Jds airman tank block question

[melvin]

I received a project rifle recently and the tank block is installed with the retaining screws heads on the tube instead of seated into the tube like the valve would be. Is this an issue? Or should I ream the holes in the tube out to get the retaining heads to be seated like the valve is?

Here is a pic.

[mr007s]

My block is mounted as your photo but I also added two more. I fill to 3000psi and the reg is 2000 psi

[FuzzyGrub]

I received a project rifle recently and the tank block is installed with the retaining screws heads on the tube instead of seated into the tube like the valve would be. Is this an issue? Or should I ream the holes in the tube out to get the retaining heads to be seated like the valve is?

Here is a pic.

I'm not sure what "good enough" is, but the stronger of the two would be reaming out the holes.  Make sure there are flats at the screw holes, like the valve has.    It puts the stress on the larger head vs the smaller diameter threaded part.  The tube may be the weak point.  This is one of those calculation question for Bob.   

[rsterne]

The question of whether it is "good enough" depends on the pressure you are running.... Without knowing the size of the tube and the size and material the screws are made from, no proper answer can be given.... If that is a QB / 22XX / Disco sized tube, using #8 high-tensile, low-profile SHCSs (which is what they appear to be), my only comment would be that it should be an improvement over the stock QB79 tank block because the holes are further from the end of the tube, which was a potential weak point....

Personally I would drill the holes in the tube out to the size of the screw heads, and spot face the spigot on the tank block so that the screws tightened against it.... while leaving the top of the heads flush with the outside of the tube.... You would have to be certain that doing that did not compromise where the O-ring seals, however....

Bob

[melvin]

The question of whether it is "good enough" depends on the pressure you are running.... Without knowing the size of the tube and the size and material the screws are made from, no proper answer can be given.... If that is a QB / 22XX / Disco sized tube, using #8 high-tensile, low-profile SHCSs (which is what they appear to be), my only comment would be that it should be an improvement over the stock QB79 tank block because the holes are further from the end of the tube, which was a potential weak point....

Personally I would drill the holes in the tube out to the size of the screw heads, and spot face the spigot on the tank block so that the screws tightened against it.... while leaving the top of the heads flush with the outside of the tube.... You would have to be certain that doing that did not compromise where the O-ring seals, however....

Bob

It is a disco tube,1400 psi output on the bottle, cannot really answer the question on the screws unfortunately other than the definitely seem more substantial than the qb screws which is zero help for anyone. (Assumption would be that they are what comes with the tank block from jdsairman)

Thank you all who replied. I appreciate it.

[Ribbonstone]

Seldom got in trouble for making things stronger....often got in trouble the other way around.

Depending on the quality of the screws, would personally trust it at 1400psi....but that's me.

[rsterne]

Providing you have a 1.8K burst disc on the output side of the regulator, you should be no worse off than a stock QB79 setup, IMO....

Bob

[melvin]

Thank you.