It Wasn't Even Friday 13th.

PLEASE HELP TO FUND ARCHERY INTERCHANGE

albatross

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I was shooting some ACC arrows. Correctly spined for my recurve draw weight. I had shot about 18 arrows when this happened. The plunger has not jammed. I checked it immediately. I think the pressure of the plunger reacting to the arrow on release proved too much for this item. The thin wall of the threaded section was not up to the job. I was lucky not to have been taken to the local A&E. I won't be buying a replacement from the same manufacturer I can assure you.
 

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dvd8n

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UNF threads are meant to be cut with a radiused bottom. I'm guessing that the thread was cut too sharp at the base which will have decreased the amount of metal thickness in the barrel and caused a stress raiser just where it could do the most damage Just speculation, though.
 

albatross

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I think the nose of the barrel was pretty flush with the rest side of the riser. I shoot a fiberbow carbon riser. So quiet a bit of the barrel was inside the riser. I unscrewed the locking collar so that the break could more easily be seen in the pic.
 

Stretch

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That‘s just weird. I presume the collar has been moved after failure? Did both sections of the arrow pass the riser on the window side? Looks like the break is close to the back of the arrow.

I don’t see how the breaking button could break the shaft as you can shoot the arrow without a button and with a rigid button. Seems more likely that the initial failure was the arrow?

Either way looks like the button barrel is made of tinfoil. I have seen other plungers break (Shibuya, AGF and Beiter) but all had had an “accident” prior to the failure and it didn’t make any difference to the shot.

Glad nobody got hurt!

Stretch
 

albatross

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140mm from the end of the carbon. The fletched section went right and the front section went left. The 'Bang' was the biggest surprise I heard in along time!
 

Timid Toad

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Sounds like you had an arrow failure that broke your (admittedly thin walled) button. always look for chips H cracks and dinks in the carbon all the way up. Especially if you've clipped the edge of a round boss with a miss.
 

Stretch

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That seems likely if the back of the shaft went button side. Shaft failed completely under loading. That is some scary stuff. I’ve seen it with ACE D series but never with an ACC And in that case both bits went the right side of the riser.

The bang is most likely because the arrow failed before the end of the power stroke then what was left attached to the string weighed almost nothing. Kind of like a semi dry fire. Same thing happens if the nock breaks on release. Lots of energy that goes into the bow instead of the arrow.

Note to self: go check all your arrows thoroughly :rolleyes:

Stretch
 

albatross

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A bit scary when it happens! I'm going to order a Beiter as a replacement. Costs a lot more but it should have better quality control. As they say you cannot take your money with you when you die - so I may as well buy something of better quality for the sport I enjoy.
 

Rik

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That seems likely if the back of the shaft went button side. Shaft failed completely under loading. That is some scary stuff. I’ve seen it with ACE D series but never with an ACC And in that case both bits went the right side of the riser.

The bang is most likely because the arrow failed before the end of the power stroke then what was left attached to the string weighed almost nothing. Kind of like a semi dry fire. Same thing happens if the nock breaks on release. Lots of energy that goes into the bow instead of the arrow.

Note to self: go check all your arrows thoroughly :rolleyes:

Stretch
I can testify to that with nock breaks. It's rather boggling to see a string loop cut lengthways down a limb. Kind of rams home the forces involved
 

little-else

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another possibility is an overdraw allowing the arrow to become lodged behind the button, albeit momentarily. That would likely snap the arrow behind the riser as the now broken button shaft tries to rotate forwards ( the pitch of the thread would allow a millimetre of movement before the thread fouled itself) with the front of the arrow whilst the back end is forced over to the right and then straightens up after the break allowing it to pass the right hand side. So what you have left is the result of 2 unlikely eevnts occurring together.
a piece of threaded metal can fail almost at any time due to fatigue and it wont have had to be overloaded, a small defect being the locus of the forces applied to it. Standard testing wil predict how long something will last but that doesnt tell you what a minimum might be.
i once examined a bolt from the ceilig of the Royal Festival hall that had failed, bloody great thing that had just done its job for 50+ years and then suddenly snapped dropping parts of the ceiling onto the audience
Microscopic examination showed a number of microcracks near to the point of failure and signs it had started rusting, all associated with striations from the threading of the bolt.
In an ideal world these things get treated where critical but for a button you will find the next one will last thousands of times longer and it is down to bad luck as the material is nominally more than up to the job. I have seen a compound bow snap in two due to a small flaw in the casting of the riser that was miles away from the surface but he cycle of loading/unloading did for it in about a year when you would expect at least several decades of life.
 

Timid Toad

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That is why I was asking about the clicker - enthusiasm for a return to archery, big draw, arrow gets stuck and bang. Easy without a clicker.
 

Stretch

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I think the break would be on the other side of the button collar and the archer would be in A&E :p

That idea scares the *%@£ out of me.

Stretch
 

Timid Toad

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Albatross has moved the button collar... and yes, even if it was enough to deflect the arrow into the riser hard enough to break it it's a scary thought.
 

Stretch

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Agreed. I know the OP moved the collar but he just moved it down I think. If it had been taken out with an overdrawn arrow the tip side of the plunger would be mangled. The break is on the other side of the barrel surely? Especially in. Fibrebow which is a thick riser so would support the barrel.

Not that it matters :eek:

Stretch
 

albatross

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I'm back again. NO Overdraw. The arrows are correctly spined for my draw weight. I have a Beiter clicker and always draw through it. I think that the arrow, for whatever reason, exploded on release and the rear end went to the button side of the riser with the result shown.
 

Steve1968

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If you have a look on website of king arthurs adviser, there is a review for that make/model pressure button. Not very good.
 
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