I am now getting back to the Beeman Dual Cal article series after that short diversion on spring vs gas rams, etc. The reason for the short detour was another Beeman rifle that defied the odds. While having remained cocked in storage for over a year, it still shot just like the day it was put away. But, let’s move on.
.177 Barrel Installed, what can it do.
I setup at the bench with a sampling of 6 top pellets; to see what I would get from our Beeman Dual Cal setup as a .177. Here are the pellets that I’ll be using for this test:
- Meisterkugeln – Match Grade Wadcutters 8.3 grain – Average Velocity – 960 FPS – See Shot Card
- RWS Super Dome – Domed hunting pellet 8.3 grain – Average Velocity – 921 FPS – See Shot Card
- JSB 8.4s – Domed Match pellet 8.4 grains – Average Velocity – 840 FPS – See Shot Card
- Crosman Premier Hollow Points – Hollow pointed hunting pellet 7.9 grains – Average Velocity – 930 FPS – See Shot Card
- Vortex Supreme – Domed hunting pellet 8.64 grains – Average Velocity – 834 FPS – See Shot Card
- H&N Baracuda Match – Heavy domed hunting pellet 10.65 grains – Average Velocity 785 – See Shot Card
When you look at the above selection and their related numbers, you can’t help but wonder what exactly is going on. Surely 8.3 grain pellets should all shoot about the same velocity. How do you get a spread of over 110 FPS between pellets? This is actually a good place to spend a bit of time.
Trial and error is the only solution.
It may be hard to except, but trial and error may be the only answer. Each airgun’s barrel is unique and may prefer one pellet over another. Each pellet manufacturer has its own “blend” of lead, which may increase or decrease the velocity out of the barrel. Finding what’s best for accuracy out of your particular airgun is going to only happen after you’ve done your own tests. I can certainly give you some things to look for however.
- Buy quality pellets. Commodity pellets, like the ones you find on the big box store shelves, are going to vary. One tin may be great, another may not be. If you notice a difference in pressure when installing the pellet into the breach, then you’ve got a batch of pellets that has varying head sizes; and that means varying velocity and most likely poor accuracy. Higher grade pellets are generally much more consistent.
- Be more concerned about accuracy that velocity. The only way you will really know what your airgun is doing is with a chronograph. If you are serious about airguns, you will need to get one. Once you have a chronograph, look for the most consistent pellet regarding velocity, NOT the fastest pellet. That is a good step towards consistent accuracy.
- See rule number 2
How did our accuracy tests turn out?
Here is the target from our tests. I shot 5 pellets, 6 with the Crosman Premier Hollow Points because I thought I may have pulled the last shot, at each target. I then used OnTarget’s Target Data System to compile the numbers for each group.
The best pellet turned out to be the RWS Superdomes, which had a spread of .360″ center to center. The next best was the JSB 8.4 grain diabolo pellets, with a spread of .659″ center to center. The rest of the groups were really all over.
You’ll find links to the PDFs of each shot group that you can download listed with the pellets above. This is a great feature of the software that I’m using.
Bench talk before we move on
On thing about the Beeman Dual cal’s trigger, while it has an “OK” trigger, it proved problematic from the bench. There is definitely something, like a bur or other debris, in the trigger group that’s causing it to feel rough. This is less noticeable when shooting from the shoulder. It requires that I use more “grip” than I would like when bench shooting; which can throw off the dynamics of a proper artillery hold.
I am going to swap barrels now and run the same type of test, this time in .22 caliber. I’ll be very curious to see which barrel delivers the better accuracy. If theirs is a real standout in either caliber, I may swap out the scope for something better, and run some tests at 20 yards. So definitely keep an eye on the blog to see how thing unfold!