Pre-charged Pnuematic Air Rifle
|The CROSMAN WEBSITE http://www.crosman.com|
|Well made and well ballanced gun, this is the lightest full sized PCP I've ever shot. The gun is available in .177 and .22 calibers, and can be purchased as a package with gun and hand pump, or rifle alone.|
|I was on my way home from a morning deer hunt when my cell phone rang, it was the project manager responsible for a new rifle being manufactured by the American airgun giant Crosman. She told me that my name had been brought up as a possible candidate to try out an innovative new airgun design Crosman was working on. She stated that they anticipated this product would have a major impact on airgun hunting in this country, and wondered if I might like to get a pre-production gun for testing. Well of course I was interested in learning more.
about this pneumatic (PCP) design based on the companyís long established 2260 CO2 rifle. I have a couple of these rifles in my collection, and have done a fair amount of customization modifying the valves and triggers for use as a platform to build my own pcpís. Therefore, the idea of Crosman basing their new PCP on the venerable 2260 design resonated with me, as the core technology is well proven. And while the gun leveraged the established 2260 technology, optimizing it to run on high pressure air was not just a matter of slapping a high pressure air reservoir on in place of the CO2 reservoir. A redesign of the valve, the development of the valve anchoring and installation, and a new filling port were required as well.
Nor was the intent simply to build another PCP. While this type of airgun is not widely known in North America, in much of the world it is the airgun technology used by the greatest number of hunters. To meet the demands of American hunters the rifle needed to be positioned at the right price point, British airgunners routinely pay more than $1000.00 for their pcps, and perhaps hundreds more on filling gear. But unlike much of the world, American shooters have access to low cost firearms, making the high price or European airguns less attractive to many shooters here.
To gain acceptance in our market, Crosman also needed to deliver a power source that could be independent of expensive filling gear, such as compressors and high pressure air tanks. Hand pumps, which resemble nothing more than a bicycle tire pump on steroids, have been around for years and offer an attractive alternative. But if you have a gun that needs to be charged up to 3000 psi, you may have to apply a couple hundred pumping strokes to fill the onboard reservoir. So if the gun could be designed to work at a lower pressure but still deliver the power and shot capacity, a hand pump could be used with much less effort and free the shooter from dependency on a compressor.
And from these requirements, the Benjamin Discovery was developed. The first serious airgun for many of us was the Benjamin multi-pump air rifle, and Benjamin has always been synonymous with high production quality. When Crosman acquired this company many years ago, they (wisely in my opinion) decided to retain the Benjamin name as their premium brand. The Benjamin Discovery is a gun that delivers on the requirements set forth; it is based on a known technology, it is designed to yield high velocities at a relatively low fill pressure, and the price point for a package consisting of the rifle and the pump is well below what is typically paid for the gun alone. It has also been designed to implement a feature called Dual Fuel TM technology, which permits the gun to operate on compressed air for field work or with CO2 for plinking and target practice when lower velocities are desired.
To set up and get a feel for the rifle I started off on the bench. This is my normal procedure to see what pellets perform best, as airguns can be quite finicky about which projectiles yield the best all around performance. After assessing how the gun grouped and what velocities were achieved using a variety of different pellets, I headed out squirrel, rabbit, and pest hunting. But before we get to the hunting, letís take a look at the gun and how it performed.
The Discovery is a compact rifle that weighs 5 lb 2 oz, and is 40 inches overall with a 23.6 inch barrel. The first thing that struck me when I unpacked the shipping crate was that while the gun bears a strong resemblance to the standard 2260, there were also some striking differences.
The stock on my test gun is a nicely figured hardwood that has a more finely shaped pistol grip than the standard 2260. The depth and width of the forestock is a bit more substantial as well, which is needed to house the onboard pressure gauge that is situated a few inches in front of the trigger guard. The stock is finished with a buttplate made of high impact plastic, that work well enough as there is really no recoil to speak of. When personalizing this gun to make it my own, I replaced this component with a ventilated rubber buttpad to suit my own taste.
