AR Thread

[res]

Is the barrel nut done up properly?
A mate has that setup with no dramas whatsoever and I have another of his cans with no problem

[EK9132]

Is the barrel nut done up properly?
A mate has that setup with no dramas whatsoever and I have another of his cans with no problem

Barrel nut was swapped by a gunsmith so im assuming its all kosher. Will have another go this weekend if I get a chance.

Sent from my GT-I8190T using Tapatalk

[Spanners]

MPI only picks up external faults.
It will only identify a fault that would be apparent via failure in the 1st few firings.
It's great for selling things to people...
govt contract, service, sniper and tactical work too.

[gimp]

It prevents that failure in the first few firings - ie you're not buying a pre-broken gun

[redbang]

Interesting stuff. At the gunsmiths yesdy with new toy, borescoped, and found that it had been fired. Not many he thought, perhaps 10 rounds. So maybe some proof/functional testing goes on as well.

[Rushy]

Interesting stuff. At the gunsmiths yesdy with new toy, borescoped, and found that it had been fired. Not many he thought, perhaps 10 rounds. So maybe some proof/functional testing goes on as well.

Yep that is interesting. I got a new AR recently and that had obvious signs of having been fired.

[scaggly]

Yep that is interesting. I got a new AR recently and that had obvious signs of having been fired.

I was under the impression that for lots of manufacturers, each new AR is test-fired before it leaves the factory to check function, accuracy etc. I've read stories from the states (or possibly canada - definitely north america) about manufacturers including the fired brass in the box with the rifle as proof that they've test fired the rifle before sending it out.

[Rushy]

I was under the impression that for lots of manufacturers, each new AR is test-fired before it leaves the factory to check function, accuracy etc. I've read stories from the states (or possibly canada - definitely north america) about manufacturers including the fired brass in the box with the rifle as proof that they've test fired the rifle before sending it out.

I never got the brass but that was the explanation that I was given when I enquired. Plausible when you are consigning to the other side of the world.

[scaggly]

Out of curiosity (and having a relatively quiet morning ahead), I went and googled it. The best discussion I found was this one HPT and MPI: still viable and necessary or outdated bureaucracy? - Page 15

In a nutshell, some rate the processes citing mil-spec, some don't. A couple of manufacturers chip in, and their rationale is that if the bolt is manufactured using quality steel, quality manufacturing etc., then there is no benefit to MPI or HPT, and that destructive testing (HPT) only reduces the life of the bolt.

Others (but not other manufacturers that I could tell) disagree with this view, but at the end of the day some fairly big names in ARs don't think either process adds much value.

I'm now better educated than I was an hour ago, and it is pretty much settled for me that the two processes aren't needed as long as you're buying parts from a reputable manufacturer.

Of course, if you're machining your own bolt, then some testing might be in order

[Ryan]

Not an AR obviously but my AK came with a factory firing report (4 rounds IIRC). I assume that this is industry standard practice?

[FletchNZ]

Yeah my DPMS AR 308 came looking like it had been testfired. Small amount of carbon in the barrel from memory.

[Bill999]

is there anyway to remove a spear mags stock without butchering the safety detent spring?

[Bill999]

too late never mind......
FUCK.

[Rushy]

too late never mind......
FUCK.

Bugger!

[dogmatix]

Yes, but you need to do this before you install the stock!

http://sportshooter.co.nz • View topic - SpearMags Stock mod