Other Xisico Sentry Burst Disc?

I have an oldish Xisico Sentry, thay had at one point totally gassed out while I was filling it. I had just assumed that a burst disc had gone bad on it, and just put it away, being as i have many other guns to shoot. Now that winter is coming I have some free time on my hands , and I'd like to get it up, and running.

Does this issue sound like it may have been caused by a burst disc? And if so; where in the gun is this disc located? An exploded diagram would be helpful if anyone has one handy. Additionally if anyone knows the size of said burst disc, and where one could be had, that would be great as well. Any insight y'all could offer is greatly appreciated. TIA!
 

From a casual look at the exploded diagram, I'm not seeing a burst disk. My guess would be an O-ring was beginning to extrude and gave way as the pressure was rising during the fill. My advice would be to try filling and listen for where the air is escaping, however considering the OEM O-rings from most Chinese-made PCPs are of dubious quality (including Xisco specifically), the best route would be to take the time to do a full reseal.
 
Looking at the diagram provided, mine appears to be a somewhat different variant. As I understand it the Sentry had a number of renditions. While I haven't completely stripped it down; I have come across what I think may in fact be a ruptured burst disc. Any insight would be appreciated, as I've never taken a PCP apart before.

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However...

On the under side of the compression tube is a threaded set screw with a hole drilled down the center. Upon removing this set screw i see what I think is in fact a burst disc which has ruptured. Though I cannot be sure because I've never broken down a PCP air rifle.

It appears goldish in color, and appears to have been press fit into the hole by the aforementioned set screw. In addition this disc appears to have a hole caused by a tear, rather than an intentional means such as a drill, as it still has the center attached by a scab.

I tried to post pics, but for some reason the site won't let me citing some security issue, whatever that means. (Nevermind. Got the pic to take!) Anyhow, given my crude description; do you think that perhaps this may afterall be a burst disc issue, and perhaps the item I came across might be said burst disc? TIA...
 
Have you tried calling Mike at Flying Dragon at about noon? I believe that Captain o-ring on Amazon has burst disk assembly and I believe that the Sentry came with a few Burst disks. My 705-9K fills to 3000 psi.
I think mine may have come with some too. But it's been years now, so I can't be certain. I'll have to look around. First though I have to pinpoint the problem so Mike can help me resolve it.
 
I think mine may have come with some too. But it's been years now, so I can't be certain. I'll have to look around. First though I have to pinpoint the problem so Mike can help me resolve it.

Should be a bag of o-rings with 2 burst disks in it.

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I'm gonna have to dig through my accessories stash. If it came with the gun; I still have it.


Somewhere...
 
Should be a bag of o-rings with 2 burst disks in it.

View attachment 511472
Found it! Got her back together, and am dialing her back in. I noticed something interesting while reassembling it though...

The port that hides the burst disc, and burst disc plug; correlates with a hole made in the stock. This hole is then covered by the forearm assembly. However the forearm assembly even has markings on it tha suggest a hole mighta/coulda been present prior to a mold change?

Can't tell if this is the remnants of a previous variant. Maybe a different fill port location, or possibly a gauge?
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It would be nice if I could have my pressure gaugue there, instead of on the end of the tube. Staring at the muzzle while filling has never set right with me...
 
Glad that you got it back together!
“It would be nice if I could have my pressure gaugue there, instead of on the end of the tube. Staring at the muzzle while filling has never set right with me...”
I agree with this, however, this design is the simplest to maintain tube volume. I have a rectangular inspection mirror that I set at 45 degrees on a flat surface at my fill station to watch the gauge.
 
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