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PCP - HPA - C02 Gate => PCP DarkSiders Forum => : Gene_SC July 27, 2009, 08:47:29 AM

: I just bought a new PCP, now what do I do?
: Gene_SC July 27, 2009, 08:47:29 AM


Some Great Information for the new PCP buyer. A must read prior to buying a new PCP.



http://www.gatewaytoairguns.com/library/whatnow.htm (http://../../library/whatnow.htm)



Authored by Dave Dunn

I’ve been seeing lots of posts by new PCP shooters looking for info on various aspects of shooting PCP’s. The most common questions arise around filling the air tanks on the gun. I’m going to try to break it down in small pieces, but first, a short editorial.

Too many times I see a post that goes something like this- “I just bought a new (insert gun here), now what do I do?” People, the Internet is a phenomenal resource, use it FIRST! Most of the questions a newbie has have been asked and answered many times before, if you do your research first, you’ll be way ahead of the game. The other advantage to this process is that when you do buy that new shooter and have problems, you’ll be better prepared to deal with it. And don’t expect a rifle that’s advertised to do 1000 fps to actually DO 1000 fps. Yes, there are exceptions, even numerous exceptions, but as a general rule, expect real numbers to be 10-20% less than advertised. Also bear in mind that several name brands are importers ONLY, they don’t make a damn thing except money, and inflate the numbers to increase sales. RWS is a perfect example, they import rifles made by the Diana company of Germany. Look at the velocity claims of RWS/Umarex, then compare the same guns on Diana’s web site. Wanna guess which one is more in line with the real world? End of editorial, on to the meat and potatoes.

Okay, so you’ve decided to buy a PCP, or go to the Dark Side, as they say. And no, although I know the origin of the Dark Side reference, I don’t know how it got applied to PCP’s. Anyway, the first thing you’re going to need is a way to get air in that PCP. Basically, you have 3 choices.


Choice 1: Hand pump. Think bicycle pump on steroids, and you might want to think about some steroids for yourself if you choose to go this route. There are several models available, some under different brand names, but they all do the same thing, and that’s pump air at 3000 psi or more. I’ve used one a few times, I weigh 200+, and it’s a whole body workout that does nothing to improve my shooting. General consensus is, if you’re going to buy a pump, buy a Hill pump with DriPac. Compressing air also means you’re compressing water vapor in that air, and that means possible moisture problems in the gun. All of them have a way to expel the moisture, but the DriPac is considered the best way. Expect to spend $250-300 far the Hill pump. If you have a gun with a large tank, like the Air Force rifles, unless you really enjoy the work out, I don’t recommend pumping. Filling your new rifle is going to be the biggest bottle neck in shooting it, if it wears you out to fill it, you won’t shoot it as much.

Choice 2: Compressed air tank. This is actually multiple choice, because there are at least 3 ways to go here. The first and most common is the standard 80 cu. ft. SCUBA tank. SCUBA tanks need annual visual inspections, and hydrostatic testing every 5 years, but as long as they pass, they can be refilled. You’ll need to find a dive shop to fill them, and some can be touchy about this if you’re not a certified diver. But shop around, you should be able to find a source for air. Typical SCUBA tanks only go to 3000 psi or so, maybe 3200, that limits the number of fill per tank full. Again, the gun you choose makes a big difference. An Air Force Talon with it’s 490 cc tank and typical fill/refill level will get a half dozen or less fills from a SCUBA tank at 3200 psi, while an S200 will get 15 or more. Number of shots per fill is similar, but power and efficiency aren’t.

Next up is the SCBA tank. These are either fiberglass reinforced or carbon fiber. They’re available in various sizes, are generally filled to 4500 psi, and offer LOTS of air in a compact, light weight package. A 66 cu. ft. carbon fiber tank will fill the Talon 19 times, the S200 130!

So much for the good stuff, now the problems. First off, finding a place to fill to 4500 psi is a problem for many, myself included. Second, these things have a finite lifespan, regardless of hydro testing. 15 years from manufacture date, and it’s in the trash. And it doesn’t matter if it’s never seen service, unless you can fill it yourself, it’s junk. Keep that in mind if you’re buying one of these tanks used, ask the seller for the manufacturing date and the last hydro. And if buying new, be prepared to part with a chunk of cash, possibly more than you paid for that new rifle.

