maybe it just doesn't like the hotter ammo, sounds like you're not the first to see that behavior.

 

[mikethebike]

Still in break-in phase, would be interesting to see if this clears up after a few hundred more rounds. Or maybe it just doesn't like the hotter ammo, sounds like you're not the first to see that behavior.

Yah thats what I thought, really soft shooter though, whoa, I love it, even my wife thought it was a really nice shooter. Her first words were, whoa this is a nice rifle! Which is a problem...

 

[NoTarget]

Yah thats what I thought, really soft shooter though, whoa, I love it, even my wife thought it was a really nice shooter. Her first words were, whoa this is a nice rifle! Which is a problem...

If she's ok with you buying these rifles it's not really a big problem, is it?

 

[mikethebike]

If she's ok with you buying these rifles it's not really a big problem, is it?

its a problem when it becomes "her rifle", too many rifles have gone down that road...

 

[NoTarget]

its a problem when it becomes "her rifle", too many rifles have gone down that road...

That's a problem I'd like to have. My wife tolerates my rifles and a $3000 purchase is out of the question.

 

[drifter dave]

Not again..

Yah thats what I thought, really soft shooter though, whoa, I love it, even my wife thought it was a really nice shooter. Her first words were, whoa this is a nice rifle! Which is a problem...

 

[Ix]

You mean you are having problem just with the 62gr 5.56 load? Cause I didn't try that in mine, but it never had any problem with the 55gr 5.56 Norinco (other than what I mentioned in the ACR thread, which seems to be mag related).

 

[mikethebike]

I just tried the 62 grain 5.56 xm855, not the 55 grain, just my preference but I dont touch Norinco.

 

[cr5]

If you can find a source for the optional regulator let me know as I would buy one even though my rifle cycles fine with the standard one. My second barrel and gas system is only missing the regulator so I'd like to get another one.

edit, I just emailed Gravel agency and also Bushmaster about sourcing the optional regulator, I'll post any info I get from them in the ACR sticky thread.

 

[mikethebike]

If you can find a source for the optional regulator let me know as I would buy one even though my rifle cycles fine with the standard one. My second barrel and gas system is only missing the regulator so I'd like to get another one.

edit, I just emailed Gravel agency and also Bushmaster about sourcing the optional regulator, I'll post any info I get from them in the ACR sticky thread.

Thanks, I'd sure be interested in getting one of those H/L ones, its not like we are going to ever use the S setting.

 

[redshooter]

I just checked the COL of some AE 55 gr stuff I have in LC brass...so much for Federal quality...2.90"+. Worse still my excitement at getting LC brass was killed by it all being under spec, 2.40"-2.48". I just looked at a few sites stateside and one guy stated that the stuff offered on the civilian market was rejected by the military. According to my feeler gauge there's nothing wrong with my caliper.

Also why do all you gas gun shooters claim 5.56 is hotter...it's like flower power compared to my great hairy 75 gr HPBT loads. On that note I'd really appreciate a PM if anyone knows where I can get some once fired LC brass that I can trim to a uniform 2.50"-2.55".