High Round Count Users

[Jaywalker]

Has anyone fired one upper and barrel to a high round count? I'm thinking 5,000 or 10,000 rounds.

If you have comments on what you've had to replace, that would be interesting,

[Mutt]

Bolt, bolt gas rings, occasionally a worn gas tube, extractor ..... I'd keep an extra bolt and all the moving parts for a bolt and BCG on hand, as well as a complete lower parts kit. That should keep you going for a long long time.

[LRRPF52]

Has anyone fired one upper and barrel to a high round count? I'm thinking 5,000 or 10,000 rounds.

If you have comments on what you've had to replace, that would be interesting,

On 5.56 guns, the maintenance schedule calls for ejector and extractor spring replacement between 2000-4000 rounds, and recoil spring replacement at 10000 rounds, or when it fails a minimum length test. Who knows what these benchmarks are for the Grendel, but I keep spares on-hand for all my blasters as a rule. I also like the grip cores of the Magpul MIAD and MOE grips, where you can keep an extra bolt, firing pin, extractor assembly, firing pin retaining pin, etc.

Some prefer to just drop in a whole new Bolt Carrier Group and recoil spring at 10k. I distribute the high volume over several carbines, so I have to pay more attention to my precision guns for round count. Either way, keep a log boo on all your rifles so you know how many miles are on the oblastmeter.

[Jaywalker]

Thanks, I'm pretty well read up on the maintenance schedule for the 5.56. I'm wondering what Grendel users have shot through their rifles, given the ammunition costs more.

So, who has shot their Grendel 5,000 or 10,000 rounds?

[Variable]

I've at least gone over 5k in my 10.5" rig. I've only had one breakage of any kind so far. That was a broken extractor (front lip snapped clean off). I think that was in my 10.5", but it could have been my 14.5"... I don't really keep any records (I know I should...), but that's all so far. I usually shoot suppressed, and my guns get pretty filthy. When you let the carbon bake in hard and then shoot full auto suppressed, it only figures you'll break something eventually. I'm too broke to go burning up cases of Wolf MPT lately though! Either way, I also keep extra bolts and pins in MIAD grips on my Grendels too. Bust something? No big deal, drop in a new one and let her eat.

[bwaites]

Jaywalker,

I put more than 6000 rounds down my 19.5 inch barrel before I sent the upper back for rebarreling. I shot lots of .25 inch 5 shot groups at 100 yards, and plenty of sub 1/2 MOA groups at 200 and beyond. Even at 600 rounds it would still shoot sub MOA with a couple loads, though it wasn't as accurate as it had once been.

I field tested for Bill Alexander, so I am harder on parts than most. I managed to break one experimental bolt in that time. I didn't break ANYTHING else. I ran factory AA, factory Black Hills (both the 123 grain SMK load of 6.5 Grendel and the 123 grain Hornady load), and lots of different hand loads, including some that were very warm.

The only thing I replaced was the experimental bolt, which broke after about 3000 rounds.

I didn't manage to break anything else.

Hope that helps!

[Jaywalker]

Thanks, all.

Bill, did you do any preventative parts replacement during th e6k rounds, like gas rings, etc.?

[bwaites]

Thanks, all.

Bill, did you do any preventative parts replacement during th e6k rounds, like gas rings, etc.?

Nope, nada, zip. I even ran a torture test that lasted months where I didn't clean it for close to 900 rounds. I ran it until it got dirty enough to cause a failure to feed.

[Mutt]

The reason for the required maintainance schedule is to hopefully replace worn or high count items "before" they break. The idea is to replace items before they reach thier maximum usage. The military tests to the point that they can predict that Part A typically breaks at 16,500 (on average). So, they require that all Part A's are change at 12,000 rounds (by the armory personell). This is to hopefully ensure that a weapon doesn't fail in the field due to worn out parts. I know .... I really over simplified this explanation, but that's basically how it goes.

Now that I am a civilian shooter, several things are different. 1. I don't turn in my rifle to the armory for maintainance. 2. I always use the same rifle and don't get issued a different rifle every time. And, 3. (which only applies to some) I am strictly semi auto and don't have the capability to shoot full auto which heats up the parts in my rifle to extremes.

By owning the rifle, I know it from top to bottom and can see the wear as time goes on and change the parts as needed. Also, I can use it till failure and then just change the part. Since the Grendel isn't my SHTF rifle, it's not as critical. If you are civilian contractor or law enforcement, then curcumstances will more than likely be different for you than they are for me.

[noone]

I only count rounds on my precision rifles, and can tell you exactly how many rounds were fired any time they went out, the date they were fired, the total, and other info. For most of my carbines, whenever I have problems, or notice things like a worn gas tube, malfunctions and so on I work on 'em and fix whatever ails them.

I think I replace a precision rifle barrel about once per year, and a semi-auto carbine barrel once per year.

[bwaites]

I only count rounds on my precision rifles, and can tell you exactly how many rounds were fired any time they went out, the date they were fired, the total, and other info. For most of my carbines, whenever I have problems, or notice things like a worn gas tube, malfunctions and so on I work on 'em and fix whatever ails them.

I think I replace a precision rifle barrel about once per year, and a semi-auto carbine barrel once per year.

WOW!! You are putting a LOT of rounds downrange! If you wear out carbine barrels that fast, you are seriously pumping them out! Precision rifles can go at anywhere from 600-900 rounds for a 6.5-284 to 3-5000 rounds for a .308, so I can see swapping those barrels more frequently.