CFE 223/AEM 5 dirty

[greg1147]

I was doing some load testing for the latest and decided to finish off the CFE 223 62 gr FMJ then some 77 gr TAC and last AAC 77gr out to 500 yds
Running suppressed on a 18" Douglas barrel MK 12. The las two round failed to fire cleared each. No primer strike, pulled the BCG and found the firing to good just not making contact with the primer. Lot of carbon build up. Did some field cleaning and ran OK but the BCG is filthy. Question, is CFE really that dirty or just me running to much ammo through the rifle in a short period of time. No mag dumps or excessive rounds down range. Or maybe the nature of the AEM 5. Would it help to run the BCG dry? Pic of the BCG later.
being a really dirty suppressor. TIA

 

[simonp]

You asked if it was you running too much ammo but I don’t see that you mentioned how many rounds you’d shot prior to the issues. Was everything clean at the start?

 

[FatBoy]

I ran a test, firing 50-100 rounds per session over six months for a total of 750-800 rounds without cleaning, just a few drops of oil onto the carrier through the ejection port. 100% if the shots suppressed. Zero failures to function. I finally just got bored and cleaned it. It was filthy, but working like a champ.

77gr SMks. RL15. Mixed primers. Mixed brass, some new some several times resized.

Mod0 build with rifle gas, Carbine buffer buffer system.

 

[Wile_Coyote]

I've only shot CFE223 in my Grendel, but found it to be really dirty.

 

[greg1147]

You asked if it was you running too much ammo but I don’t see that you mentioned how many rounds you’d shot prior to the issues. Was everything clean at the start?

About 20 rounds of 62 gr reloads with CFE 223, and clean from previous range day
Just finished cleaning it, going out again tomorrow and do it again, I don't have any more CFE so its TAC and Winchester white box 62 gr
and maybe AAC or IMI.

 

[FatBoy]

About 20 rounds of 62 gr reloads with CFE 223, and clean from previous range day
Just finished cleaning it, going out again tomorrow and do it again, I don't have any more CFE so its TAC and Winchester white box 62 gr
and maybe AAC or IMI.

I roll my own most of the time but the AAC 77gr has caught my attention. Curious what your take is. Accuracy. Reliability. Repeatability. I don’t think I can reload for $.50 a round anymore and RL15 is unobtainable. Certainly can’t do it for less if I include the hours I spend doing 1000 rounds.


Also curious what the internals look like after shooting 50-100. AEM5 is always going to have a lot of gassing, but the residue to rl15 is light. Not sure what they use for powder.

 

[FatBoy]

Stupid question, but your carrier is chrome lined, right?

 

[B y r o n]

I think that whatever powder you choose to run is going to be dirtier as soon as you add a suppressor.

 

[DownhillFromHere]

is CFE really that dirty

Yes. In 50+ years of reloading, the only other powder that even comes close to leaving as much black crud in barrels is Alliant Unique which, of course, is an ancient pistol/shotgun powder.

I use it primarily for loading 75-80gr ammo for my bolt-action .223s because I got a bunch of it cheap. I don't mess with gas guns much at all anymore, but it does indeed make a mess in my AR. I can only imagine how nasty it must be in a suppressed gas gun.

 

[greg1147]

Stupid question, but your carrier is chrome lined, right?

Yep

 

[winniedonkey]

I was doing some QL what ifs on CFE223 the other day and noticed the powder burn % for my uses of 16" barrels for 223/308 was low 90s. Longer barrels had more power burn. I was looking for a ball park before I test some loads this summer in the Florida heat.

 

[Wile_Coyote]

CFE223 with a can is really dirty. It leave black residue all over everything. Nitride BCG makes cleanup easier but still grungy.