The trigger has a fairly heavy pull and is not adjustable, with a blade that is wide and has a good tactile feel. The safety is a transfer bar type that is situated in front of the trigger. The trigger guard is large and easily accommodates a gloved finger, which is important when this Californian native hunts winter squirrels in my current Midwestern home. This is the same trigger component found on the 2260, and the whole assembly is one piece and fabricated in high impact plastic. Admittedly this is not my favorite material on a gun, but the primary factor is how well it works, and well look at this later in performance testing.
Another major change with this gun is the high pressure air reservoir for onboard storage of compressed air. The Discovery stores air in a reservoir made of carbon steel DOM tubing, with a filling capacity of 135 cc (8.3 cubic inch). The reservoir tube is capped with a male Foster quick release connector that permits easy filling of the gun, I much prefer this set up over the filling probes used in many pcp designs. Though the recommended fill pressure is 2000 psi, the tube and valve assemblies have been hydrostatic tested to 11000 psi (the tube alone to 15000 psi). Speaking of the valve, it is a new design based on existing technology.† Additional sealing o-rings have been implemented and spring rates changed to work with not only higher air pressures but also work with CO2 pressures. The new valve is anchored in place with three screws rather than the single anchor point used with the 2260.
|The male foster fitting provides a simple filling mechanism, that is covered by a cap|
|The bolt is directly from the 2260 platfor, not the most elegeant but very serviceable.|
|The trigger is also pure 2260, I think the modders are going to like playing with this one|
|This is a very easy gun to cock and load. I like a hunting rifle that requires very little motion or effort. Last thing you want in deep cammo is flailing hands|
|The Crosman Discovery with the QB 78 PCP conversion for comparison. Both nice guns, but the compact Discovery gets my vote for an all around small game gun. Though it generates less power, it has a much higher shot capacity, less shot to shot variance, and is much quieter..|
The receiver is grooved, and the sharply cut grooving is long enough to allow short or long tubed scopes to be mounted, which makes optimal installation of the scope a cinch. I used high profile Centerpoint mounts with a Centerpoint 3-12x variable scope on my test rifle, which offered up crisp and clear images along with good low light transmission. Low light situations were further enhanced by the illuminated reticule, that was especially useful when taking the rifle on pest control duty in the evening or when inside of an unlighted barn.
The cocking action of this gun is excellent. It is the same traditional bolt action that is found on the 2260. The loading port is accessed and the action is cocked as the bolt is pulled back, after loading in the bolt is push forward and down in preparation for shooting. I found it effortless to pull the bolt back with my index finger and pushing it forward with my thumb, requiring minimal hand motion. This is a desirable attribute in a hunting rifle, and I think it is indicative of how well the hammer and valve springs are balanced that such a light hammer spring works so well.
One of the main limitations in the acceptance to pcpís in this country, is the dependence on an outside power source. These guns can be filled from either a hand pump or a high pressure compressed air tank, but both of these methods have had some drawbacks. High pressure tanks are the easiest and most effective approach to filling you pcp, however it is necessary to have a compressor (dive shop, paintball shop or fire station) in the area willing to fill your tank. Even when these facilities are available, the tanks and all the kit needed to go with them can get expensive. A hand pump on the other hand, is less expensive, more portable, and frees the shooter from reliance on a compressor. But they can take a lot of effort, which is especially true if the gun fills to the industry standard 3000 psi. That is why a gun designed to fill and operate efficiently at 2000 psi is an ideal candidate for manual filling. Take it from somebody that has charged a rifle to over 3000 psi with a hand pump, the difference between hitting the 2000 psi mark and the 3000 psi mark is the difference between day and night!
An airgun hand pump works very much like a bicycle pump, but is a much sturdier construction with a higher volume pumping chamber. The pump will also have a bleed valve to depressurize the hose after the tank has been closed, which then causes the fill valve to snap shut as the pressure in the hose falls lower than that in the guns reservoir. A braided high pressure hose is attached to the pump by screwing into a port on the body of the pump, and attached to the gun (in the case of this set up) by a female Foster coupling.
Crosman has taken an innovative step, and it is not so much the design of the pump but the packaging of it with the rifle. The discovery pump is a traditional design that can charge the rifle from empty to 2000 psi with about 100 strokes. After you fill the gun it will deliver about thirty five full power shots before needing to be charged again. It doesnít hurt to leave the gun charged up between outings; as a matter of fact it is better for the valve to be stored under pressure when not in use.
