Upper Receiver: Aero Precision
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Upper Receiver: Aero Precision
Barrel?
Nope, no barrel.
Sorry guys it was a busy afternoon, it was a completer upper from SAA
Surplus Ammo & Arms Complete 16" 1:9 M4 AR-15 Upper Receiver - 5.56 - Surplus Ammo
Yeah, I'm back to chamber spec.
I have had one Wolf brand steel case stick in my AR chamber (Stag Arms, 5.56 chamber). It easily knocked out with a light tap from a cleaning rod. I have fired well over 1000 rounds of Wolf with only this one issue. I will continue to use Wolf/Tula for practice as the cost is much less. Unless you experience more failures I would not be too concerned at this point.
Once you clean up the chamber, try some brass cased ammo to see what she does.
No need for another picture, it was gunk as I was able to scrape it off with my thumb nail. The un-fired ammo does not look that way.Quote:
Originally Posted by 40Bob
Clean the crap out of the chamber, then don't put any crap back in it. If good ammo causes a malfunction--you've got problems!
Sounds like the consensus is the ammo using brass ammo and a good cleaning should eliminate the problem. I'll let you guys know how that goes either way. My gut feeling is that it will preform fine, however I wish the rifle would be reliable with any ammo. Perhaps with a few hundred more rounds things will loosen up a bit.
First, no lacquer melts off the cases and gums up a chamber. Someone on another forum took a propane torch to a spent casing and failed to get any lacquer to "melt".
The issue with the old lacquer and newer polymer coated steel cased ammo is that they do not seal inside the chamber as does brass cased ammo. The lack of a good seal causes carbon build up in the chamber. Shoot enough and you will eventually "shrink" your chamber, which can cause the next chambered round to get stuck. This results in a failure to extract which will often result in a case as shown in the picture.
The Box O'Truth website covers this quite clearly.
I agree with some of the posts that suggest partially obturated steel cases result in excessive fouling which can lead to FTEs, especially if the gun is too dry. Jon and I were shooting my SBR and it ran acceptably on Tula when it was wet...but not dry.
IMO FTEs are caused by:
-steel casings, inflexible compared to brass cases
-the load, under-powering guns with spec ports, buffer weights, action springs
The aforementioned issues are further exacerbated by out of spec uppers, specifically oversize gas ports, underweight buffers, worn action springs, etc. Steel is less malleable (higher melt point) than brass and expands/contracts in the chamber slower than brass casings. Thus steel cases tend to be torn, rather than cleanly extracted, from the chamber. With overgassed guns, this is a serious issue as unlock/extraction occurs while the (steel) case is still partially obturated against the chamber walls.
Years ago, before the Russians changed to a different laquer, it was quite common. I've seen gun gunked up horribly by melted lacquer. Many here are too young to remember, but if you are shooting some of the older surplus stuff, its still a concern.Quote:
First, no lacquer melts off the cases and gums up a chamber.
Yea, it was that red crap.Quote:
Originally Posted by HotGuns
I have my AR set up so it will not even run wolf.....Its too low powered, makes for a single shot AR.
I have no experience with that upper, but my guess is this is an underlying issue, brought to light by the ammo used. If you have the time, I'd be curious to know gas port size. I would venture to say it's likely >.063"Quote:
Originally Posted by Chris Dawg