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View Full Version : Economics of running a high pressure bigbore airgun



45 2.1
10-26-2013, 08:31 PM
I've studied the problem of charging and shooting a high pressure bigbore airgun. Unless you are hooked to the tank with a pressure regulator, you have a problem. You get maybe three shots and have to recharge on a single filling. That would be a hand pump or a precharged pressure tank. You either have a compressor and the high pressure addition for it or go to get the tank recharged. If you want long term self sufficiency you need the compressors and power (which seem to cost as much or more than the airgun itself).... hand pumping would be very tedious in a long term situation. Has anyone found a reasonable alternative?

melloairman
10-26-2013, 09:23 PM
I've studied the problem of charging and shooting a high pressure bigbore airgun. Unless you are hooked to the tank with a pressure regulator, you have a problem. You get maybe three shots and have to recharge on a single filling. That would be a hand pump or a precharged pressure tank. You either have a compressor and the high pressure addition for it or go to get the tank recharged. If you want long term self sufficiency you need the compressors and power (which seem to cost as much or more than the airgun itself).... hand pumping would be very tedious in a long term situation. Has anyone found a reasonable alternative?
Other than powder no . There is nitrogen but the same issues are present . You have to remember that in many cases a BB has the same energy as a hand gun and some times more . And it is done with a chamber pressure of 2000- 4500 psi . So it takes a large volume of gas to get the same results . I shoot only air now and have a compressor and I do regulate and tether . The savings is in no powder, primers or brass . I use free reclaimed lead . So it now cost me nothing to shoot . Cost of compressor and equipment is really no more than reloading equipment if I factor in the savings in powder ,brass, and primers .Marvin

MT Chambers
10-27-2013, 01:00 AM
Not to mention how one would use one for hunting or field use, all airguns(PCPs) are a compromise between power and number of shots....When they developed the Wolverine they had it up to 150+ fpe, but had to cut it back to 100 or so to get a reasonable amount of shots to a fill (12), to enable field use. If I wanted to be tied down to a bench for shooting, I'd go for a heavy barrel pb, much flatter shooter, and more accuracy.

45 2.1
10-27-2013, 09:50 AM
OK, that's what I thought. Does anyone make a bigbore airgun that has a regulator for constant pressure release instead of a valve?

melloairman
10-27-2013, 10:48 AM
As far as the BB regulated rifle I really do not know of one . And yes most of these rifles are set up for max power which lowers shot count , gives a large spread between shoots , and waste air unless you feel you need every pound of energy . It is the same as a PB . To get a small increase in energy it takes a lot of gas . I set my rifles up for beech work and use no more air than needed to get the job done . I prefer air over powder for bench work . With the rifle tethered and regulated every shoot is with in 10 fps normally of each others with a minimum of recoil that disrupts accuracy and my shoulder . As far as hunting the spread in energy is some times not as much of a problem as one might think at the normal 50-75 yard range that most stay within . I use this calculator to give me a idea as to what I need to do to get to where I want to be . It is close enough to get me on paper and dial in from there . It sounds good to say I can shot a 250 grain bullet at 950 fps but is it really needed for accuracy and energy . At a high cost of air consumption . Marvin
http://www.handloads.com/calc/index.html

Frank46
10-29-2013, 12:26 AM
Google David Quackenbush. He makes big bore air rifles. Frank

45 2.1
10-29-2013, 08:45 AM
Google David Quackenbush. He makes big bore air rifles. Frank

He is the guy who started me thinking about BB airguns. Unfortunately, he didn't have too much to say about keeping one charged over the phone or the cost involved... just that he used the Benjamin air pump (which didn't do well in the reviews). Hence the question to find out more about what is involved.

Pakprotector
10-29-2013, 08:56 AM
The reg'd rifles need two chambers to store the air, one firing chamber downstream of the reg, and a bigger one ahead of it. The volume of the firing chamber should be on the order of 1cc per FPE delivered. For light weight stuff, half that seems acceptable, with a slightly higher pressure set point v. the 1cc/FPE spec. Expand the scale from a 40 FPE, .22 cal to a 500 FPE, .357 and you're looking at a 300-500cc plenum to fire from. Few rifles have storage that large in total, and size costs mass.
cheers,
Douglas

Multigunner
10-29-2013, 11:50 AM
Seems like the detachable ball reservoirs used by some of the early sporting air rifles might be a better idea than the larger capacity fixed tanks.
Say several quickly replacable smaller size air tanks pre charged that you could switch out after every two or three shots.

There are shot to shot pressure regulated CO2 match grade air rifles, perhaps the methods used for these can be adapted to PCP air guns.

Silver Eagle
10-29-2013, 10:24 PM
Some of the European rifles do have removable reservoirs. As well as competition grade pistols and rifles. The AirForce brand of airguns also has removable reservoirs.
There are better pumps out there than the Benjamin as well. How much pressure you have in the reservoir determines how many pump strokes it will take to refill. Please note that the reservoir is only partially emptied each time. For example, fill to 3000 PSI, shoot down X amount of shots to say 1800 PSI. Stop, fill, and continue shooting. Most gun operate best in the accuracy or power curve of the fill.
There are also carbon fiber tanks available that take up to 4500 PSI that are light enough to be carried into the field.