SpudFiles

I don't know if I should get a pressure gauge for my new gun. It's going to be a simple barrel sealing valve system. I don't know if I need a gauge or not though.

If you have a guage on your pressure source, you don't need one on the gun itself.

well, does you bike pump/compressor have a guage? if so, i wouldnt bother, if they dont, its a must.
i personally have never used a guage on my guns, becuase my pump has a guage. however the next gun that im going to build will have 2 guages, one for the regulator, and one for the chamber.

its all up to preference, and your pump.

If you're confident in it not leaking and are always aware of it being charged or not then I'd say stuff the gauge and just rely on the one on your pump.

If you forget things like whether you've charged it or not or leave it for any substantial length of time before firing then I'd nail a gauge to it.

I don't use a gauge because I always fire within a couple of mins of charging it and I know its airtight.

I never use gauges, now I have a gauge on my pump but before I just found out the volume of my pump and chamber so I could get a pressure estimate per pump. An easy way to do it is to get a tire gauge that you press up against the schrader valve to get the reading. You may lose a couple psi, but nothing large.

The gauge on the compressor will read different to wahts in the gun unless its a bike pump. An air compressor only has a gauge for pressure in tanka dn pressure regulated. If your chamber is medium size you can get a 15psi difference between regulated pressure and the actual pressure in the gun.