Sprocket:
I shoot a new Daystate Regal XL in .177 at about 20 ft./lb. (925 fps)...This is as this gun came set for the US market. ...I acquired this gun brand new about 6 weeks ago and it shoots 70 good shots if the air cylinder is filled to the MAX 240 BAR (about 3,500 PSI) and 48-50 good shots if only filled to 200 BAR...The gun is darn accurate out of the box...
I fill it with an aluminum Scuba to 200 BAR, and if the Scuba is filled to 200 BAR (Full capacity) it gives me somewhere like 10-12 refills before I need to top it off...I shoot above 125 BAR which is the point where the velocity drops down in the curve more than 2-2.5% (below 900 fps + or -)...
.From 240 BAR to 125 BAR (70 shots) you have a consistency of about 1-1.5% (9-12 fps) which is extraordinary for a gun that is not regulated...The slingshot hammer system in this gun seems to be excellent and very efficient...I bought an Altaros regulator and tested it thoroughly, it is a good regulator but the gun doesn't need it and I removed it. I got the very same 70 shots but at a lower 890 -870 fps. with about 1% spread...EXCELLENT! but then I wanted 925 fps. and an additional variance of 4-5 fps. that the unregulated gun provides makes no real difference in accuracy...
For what I use this rifle (Pest control, plinking, some 50 + yard fancy shots, and some hunting, this gun, this velocity and this accuracy is more that I really need.
I started hand filling PCP's some 20 years ago or so with hand pumps, I bought a Hill 8-9 years ago as a backup for whenever we go to competitions...One time there was no air available and we didn't bring the air tank with us thinking that we would get air at the range...Well, the competitors were kind of not too friendly or willing to provide us air and we did not shoot after driving 300 miles...I used this pump 2-3 times and is quite a work out, the pump I believe is for 200 BAR but I forced it up to 240 BAR recently with no issues...
Pumping is OK if you give it some time in between filling and shooting...Specially if you are going to shoot accuracy at long ranges and also helps the pump in not overheating...
500+ pellets a week means about 7-8 full 240 fillings in this gun, it takes roughly 150 - 170 pumps per fill on my gun and with my Hill pump....I can fill the cylinder in about 15 -20 minutes taking breaks and I sweat somewhat, I am not that young and are not ready for a hart attack so I take it easy...There are some posts over the Internet in how to use a shop compressor as a first stage pump in combination with a hand pump, you alleviate about 50% of the load and makes pumping more appealing or so they say... I haven't tried it.
So don't be discouraged, if you shoot daily this means a daily work out of 20 minutes and that is not too bad...If you shoot mostly over the weekend, then 2-3 cycles per day can become quite a workout, but is doable and if you get into the shop compressor thing, that seems not too bad...
Another alternative is to design a crankshaft and attach the pump to a motor with a transmission (cheap on eBay), some 10 RPM per minute for keeping the pump not too hot and for filling your gun in 15-20 minutes while you drink a very cold beer will be very easy to do...In my youth days I did this with a bicycle hand pump with a 30 RPM high torque scrap motor that my dad had in his shop...That was my friend's club refilling station for a full summer until the pump broke and my dad had some compassion and got us a small shop compressor....Welcome to the first world he said!
Regards,
AZ