Any engineers know why the metal dangerously failed on DIana trigger

[blooregard]

That design is prone to failure, as there is a stress raiser in the right angled corner...it is where the crack propagated from. If this is made with any type of secondary flaw such as a void in the steel or any imperfections / impurity, then it will do exactly as it has here.

One would hope that this Safety Critical component is not made of any Sintered or Cast process, as that would surely result in a metal part not fit for purpose if any minor flaw was present.

Take a look at HW Sear, which is a very much tried and tested piece...it has no significant right angle to act as a stress raiser.

Diana should look at this as a matter of urgency. If there was an accident then they would have liabilities I suspect.

What you say is perfectly reasonable, but lets not assume Diana are less experienced or competant than yourself when it comes to design of a component, and lets also not pretend that a HW component is incapable of failure. Despite the glowing reports the HW rifles often receive they are not without their ridiculous oversights.

Without being present when a component is designed it is very difficult to place liability as the reason for the design may be perfectly defendable.

Any component in any device can fail, when it comes to guns that is why you ensure you know what their condition is and you keep them pointed in a safe direction.

[lensman57]

Looks like a failure due to either stress or fatigue fracture to me but it would have been helpful if a photo of the face of the failed parts were taken. Without that it is difficult to pinpoint the cause. It may just be that the metal used in making the part was defective in one way or the other. Did it mention anywhere how old the gun was and how frequently it was used?

A.G

[Barryg]

Looks like a failure due to either stress or fatigue fracture to me but it would have been helpful if a photo of the face of the failed parts were taken. Without that it is difficult to pinpoint the cause. It may just be that the metal used in making the part was defective in one way or the other. Did it mention anywhere how old the gun was and how frequently it was used?

A.G

Yes it says in the thread I posted that it is a new gun.

[look no hands]

Well this is very coincidental, I've had a T06 conversion kit for a while which has been in a XS208 and is now in a 90's Diana 34, I recently bought a Original 45 barrel to fit to my 34 but it wouldn't lock up properly on the breech due to the detente ball being smaller than the 34's, after firing a couple of shots I cocked the gun and decided to give the barrel a bit of a slam shut to see if would seat any better, the gun went off on it's own without my finger being anywhere near the trigger (luckily pointed in a safe direction), it wouldn't cock after that, I haven't stripped it down yet but I think it might be a job for today to see what's happened but I think this may be the problem.

I'll keep you posted.

Pete

[Barryg]

Well this is very coincidental, I've had a T06 conversion kit for a while which has been in a XS208 and is now in a 90's Diana 34, I recently bought a Original 45 barrel to fit to my 34 but it wouldn't lock up properly on the breech due to the detente ball being smaller than the 34's, after firing a couple of shots I cocked the gun and decided to give the barrel a bit of a slam shut to see if would seat any better, the gun went off on it's own without my finger being anywhere near the trigger (luckily pointed in a safe direction), it wouldn't cock after that, I haven't stripped it down yet but I think it might be a job for today to see what's happened but I think this may be the problem.

I'll keep you posted.

Pete

If you're trigger is broke in the same place DIana have a problem, post any pictures that you have if it's broke.

[derekj]

I have a Diana 440 TH which has t06 trigger. Its now in sales

[andrewM]

Barry, this is a grave complaint and it seems that it is not being taken sufficiently seriously, although we shall have to wait to see the result of Diana's investigation. Their agents/distributors, here, should be on top of this at once and it should not be necessary to have to go directly to Diana.

You could, however, speak to the 'trading standards' division of your local council and the 'health and safety' department too. This is something that they would take very seriously and they have the power to close down a business if necessary. Assuming it is a new rifle, it should be replaced, new for new.

The above steps are lines you might not presently wish to take but I think you might drop Diana an email to inform them how strongly you consider this issue to be, which could, in extremis, have resulted in a fatal injury. You might also care to inform them of the relative disinterest of their agents - assuming this to be the case. Indeed, you may wish to inform the agents (go to the CEO) of the steps you will be taking (as above) unless this problem is solved entirely to your satisfaction. You might also inform Diana - as necessary - that their reputation is at stake and that a keen interest is being shown on the blogs.

