Thread: .17 HMR blow up

Originally Posted by Sharki

Better than blood or aqueous humour ( eye fluid)

spontaneous incontinence ??

Might be the best pest control round ever invented - there are other ways to kill pests that don't carry such a high level of risk IMO. Having seen the aftereffects of one of these .17 rimfire clustrflucks I'm not going to be the one right by the thing when the loud button gets pressed. I don't even like being behind them on the range...

I had a bolt action here that did the same a while back (I think it was a Savage - though not important), it blew the mag out, damaged the stock and bent the surrounding steel plate. I checked out extensively, headspace etc. and the gun was in perfect condition, ended up it was the ammo. To get a failure like that, it generally has to be around the head of the case, where it is not supported in the chamber, the gas has to go somewhere and that is where it goes.

Subsequent reading it seems that there was a batch of ammo that was suspect and lead to these failures.

Yer we are all good, a bit of poo definitely came out.

I had a Bergara to fix that did a similar thing, blew the mag up & the extractor off, can't recall the ammo but it had blown out just by the head/rim

Put everything back together & it was as good as gold

Got some Browning ammo to test with & nearly every single bloody one split at the neck shoulder junction, FFS

CCI was all good

Interesting thread. I shot hornday ammo is my fathers cheap stirling, neck splits are very common.

Yes, the packet looks old and is faded.
Most times we eject the case never to be seen again and night shooting more so.
I've started to try and keep as many cases in a night to inspect later, just out of interest and batch number.
KH

The stranger danger of old ammo and humidity.
My failure was what I'd call catastrophic, although the strength of the T Bolt held, the stock and mag and extractors didn't. Plus some minor things like the projectile stuck half way down the barrel.
I took a metal detector back the next day to find the mag and case.
Pictures are poor! Yet enough for education purposes.
And you are right about the sound! It's intense to say the least, especially when you've snuck up on a rabbit! Then they say thunder only happens when it's raining, I would differ on that one.
KH

Total case failure? Was the barrel blocked at the end of the episode or evidence of obstructed barrel or just a case failure you think? Nasty either way.

Totally case failure No.3 and as said the projectile only made it halfway down the barrel. I had just shot a rabbit and moved up on the next to get a good shot at it. So there was no possibility of obstruction.
It came from a batch I brought in the shortage.
It's is a learning experience, with no damage to me. Tentman+ thought I needed to make a contribution to the forum! Hence the post. Saying all that, firearms are built with case rupture in mind, to bleed off the gas as best as possible, which I think you are well aware of.
The hardest thing in all of this was! I didn't like being without the rifle for a few weeks.
KH

Yeesh, I would seriously consider sending a batch of that brass including the failed case away to go back to the manufacturer for analysis - unless we are talking the shortage of the early 1940's or the early 1970's I would not be considering age of the ammo to be a factor in the failure as per the photo you posted. Dodgy .303Brit from Pakistan or the last of the Greek HXP from the bottom of the drums that looks like it's been recovered of an ancient Persian shipwreck yep no issues with that if you decide to shoot it and it blows up but recent manufacture in the last 5-8 years bugger me - that's not cool at all.

Especially given that the .17HMR didn't really get underway in NZ until 2004 to 2005, after the hype of it's release in the US in 2002 and 2003... I remember the first semi auto's that came out in .17 and the drama's that came with those splitting cases in half, blowing necks apart and occasionally disassembling themselves spontaneously. This has shades of that all over it - but as you say bloody lucky to have happened in a bolt gun with the breech still closed and locked!

Swop --- 17 hmr CZ barrel plus ammo, for equivalent 22 mag barrel

Originally Posted by flock

Swop --- 17 hmr CZ barrel plus ammo, for equivalent 22 mag barrel

You've got to be kidding.
KH

Originally Posted by flock

Swop --- 17 hmr CZ barrel plus ammo, for equivalent 22 mag barrel

You've got to be kidding.
KH