Finally, you can go with an idustrial compressed gas cylinder, think welding tank. You can get them filled with either plain air or nitrogen, in pressures up to 6000 psi. The typical tank is about 5 ft. tall, less than a foot in diameter, and weighs in at well over 200 lbs. This is NOT something you want to be hauling around with you a lot, unless you build a cradle and leave it in the back of your pickup. I’ve rented a nitrogen tank since I started with PCP’s, it’s 443 cu. ft. at 4500 psi. Using the same two examples, the Talon would get 125 fills, the S200 875. Or you could refill one of the smaller SCBA tanks for on the road use.

Because of where I live, this ended up being the most economical way to go without pumping. And since the vast majority of my shooting is either in my back yard, or short enough trips that I’m unlikely to need to refill my rifle, the lack of portability isn’t an issue, although I have taken it with me on one trip. Cost where I live is about $11/mo. tank rent and $60 for gas. I get 6 months or more per tank, and I tend to shoot quite a bit. I could get compressed air from the same supplier, but because it’s breathing air, it costs more. Extra steps required to certify it for breathing that aren’t needed with the nitrogen. There’s no difference in performance between nitrogen and air, and most of the manufacturers are finally admitting that. That said, although there are some other exotic gasses that could be used in a PCP, DON’T DO IT! There have been people that have used pure oxygen in PCP’s, if you’re really lucky you might get away with just destroying your rifle. Or you might just up the gene pool and destroy yourself. This is not something you want to get careless with.

Choice 3: Your very own compressor. This is what all PCP shooters dream of, but at $2000 and up, very few ever go there. Tough enough convincing the wife you NEED a $1000 rifle, never mind the rest of it. If you’re lucky enough to have the cash to burn, this with a carbon fiber tank is the way to go. And if you can go that way, would you please move in next door?

Okay, so now you’ve got an air source, but we’re not done yet. You need to get the air from the source to the gun. This is where the various adapters, whips, clamps, etc. come in. The proper fill adapter for your particular gun SHOULD come with it, but make sure before you buy, especially if buying used. These are specific to the guns, so just because you already have one for gun X, unless it’s the same brand and era as the new one, don’t expect it to fit gun Y. The other end needs to match your air source, if using a SCUBA tank, there are typically 2 options, either a K-valve clamp, or a DIN valve. An industrial cylinder will have a particular thread based on pressure and gas type, with the letters CGA followed by a 3 digit number. These are NOT interchangeable, so if you go this route, make sure to get the proper nut and nipple from your supplier. From the source, you need a minimum of a pressure gauge, a bleeder, and a hose of some type to atatch to your fill adapter. Most people use what are called Foster fittings on the end of the hose and on the adapters. This allows quick swaps between different adapters. The gauge will tell you the pressure IN YOUR GUN, not in the tank. Some guns have gauges on them, DON’T use them for filling, they respond much too slowly, you’ll overfill (A LOT!) if you use them.

Now that you’ve got all the parts and pieces together, it’s time to fill your gun for the first time. And like everything else airgun related, there’s a proper technique, but it’s pretty simple. If you’re using a pump, you have no choice, hook it up and start the work out. You’ll need to rest the pump occasionally (you won’t need any, or course), to let it cool down. How much pumping is needed will depend on how big the tank is and how far down you shoot it. Some pump frequently after just a few shots, some do a marathon shoot followed by a marathon pump session. The choice is yours.

If you’re filling from a tank, the technique can be summed up in 4 works: FILL SLOW, BLEED FAST. You want to just barely crack the valve open, and pay attention to the gauge at all times. On a first fill, you want that needle to just barely be moving, and if the tank gets hot, shut it down, you’re going too fast. On later top ups, the needle will rise quickly to about the pressure left in the gun, then slow down. Again, you want that needle to just barely be moving. Remember, you’re compressing a gas, and that heats it up. Too much heat can damage your gun or tank, so go slow. This can be a problem with some of the small gauges out there, as well as some of the tank valves. But do your best, your gun will thank you for it.

That should cover the general aspects, the details from here will be specific to the gun and filling equipment you choose. Hope this helps someone, and if I left anything out, let me know. Later.

Dave