As an AR-15.com member, I am often looking for interesting posts to share. Sometimes they contain incredibly useful information and other times .. not so much. This forum post on the heavy use of AR-15 and AK-47 rifles really got my attention because it re-affirms what I have been telling customers for years: while the AR is a princess and likes to be clean .. don’t discount her on the reliability side.
The forum post author is involved with a range in Nevada that offers their clientele access to full-auto rifles. Full-auto is the most-abusive form of torture for a rifle and here’s how the AR did against the legendary AK:
– Some of our M4’s have well over 200,000 rounds down range. Barrels have been replaced, gas tubes have been replaced, BCG’s have been replaced but what sets it apart from the AK47’s is that upper and lower receivers continue to function. AK’s get to about the 100,000+ round count and rails on the receiver will start to crack.
The weakest link in any machine will be the one to fail. What any engineer tries to do is make sure that the easiest, lowest cost part is the one to fail. The receiver .. is not that part. ~100k rounds and you’re receiver will need an experienced welder to mend it or it will have to be replaced. As the ATF defines it, the lower receiver is the firearm – you could be looking at buying a new “gun.”
We get about 20,000 rounds out of [AK] bolts before we start experiencing issues. The headspace gauge will start getting [SIC] closing on NO-GO but not close on field. We will lose a lug on the bolt. The bolt will start skipping over rounds in the magazine and fail to insert a round. We use LMT and Daniel Defense bolts and some will actually go longer but at about 20,000 rounds is when we will start to see issues appear.
20,000 rounds on an AK bolt and it’s toast, but what about the M4/AR-15?
– Gas tubes will erode away at the FSB after 12+ months
– Charging handles will “stretch” allowing the locking lever and spring to fly out
– Hammer pins and disconnectors on the 8.5″ full-auto’s will break after approximately 4,000-5,000 rounds regardless of the buffer weight
– We have yet to lose a single [ar-15] flash hider as compared to muzzle brakes on an AK-47. The [AK] muzzle brakes will literally split in half, looking a like bird with his beak open and go flying down range.
This is how an inexpensive, easy to replace item fails to preserve the more difficult or expensive parts of the machine. Your car sacrifices oil filters, belts, hoses and timing belts/chains to keep you from replacing much more expensive components .. like the whole engine.
Next up is the whole piston vs. direct impingement thing .. there isn’t a single paper-shooter in the world that needs a piston-drive, but more power to you if you’re willing to spend an extra $300+ to make your BCG a little easier to clean vs. investing in other upgrades. I’d be thrilled to convert your rifle at your cost if you choose to go this way 😉 although it would be against the advice I’d give you if asked.
We no longer use ANY piston conversions or factory pistons guns with the exception of the HK-416 “knock-off” TDI upper. I purchased a FACTORY brand-new MR556 and it started keyholing after only 10,000 rounds. I was SO pissed because I spent all that money on the gun and it couldn’t last 10,000 rounds. I had barrels from before we even opened the range with 1,000’s of rounds on them from J&T Distributing (chrome-lined) that didn’t keyhole well into the 80,000-100,000 range. I don’t know who makes or made the J&T barrels but I was so pissed that actually wasted the money on a MR556 and that’s all I got from it. I purchased two of the 14.5″ TDI knock-offs approximately 6-8 weeks ago and they have been on the line daily with ZERO issues. I only purchased them because people will come in specifically request the “416” and even they’ve never handled a weapon their entire lives, they KNOW that the top half isn’t the “416 like in COD/MW”.
He certainly wasn’t explicit in calling out piston vs. DI, but the point was made. The piston system did not prevent adverse wear on any component in the gun and, in fact, may have made things worse. As a business manager or owner, he found the return-on-investment to be poor. The AR-15 was not designed as a piston, op-rod, blow-back or any other operating system. If you convert it away from direct impingement, you get the joy of being a member of a small community of barely-tested designs.
I personally own both AKM-style (Ak-47, AK-74, SKS and more) rifles as well as AR-15/10 rifles and love to shoot them all. Hopefully, this additional information has helped you decide which, if not both, platforms you’d like to own and why.