When we discuss the durability of guns, we generally prefer to look to folks who put statistically significant volumes of ammunition through those guns. Jeff, as a range owner, has guns that over the course of a couple years, might rack up 100,000 rounds or more. Jason, an agency armorer, is responsible for hundreds of guns that each, will burn through several thousand rounds in a year in the hands of his agency’s police officers. And as a competitive shooter and instructor, I have found myself burning through well over 25,000 rounds of ammunition even in “slow” years where I haven’t had time to compete. Still, all of this pales in comparison to facilities like Battlefield Las Vegas, one the largest commercial ranges in the country. These guys will burn through 400,000 rounds in a single month and Ron Henderson, of Battlefield Las Vegas made a great post on his firm’s experience operating AR15s in a high volume environment. He leads off with some interesting facts about their experience with the AR15 and what breaks.
– 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. It’s an easy fix with tig welding but they crack. We have yet to lose an upper or lower receiver from cracking.
– We get about 20,000 rounds out of bolts before we start experiencing issues. The headspace gauge will start getting 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.
– 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 flash hider as compared to muzzle brakes on an AK-47. The muzzle brakes will literally split in half, looking a like bird with his beak open and go flying down range.
There are not a lot of shooters outside the military, law enforcement, or the competition world who will put enough ammunition through their guns to discover issues like this. Even in the competitive shooting world, it will typically take a single high-volume shooter well over a year to gather this much information about a single rifle. Understand that when you tell us you’ve put 2,500 rounds through one gun you’ve owned for ten years, we are comparing that data point with people who will put 2,500 rounds through one gun in month or, in the case of Battlefield Las Vegas, a single day.
Henderson also had some very interesting comments on piston-driven AR15s. Personally, I have not jumped onto the piston bandwagon where the AR15 is concerned. Mainly because so many retrofits seemed just plain flimsy when compared to other 5.56mm rifles that were designed from the ground up as long or short-stroke, piston-driven guns such as the FN SCAR, Sig 550, or even the old AR-180. My opinion aside, it seems this range has found that only on piston AR15 upper works in their environment…
– 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”.
– The only piston system to last on the range so far is the HK416 and TD415 system. Ever other systems we have tried has failed in one way or another. I won’t say who’s broke or how they broke so PLEASE don’t ask. Each mfg has their own system for cleaning intervals and we may not follow their way. We have a way of cleaning and keeping records that suits our needs because of so much use.
Another really interesting tid-bit that has long been a subject of discussion is the longevity of magazines. Henderson says USGI magazines have outlasted ALL other magazines. This includes all generations of P-MAGS.
– USGI mags have outlasted all of the other brands. We use UGSI (Brownell’s with tan follower) and on a mag for mag basis, they have outlasted Pmags and a few of the other mags that we get from mfg’ers with new weapons. We don’t have to worry about various generations with different weapons like the MR556, SCAR, F2000, Tavor or a couple of others that use AR15/M4 magazines.
You can read the original post over at AR15.com. Some of the comments are at least entertaining. But further down, there’s another really important take away regarding your favorite brand of lube. Specifically, Henderson says, “All of the lubes we have ever used worked as long as we continued to lube the weapons. Some lubes lasted longer than others but again… they ALL worked as advertised.” I honestly can’t disagree with him but, keep in mind, this is under range conditions. Our own experience at GOTR is that some of the bio-degradable, food or plant based lubricants out there seem to present issues in freezing temperatures. That said, WE do not have enough data on this to tell you definitively that the failures we have seen were directly attributable to the lubricants themselves or, as the manufacturers suggested, excessive/improper application of the product. Again, the original post and thread are worth a read and can be found here.