I find the pump to be solidly built and reliable, in line with other quality hand pumps Iíve used over the years. The gauge is accurate and closely matches the pressure reading obtained from the onboard gauge. One area that I think could be improved is the position of the bleed valve below the connecting hose; I find it a little awkward to reach when bleeding the line to disconnect. But this is not a critical factor and does not hamper the effectiveness of the device.
Another really interesting aspect of this gun is that it can run off of either compressed air or bulk fill CO2. The option is called the Duel Fuel option consist of an adaptor that permits the gun to be filled from a standard paintball tank, with velocities over 600 fps in .22. A single charge yields approximately 100 full power shots.
Initial Shooting Impressions
I spent a few days getting used to the gun before serious testing took place. I filled the gun with the pump a few times to get used to it, and then switched over to my tanks for the rest of the shooting.
In the couple of months Iíve had the gun, I have tested it with around thirty different pellets, and while it does have its preferences (as almost all air rifles do) it is quite tolerant and fires several brands well. In a later article I will give the specific details of the performance with a variety of pellets shot over the chrony and for groups. To illustrate my statement that this gun has everything a hunter needs withy respect to accuracy, Iíve included a couple demonstrative targets. The first target shows a series of five shot groups at 35 yards with six different pellets, the second was achieved in a sitting position with the gun rested on shooting sticks with CPs, and the last is a 36 shot group using CPs obtained with a single charge. Velocities achieved with the various pellets averaged from 790 to 850 fps, with most medium weight pellets in the mid 800 fps range. The shot to shot consistency across a fill is quite impressive
Iíve used this gun on a few squirrel hunts this season. Its compact dimensions along with performance, both in terms of power and accuracy, made this a fun little huntingrifle. It easily dropped bushytails out to 50 yards with both head shots and well placed chest shots. And the low sound signature, much quieter than even a .22 short rimfire, really opened up a lot of new hunting opportunities. On a squirrel hunt I kicked up a cottontail that ran thirty yards and held up in a dense tangle of vines, I leaned against a tree, dialed up the scope, and dumped him with a perfectly place headshot. And when I missed, it was easy to quickly cock and load the gun for a followup. I sat at the base of a tree cycling the gun for a follow up shot, and Iím sure the critter would have bolted if the gun had forced me to make to make big moves to ready for action. This is the one gun (Iím taking on my Mojave JackRabbit hunt right before the shot show. I think it will be great medicine for the big desert rabbit.
|Performance: Preliminary Results|
|Not elegant, but it works! Had to futz around to optimize lighting. The muzzle is 36" from chrony|
|Iíll write up a more detailed article on the ballistic testing later. Iíve shot several different pellets in my basement range. The pellet that produced the highest average velocity was the Beeman Laser. The upper right panel shows the average velocities for several widely available pellets as well as a couple experimental ones. The lower right panel shows a 45 shot string using JSB Exacts, the gun hits a sweet spot after a few shots and with the exception of a couple random jumps in velocity is pretty consistent. All of these shots would have enough power to reliably take small game. Each pellet had a sweet spot that was reached when the optimal pressure level was reached. I lifted 20 shot strings from longer shot strings with four different types of pellets to observe the shot to shot variance in the optimal range (left). I have a mountain of data to work through, but this is representative of my results and gives a preliminary look at the gunís performance.|
|Note: These are consecutive shots, but lifted from the "sweet spot" for each pellet type.|
|Five shot groups (left) usiing several pellets styles and weights. the gun is very tolerant and digest a number of pellets with good results
In an upcoming series of articles I will share the results from my bench test and hunting trips.
12 shots at thirty five yards sitting (right upper) braced with shooting sticks., Would have been a dead bunny everytime
37 shots from a single fill (lower right). That's a high shot count and good consistency from a 2000 psi fill!
Click on this link and you'll go to a page that shows the action removed from the stock. The gun is too rare a commodity for me to start ripping down further at this time. Once I've got a couple of upcoming hunts out west cleared, I'm going in!
|The Discovery is a light and compact rifle that I find a pleasure backing around on a day in the woods or bunderbashing in the desert. Light and unobrtusive, the gun can be brought quickly into play. This handeling is further enhanced by the light cocking effory.
