Tuning DAR Gen II .22 Fill Probe Leak Issues

[cmhughes]

Got a DAR Gen II .22 rifle about 10 days ago and attempted to fill it to the recommended pressure with an Air Venturi G9 hand pump that I purchased a couple weeks previously. The hand pump held pressure fine when tested, but when I attached the DAR fill probe and attempted to pressurize the rifle, air was leaking from the quick disconnect fitting. Upon further inspection, the fill probe diameter is about a half mm smaller than the quick disconnect fitting on the port and will not seal properly. I did a quick fix by shoving a small O-ring on the end of the probe to seal it which worked temporarily; however, the O-ring got nicked and will probably not be a permanent solution. Thinking that I may have received an out-of-spec G9 pump, I exchanged that one for another, but have the same issue.

Is there any way to fix this with something like Teflon pipe thread tape on the fill probe, or should I look for some other brand of fill probe that may fit the DAR rifle - if one exists? If so, what brand of fill probe would work on this rifle other than the one supplied? Are there any other solutions/suggestions? Soon enough the DAR will run low on air and probably won't be much good unless I get close enough to my quarry to smack them with the rifle butt.

Thanks

 

[paperp]

HI I WOULD JUST CONTACT JOE AT DAR THEY HAVE GOOD CUSTOMER SERVICE AND SHOULD REPAIR OR REPLACE?! PAPERP

 

[nervoustrig]

This may or may not work but it’s easy to try. I expect the Air Venturi pump is made in China and as such probably uses metric O-rings exclusively. Try removing the O-ring that is inside its female Foster fitting and replace it with a -010 which is an imperial/inch size (AS568 being the technical classification). This size O-ring has a cross-section of 0.070” versus a metric M1.5 (0.059”). Thus it will take up precisely the half millimeter you measured and may help it seal properly straight away.

 

[cmhughes]

Yes - Chinese made (as most things are these days). In fact, DAR said the Gen II is imported, which probably means these are made in China as well. Where would I start looking to find an O-ring of this size?

 

[nervoustrig]

Local hardware stores. Plumbing section typically. The $10 clamshell assortment at Harbor Freight has the -010 size and a few other common sizes. Lots of them you’ll never use but it pays for itself by the third time you retrieve an O-ring from it.

 

[Gerry52]

Mcmaster-carr has o-rings of all sizes Standard and Metric. When I had guns that required fill probes I always had spares on hand. An inherent problem with fill probes. 

 

[cmhughes]

Sorry - one last question: when I find a larger O-ring, how do I get the original out of the quick-release fitting since it is deep in there? When I took the quick-release apart, it only gave me access to the filter. DAR sent me another probe, but it is still too loose, so the only option at this point I assume would be the O-ring.

 

[biohazardman]

Dental pics are the tool I use and they werq very well. In a pinch you could probly use a big paper clip bent on one end. Sharpen or smash the end with a hammer if you have problems it as it will help you get under or stab the ring to pull it out. Be careful not to scratch the sealing surfaces.