.17 HMR blow up

So I was out 2 nights ago, spotlighting. I took aim at a hare, pulled the trigger and boom! The brother inlaw fell off the bike. I felt impact on
My fore arm then on the side of my face. Both of us felt deff. Put the head light on and the sides of the 10 shot polymer magazine had blown off, there was a black mark on the wooden stock underneath the pressure release hole. Carefully opened the bolt. When I removed the suppressor there was the projectile sat in the end of the barrel. A big shock after putting 100s of rounds through the CZ never missing a beat!

Bolt gun or semi auto

Bolt will add pics soon.

Older Hornady ammo?

Yes I think that was the problem as have read about the issues

My guess, squib round, bullet pushed up the barrel, second round loaded and fired. I've seen old Hornady with neck cracks fail to fire, extract and there's no bullet in the case, it's up the bore.

Wow thanks keep a eye on that got a CZ & hornady ammo. Good to know. Seen a Savage that split every neck, rifle got returned to the shop.

Don’t blame the rifle for split necks
Some HMR brass hasn’t been annealed before sizing to 17 cal and the brass is as brittle as

Add in galvanic corrosion “sticking” the projectile in the neck of the brass and when you fire it’s too much for that extremely thin brass

I’ve had it in my HMR, can’t remember which one, I’ve owned four of them. Projectile half way down barrel, I picked up the different noiseand checked, powder was black, still in the case. I think dampness. But listen to the noise when using.

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Originally Posted by 7mmsaum

Don’t blame the rifle for split necks
Some HMR brass hasn’t been annealed before sizing to 17 cal and the brass is as brittle as

Add in galvanic corrosion “sticking” the projectile in the neck of the brass and when you fire it’s too much for that extremely thin brass

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Split necks are common in everyone I’ve owned

It's not that uncommon as some would have you believe.
I've been through the blowing up of a T bolt and it only pushed the projectile half way down the barrel. In the last few weeks, I've been testing the ammo only to find split cases and I was getting the odd double to extract, but on the bench I was seeing a lot more split than normal, tentman+ gamely stood by as inspector Morse. In different ammo, like .22 find a batch and buy it and the newer the better.
Here's what I have learnt, the cases aren't annealed and the older the more prone to splitting. Hornardy have said it's usually ammo getting to the ten year mark that case are seen to split. Yet I don't find that to be the guide line.
Hornady recommends! Typically we like to see below 30 percent humidity and temperature of 65 to 70 degrees.
They have no control on shipping and storage when it gets here and how many years old is it, well at least three in the batches I've shot.
Now I am a great fan of the 17hmr in pest control and while major failures can happen, the idea is to take note of the batch and check for splitting.
Keep your ammo dry in good storage and keep an eye on the gas leakage in the chamber, because it will eat it at some point, if you shoot a lot.
I have taken to keeping the chamber ring clean, so not to add pressure to the neck of the case, the 17hmr have very tight tolerances that's what makes them shoot.
May we all continue to shoot another year.
KH

Here's a few of the small split cases, these gave no problem with ejection and didn't spread on the target.
But the brass isn't that good on inspection and I had two that went click. No batch buying on theses federales.
KH

Everybody ok? No serious injuries I hope.

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Originally Posted by 40mm

Everybody ok? No serious injuries I hope.

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I think some Poo came out

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Originally Posted by 7mmsaum

I think some Poo came out

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Better than blood or aqueous humour ( eye fluid)

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.

Attachment 240698Attachment 240698

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 :pissed off:

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

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Originally Posted by flock

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

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You've got to be kidding.
KH

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Originally Posted by flock

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

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You've got to be kidding.
KH

Haha -- no I'll use it but pretty weary, good thread, certainly opened a can of worms.
Had no issues thus far, just price of ammo has stopped me using it, more often.

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Originally Posted by Sharki

Better than blood or aqueous humour ( eye fluid)

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spontaneous incontinence ??

