Now that all the “hard” work is done, it’s time to get our Discovery ready to take out into the field and see what she can do. But before we just head out into the desert and start pulling the trigger, we need to get an idea of what pellet we want to focus on, what will be our optimal shot count, and what kind of variance we are getting across those shots.
Like our old high schools, PCPs grade on a curve…
The only way to get really consistent shots from a PCP airgun is to install a regulator. A regulator will measure out the exact same pressure of air for each shot (theoretically), delivering a consistent velocity for each shot. The Benjamin Discovery does NOT have a regulator from the factory, so you are relying on a balance between the hammer spring and the valve spring to deliver a number of useable, relatively consistent shots.
Our test rifle can shoot about 30 +/- shots from 2000 psi down to 1000 psi. Around shot 20, the velocity starts dropping like a rock. But, from shots 1 to 20, things are very, very consistent. Again, using our Benjamin Discovery Hollow Points, shot 1 started at around 810 fps and shot 20 ended at 811 fps. The maximum velocity was 832 FPS. That gives us an extreme spread of only 22 FPS. That’s pretty darn good from an unregulated, entry level PCP airgun. In fact, I’ve tested some PCPs costing a whole lot more that don’t deliver that kind of consistency.
Final steps before basic accuracy testing…
Before I start testing for the “best” pellet and basic accuracy, I really need to clean the barrel. Unfortunately the Discovery does not lend itself to clean from the breach, so we’ll have to go from the muzzle. You could dismantle the rifle, but you’d run the risk of voiding your warranty and damaging some of the small interconnecting parts.
I’m going to start with a nylon brush and just see what kind of progress we can make with that. It took a bit of time and a lot of patches, but eventually they started to get a bit cleaner and then eventually pretty close to completely clean. Expect to spend 20 minutes or more just getting the bore cleaned out. It’s well worth the time to clean and maintain your airgun. Doing so means that you’ll get the best performance and if you do it regularly, it should be performance you can count on.
Picking the pellet contenders…
I have over 70 different varieties of .22 cal pellets that I’ve collected over the years of testing. You can bet that at least one or two is going to be accurate in just about anything that come across my bench. When it comes to the Discovery, you can almost go up to the shelf blind folded, grab any tin and know that you’re going to get halfway decent accuracy. I selected 6 different pellets for my initial tests:
1 – Discovery Hollow Points -14.3 Grain – .269″ CTC
2 – H&N Field Target Trophy – 14.66 Grain – .298″ CTC
3 – Crosman Premier in the cardboard box – 14.3 Grain .337″ CTC
4 – JSB Metal Mags – 17 Grains – .488″ CTC
5 – H&N Baracuda Match – 21.14 Grains – .418″ CTC
6 – H&N Baracuda Hunter Extreme – .451″ CTC
The extreme variance between all these groups was only .219″ CTC. Granted I was only shooting at 10 yards and only using a 4×32 scope. I have to wonder if the larger groups were about the inherent accuracy of the rifle or just me? Tim will certainly tell. In any case, let me share with you what those results tell me.
What did we learn?
Up close, the Benjamin Discovery Hollow points are going to be pretty hard to beat. When you start to stretch things out to 40 and 50 yards however, they may start to wander as the hollow point starts to work against them. I believe we’ll see the Premier’s in the cardboard box or the H&N Field Target Trophy pellets more accurate at range. The “dark horse” pellet in the bunch is going to be the H&N Baracuda Match. If that pellet has enough initial velocity, it may hold a tighter patter at range because of the increased mass of the pellet.
Of course there’s only one way to find all this out and that means we’re heading out to the desert for some more testing. So keep your eyes on the blog for our last article in this series on the Benjamin Discovery. But, don’t think we’re completely done. If I have my way, we’ll start working in some of the wonderful customizations that are out there for the Discovery. Not only is it a great gun out of the box, but there’s almost no end to what you can get to customize it to your perfect needs. It’s a great airgun!