While I have a carbon fiber tank, I still prefer the manual pump for topping off many of my PCP's. Dont get me wrong, I find no enjoyment in filling a large air reservoir from empty to 3000psi by manual labor, but for topping off, the hand pump works just fine.
I had been wanting to try out a new pump for a while, even though my old Logun pump had been working fine for years. I ended up selling the Logun and going for a pump that I'll not name here. The pump died within a week, as did it's replacement and so the vendor I bought it from refunded my money.
I then called Airguns of Arizona ( www.airgunsofarizona.com) and asked them what they had available. They had the Hill pump and the FX 4 stage pump. I had a Hill pump for a while and liked it well enough, but I was interested in trying out the new 4 stage so I went ahead and bit the bullet.
The new FX 4 stage pump is a manually operated hight pressure hand pumped used to fill precharged pneumatic (PCP) airguns with air up to 270 bar. The main difference in this pump versus others it in its ability to 'gear down' after around 150 bar by closing a port, thus allowing the user to fill gun up while maintaining a comfortable pumping level.
The pump arrived in a short while, packed well, and all components were secure in the box with nothing moving around to damage other items.
First impressions were that it is a nice looking pump, comfortable grip, footstand a little on the shy side, but no moreso than other pumps I've seen. The Micro Line hose is a welcome addition that is long enough to not have to contort guns that have fitaments at odd angles. The gauge is large enough to be read easily and is labled in BAR units.
I pumped a few strokes to find that it was a bit sticky in places. A quick call to Airguns of Arizona confirmed what I had suspected, that the pump just needed a bit of time to work in the factory lubricants. The sticky places smoothed out within a couple of uses and I've not experienced any other troubles.
Operation of the pump was the same as any other pump in that you pull the pump handle up all the way while your feet are at rest on the foot stand, then you push it down using your body weight to assist. Where the real news happens is when the gun reaches around 150 bar. At that point, it would seem you have two options... pump with a little more effort and a lot more efficiency, or make the pump strokes easier, but not quite as efficient. By closing the little valve at the top of the pump handle, the pump pressure is decreased by a significant amount.
I dont find it difficult to pump even without the valve closed and so I leave it open and the gun seems to be the most efficient pump I have used. I can easily top off any of my guns in record time and the pump barely gets warm. I used it to top off everything from small PCP conversion pistols all the way up to an AirForce Condor and a Quackenbush big bore. Could it be that the venerable Hill pump has met its match? Perhaps. I feel the FX4 stage pump is a true contendor and worth a look from those who must (or choose to) hand pump. Wether it will have the longevity of the Hill remains to be seen, but with the one year warranty from FX, I feel pretty confident.