While on the subject, I had a brand new Anschutz .22..fired a few old CAC rounds through it, heard a dull pop, fired another round: there was a loud CRACK and it felt like someone had thrown a handful of sand in my face. It was fragments of the front end of the bolt. If I hadn't been wearing sunglasses, I would have lost an eye. I always wear glasses at the range now. The photos attached are of a .22 barrel which had been dropped in the mud then fired, and the second is of a D/B shottie inadvertently loaded with a double charge. The shooter lost 2 fingers.
Attachment 240970Attachment 240971

"Current standards (SAAMI) show the pressures in PSI. For the 22 Long Rifle and Magnum (and the 17's), the allowable pressure is 24,000 PSI."

Guy Neill
CCI-Speer Technical Services
866-286-7436


Interesting topic.
I had just assumed 17HMR was way more pressure than 22LR - that would result in the problems discussed here.
Not so. As the above quote from CCI rep.

I recently had to make the call for buying a new possum-rabbit gun.
I was very tempted to get a 17HMR, but in the end went with the proven 22LR (CZ457 Varmint) which has the quick-change barrel option, if required (22LR 22MAG 17HMR)
(.22LR CCI stingers come out of the barrel at 1550 fps) - If I was after some more exiting velocity.

Anyhow, I am really glad to have read this thread. I won't be getting a 17HMR in a hurry.
I am going to stick to my original plan, keep the CZ in .22LR for close subsonic work, and keep looking out for that rare beast, a .17 Hornet, and smack that ball right out of the park.
Cheers.

Hi bobbydazzler
As far as pest control ammo goes ! It's great in the fact it fragments very well.No bouncing the round or ricochets in my experience, the 20gn not so, I haven't tried the 15.5gn. I may try it for the built up areas.
If you read the thread, it's old ammo and humidity seems to be the main factors.
I have a handful of. 22lr and a. 22 magnun they are hardly used in the areas I shoot. I have heard the 22lr ricochet off sandhill County and that's no good on the life style blocks I shoot. I fired 30 odd last night and not one split case.
The A17 ammo is 100ft faster than the standard 17hmr and pressure is around 26,000 psi For he standard 17hmr ammo.
KH

@bobbydazzler Quick FYI I saw this listing you may be interested in: Weihrauch HW60J Sporter 17 Hornet Rifle https://www.trademe.co.nz/4498281817

I own 4 HW60J ( New model code HW66CH - Classic Hunter comes factory threaded with no iron sight) 2 X 22LR, 1 X 22 Hornet, 1 X 2222 Remington. I swear by them for accuracy, excellent engineering and fit. I bought the Hornet through r Reloading Supplies, they were $500 cheaper than the big green store. Marston are the importers and will happily advise you of who has stock in NZ and when the next shipment of the CH model is due. Good luck.

I'm reloading my 22 Hornet for less than .17 HMR rimfire and I'm not having the case problems the .17 HMR shooters are experiencing.

Hugh Shields Controlled Rabbit Culling Wellington - Kapiti

Hi Hugh Shields
The 17 hornet is a flat shooter for sure and of course the cases are annealed so not the likely hood of the same problem.
The 17hmr at night I hardly push it passed 150yrds, I find that is the comfort zone for me.
After that I use the 223 with 40gn vmax if the area is good for it and I have a K hornet that I am yet to really play with using 35 v max.
A little off the topic, however certain area's are good for a longer ranger at night, the flavors are many.
The night and the rest, all have their limitations and weight has a limit for me these last few years.
KH

On the change barrel cz rifles if there is any bulge on the head of a fired case I
Have given the barrel shoulder a skim in the lathe to tighten up the headspace
To more minimum specs
but all of the 17 rifles I have had through the door
90% have let go due to hornady Winchester or browning ammo

Cci or federal is better but have seen squibs from all manufacturers
If the stuck projectile is 5” back from the muzzle can usually
Get the projectile out and save the barrel and retain accuracy
Got a Sako quad barrel from a customer that was saved the first time
Using grease and 1/2x20 adapter but the second time it was stuffed