The Lucky Gunner test is a poor predictor of the long-term durability of any barrel. It was a destructive test by its very nature. The Gator Hide gas checkering of the bore surface and the throat temps they were getting when they were measuring 700+ degrees on the outside of the barrel were likely plenty hot enough to cause greatly accelerated throat erosion, flame cutting and plastic softening of the steel.
It is not remotely representative of a normal or near-normal use pattern and not comparable for those purposes.
FWIW to the subject of barrel life I probably have close to 10k rounds through my SAR-1 that I bought back in 99’ when 7.62 was $60 a case and the bore and chrome is still bright and shiny. I never did a many mag dumps and 99% of those 10K rounds were pretty slow aimed fire.
I guess my point is if its a quality barrel and you don’t shoot like John Rambo and John Matrix combined, the barrel will last a long damn time.
I think this pretty well sums up this entire discussion. If none of us can shoot enough ammo through one to tell, does it really matter? I’m thinking it doesn’t.
When steel gets soft, it has more trouble swaging a steel projectile. The projectile deforms the barrel back.
Of course, it you don’t cook the shit out of it, it is going to have far less problems.
Some people think the moral is to not use steel. I am cool with that as there is more left for me to use, I just rock on, save money and don’t cook my barrels. Please don’t buy Russian ammo, EVER!
Did you see the m193 barrel ? it was chewed to shit too… I wouldn’t call that kind of damage GTG. Just because it wasn’t shooting keyholes yet dosent mean the barrel wasn’t already nearly shot.
It would be far better to preach that if you’re going to be buying Russian ammo, be prepared for reduced barrel life. Hell, at about $380 for 2K 5.45, I can buy a barrel every two cases and still be behind the dollar curve.
I am sure used in a semi-normal fashion, you will see a minor reduction in bore life but nothing approaching what the lucky gunner destructive testing revealed.
My belief is if you repeated the test with a more normal firing schedule, you would fine something like a 15 to 20 percent difference in lifespan, not 40 to 60.
Look up a process called autofrettage, the military has been doing in for decades when it made cannon tube because it yielding stronger, longer lasting barrels.
Autofrettage is similar to what is done when a CHF and it produces a longer lasting tube.
I recently replaced a barrel of one of my 6920s that had 20K+ rounds (used in many carbine courses), with Russian Wolf, Brown Bear, and Golden Tiger (the last two being lacquered coated) shot almost exclusively through it, not because of barrel wear, but for preventive maintenance. I bet I could have gone another 10K rounds fired. I’ve probably shot 60K+ of Wolf alone to date over 5 carbines. I was still getting 3 MOA shot groups at 100 yards using IMI M193 prior to the swap. You see slewed test like Lucky Gunner’s, that shot the weapons doing mag dump after mag dump until the ammo was shot up, with extremely subjective conclusions. They should have used beer cans and dirt clods as targets since it was such a ‘bubba’ contrived experiment. The fact is, no one shoots a weapon like that, not even those of us that attend several carbine courses a year. I’ll say it again as I’ve said many times, it’s a AR, not a belt fed.
The results had more to do with a sustained high rate of fire than ammo selection, although steel cased ammo does have a peripheral effect, but not to that extent that any member here should ever have to worry about. To top it off, the weapons used were bushmasters for Christ’s sakes! Those pooping the ammo, are regurgitating hearsay, as I have not detected any noticeable accelerated wear or abnormal operating characteristics in any of my carbines that I haven’t experienced with brass ammo, which is very little. The test was completely pointless in my opinion and duped the shooting community with erroneous information. If they would have used a military grade weapon shooting 10K rounds of Wolf over a one year period, as a typical member here would shoot, they would not have gotten those results. As always, it’s your money and personal preference. YMMV and all that shit…
Or still can sling bullets at 25-50m and hit close to POA? ala a useless IMO filthy 14 discussion.
Precision groups, still stabilizing, with (insert here your favorite) projectile at 300m (my metric)
With roughly the same firing schedule, in a training environment, 10" barrels, a MK18 barrel will do 7-10K and a HK416 10-12k before performance noticeably degrades.
Barrel temps, max and sustained, velocity and projectiles used clearly matter…
I haven’t looked for or at any IAR data, but the HK M27 has a substantial barrel profile, a defacto massive heat sink with it’s large barrel nut and long heavy aluminum rail. Test data showing exact firing schedule/ammo, and barrel temps would be useful.
I don’t have any hard numbers but I was talking to a guy who has an M16 lower and he says there is a substantially noticeable difference in longevity between standard chrome lined barrel and CHF barrels.
I’d be more interested in bore diameter consistency than life. My guess is that a CHF barrel would be less prone to the bore diameter variances that button rifled barrels can suffer. But I’m not knowledgeable enough about the process to say this is true.
FYI: I’m selecting a barrel for an integral upper. That means barrel swaps will have to be done by the manufacturer. The upper will also be registered via the ATF. For a normal upper wear and tear may not be a big deal, but in the regulated world of NFA it becomes a bigger consideration.