I use two methods of charging my tanks, a carbon fiber 17 cu ft 4500 psi nd the pump pakaged with the gun. Takes bout 120 pumps to get the gun fully charged
|Taking the Discovery Hunting|
|Based on a couple of months of intensive use, I believe the Benji Discovery to be an excellent option for small game such as rabbit and squirrel. It is light and compact, easy to cock and load, it is accurate and powerful, and with the high shot capacity a single charge will keep you in the field for a full day of small game hunting. I took both rabbits and squirrels out to fifty yards, and consistently achieved one shot kills.
The other part of this hunting rig I really liked was the Centerpoint scope with illuminated reticle. I found that the excellent light transmission combined with the glowing crosshairs were an asset in the low ambient light conditions encountered during early dawn and evening hunts.
|Mojave Rabbit Hunt|
|I flew into Las Vegas for the SHOT Show, arriving a few days early so I could get in a rabbit hunt. My plan was to hit the open desert during the day to chase up some jackrabbits, then drive down to the thick brush along the washes bordering a desert golf course in pursuit of cottontails at dusk. The Discovery was a pleasure to carry, it is light weight and compact and after a single charge was ready for a full day of hunting. It turned out to be a hard hunt, the desert had received a lot of rain during the season and the brush was heavier than I'd ever seen it. The rabbits were well covered and holding tight, so I ended up walking long distances glassing the area looking for signs of rabbits tucked away under the brush.|
|The Discovery comes easily and quickly to shoulder, and I found that I could shoot it well from any position.|
|I took a couple of big jackrabbits the first morning out, at 35 and 50 yards respectively. Using a JSB Exact pellets, the gun yielded up power and accuracy that was capable of dropping these big desert hares cleanly. The following morning I was able to bag a couple more.|
|At dusk I walked along a dirt road where the cottontails would cross to get to the golf course to feed. I hid behind the scattered brush and ambushed them as they headed for the grass.|
|All in all I found this a great little rifle to travel with. The pump disassembled for easy packing and fit into my duffle bag. I appreciated the fact that I didn't have to pump the gun over 2000 psi to get the performance required for hunting. And I got two days of hunting in from that single charge, plus a bit of plinking to empty it before packing it away fro the trip home.|
So if I turn a critical eye on the gun? As mentioned the plastic trigger is not my favorite aspect of the gun, but it is function that matters. The trigger provides a good tactile feedback with minimal creep and the trigger breaks crisply. I personally am happy with this trigger, it is not target quality but provides a good solid performance for a hunting rifle. I believe this will probably be the opinion of most shooters, but there are those that will want to tweak and tune it. The trigger as specified is non-adjustable, but there are a lot of online resources that will teach the aspiring gunsmith to smooth out the action, though youíll void the warranty doing so. I think that this is an area where weíll see third party suppliers offering aftermarket parts; perhaps even the Crosman Custom shop will pick up on it.
Iíve put several hundreds of pellets through the Discovery to date, and it is robust and reliable. The gun carries and comes to the shoulder well, and will fit most shooters, though if you have long arms it wouldnít hurt to replace the buttpad. It has a very ergonomic cocking action that is really quite nice in a hunting rifle. Easy to cock and load without a lot of motion. The Benjamin Discovery will be an important gun for the domestic market; offering very good performance in a price effective package. Put this in perspective; you will get a gun capable of generating over 17 fpe and placing a .22 pellet in a quarter inch group at 35 yards, with a quality hand pump, that also runs on bulk fill CO2 (optional adaptor required) for under $400.00 ÖÖ alright, just under at $399.00! This will open the world of PCP airguns to a whole new audience, which will only benefit the sport as a whole. I really think Crosman got it right with the Benjamin Discovery.
|I have restocked my Discovery with a C1 style stock, which is characterized by a straight wrist typical of an English shotgun. This gun is small and compact, lightweight, and it comes to the shoulder very quickly. I find it one of the most shootable guns in my collection, and it is one that I feel comfortable shooting offhand from any position. On this trip I took it out on a cold, snowy winters day in Indiana in pursuit of fox squirrel. Wearing snow camo I was able to hunker down by a den tree and wait for the squirrels to come out and go un-noticed. The sequence below shows a squirrel dropping from a head shot, a .22 pellet hitting at 55 yards.|