I am sure that will have a salutary effect and, frankly, it should go all the way to the top of Diana and land on the CEO's desk.

The production number should be quoted - which will enable Diana to check to see which staff were on duty and attending to which parts of the weapon at the time.

A carefully worded letter always has a sound effect and it should always go to the top. Fortunately, there was no injury but it would not have been difficult to envisage a situation where that might have occurred.

Regards
Andrew.

[Geezer]

All good advice, but the trigger in question broke in the US, not here.

[TORNADOS7]

Judging by the looks of it that part's not machined but cast, my suggestion would be a porous casting probably using inferior metals, not an uncommon issue in this day and age where the recycling of metals is becoming more and more common...

Recycling is all well and good but on certain items (mainly high stress items such as your seare) the use of a more pure source of steel should be a given, recycling involves steels of all grades being re-melted then extruded, drawn or cast thus producing an inferior quality of product hence the lower stress tolerances and higher breakage rate we see more and more of these days...

[oldgeezer]

It could be slag in the casting or the loud bang could be the rifle detonating upon firing blowing the piston
back and breaking the trigger catch.

Detonation.
Sounds right to me.What else would explain a "loud bang" on firing.
If it was a straight forward failure under the strain of holding the piston back then it should make no more noise than a standard trigger release.

[harvey_s]

Other than a heads up of a potential issue for certain RWS Diana owners I'm unsure what purpose this thread serves...

The OP does not appear to be the gun owner or in contact with Diana directly.
The gunsmith who is working on it emailed Diana on Thursday and today is Sunday.
The broken part is back with the owner and there are no photographs of the internal broken faces.
So pretty much useless for forming a useful theory as to the cause...

But, of even more concern is...

The rifle is also supposed to be only a few months old and rather than being returned to Diana, has been returned to a gunsmith who has been apparently told he is unqualified to work on the rifle in question.
So, armed with this information he then orders and fits an exact duplicate of the part he considers unfit for duty!
He then returns this to the owner and he "might call Umarex", but he "doesn't want to make fuss" - but appears to be quite happy to post on internet forum about how potentially serious this is!

Mmmm, perhaps its just me - but there are some real issues with this - mainly centred around the gunsmith in my opinion.
Would you have sent the gun back to the owner without a satisfactory response from either the importer or manufacturer?

[look no hands]

Well the rifle has been stripped and the offending article is a sheared top hook (SR279 on Chambers parts drawing)

https://www.gunspares.co.uk/products...-Trigger-Unit/

Now do I inform Diana of this problem or just buy the new part and fit it?

Pete

[airgunnut]

Well the rifle has been stripped and the offending article is a sheared top hook (SR279 on Chambers parts drawing)

https://www.gunspares.co.uk/products...-Trigger-Unit/

Now do I inform Diana of this problem or just buy the new part and fit it?

Pete

Well now you might have a problem, if the gun is only a few months old it will still be under warranty BUT as its been striped by someone other than a Diana approved gunsmith, the warranty would have been voided.

[Barryg]

Well the rifle has been stripped and the offending article is a sheared top hook (SR279 on Chambers parts drawing)

https://www.gunspares.co.uk/products...-Trigger-Unit/

Now do I inform Diana of this problem or just buy the new part and fit it?

Pete

Pete please post a pic.

[look no hands]

Well now you might have a problem, if the gun is only a few months old it will still be under warranty BUT as its been striped by someone other than a Diana approved gunsmith, the warranty would have been voided.

Basically the trigger mechanism and piston where bought as a T06 conversion kit for T05 triggered Diana 34's, originally it was purchased to go into a Chinese XS208, which it was and performed faultlessly, I then purchased an older 1990's Diana 34 and fitted the piston and trigger mechanism to that, so basically there will be no "New gun" warranty, the T06 conversion kit was purchased about 3 or 4 years ago from Germany and hasn't really done that many shots in either rifle (no more than a tin of pellets), I'm not into wanting to sue Diana or even get a new bit for free (but it would be nice if they did replace it for free) but it's the future failures in other rifles that concerns me and if I found out that someone had been injured because of the same problem then I'd be most upset.

Pete