It's your bottle, not enough pressure in it to blow up to 200. Put an inline gauge on your bottle and I'll bet it only blows up to 160, if your guns were out, why are they both blowing up to the same pressure as your bottle, Si is right to a point, if damp air is used to blow up your bottle, the gauge used on the bottle filler will read full, that's because dry air compresses more than air with moisture in it. Turn your bottle upside down, not connected to your gun, and blow a stream of air at a dry paving slab or some thing like that and see if it leaves a moist patch, if it does your air i