.22-caliber Lightweight Disco Double: Part 4
by Tom Gaylord, a.k.a. B.B. Pelletier
Today, we’ll look at the accuracy of the Disco Double. Before that, however, I mounted a scope, a TKO airgun silencer that they call a muzzlebrake or a lead dust collector, and something I’ve never seen in print before but something I’ve used on many precharged air rifles over the years — a bolt keeper!
What’s a bolt keeper?
First, let me tell you that when I mounted the TKO silencer, it fit the barrel perfectly. There were no barrel alignment issues that I was warned about, and I checked closely. This unit is very well made and looks beautiful on the gun. The unit I’m testing is 8-1/4 inches long; and, yes, Lloyd, I checked that it indeed is a .22 caliber before mounting it. However, when the silencer is on, the top end cap does not fit.
When I shot the gun with it on the first time, I have to say I was underwhelmed. It was quite loud. A second shot confirmed this. Then, I held the rifle to my shoulder and fired a third shot. That’s when it hit me — a blast of air in the face not unlike the glaucoma test eye doctors do. The bolt was opening and discharging compressed air with each shot!
This happens a lot with precharged guns and it doesn’t matter how cheap or expensive they are. The bolt handle lifts up and air comes back through the action. On the lightweight Disco Double, it only begins to happen when the rifle is at the bottom of the power curve, which is where it was when I tested it this time.
A simple fix is to fasten a rubber band around the bolt handle to hold it closed during the shot — a bolt keeper. Once on the gun, I just leave it there. Even though it’s not needed until the end of the power curve on this rifle, I don’t want to worry about it. You can cock and load the rifle with the band in place.
With the handle held closed in this fashion, the rifle suddenly became very quiet — as in Benjamin Marauder quiet! I now understand why shooters have been so excited about this unit. It really works!
NOTE: Due to several reader questions about this silencer, I am removing it from the rifle and returning it to Lloyd. Silencers are a very touchy subject, since owning one that will function on a firearm requires a license for each specific silencer. I don’t want to mislead any reader, so in the interest of clarity I am simply not going to use or possess this item any longer. I wrote an article on silencers that can be accessed here. If you have any questions on the subject, I recommend you read that article.
The rifle now weighs 6 lbs., 11 oz. with everything installed. That’s very light for a serious air rifle.
I mounted a UTG True Hunter 3-9X40 scope on the rifle. Since UTG packs rings with this scope, I used them, but they’re Weaver-style mounts. So, I had to use a UTG Weaver to 11mm dovetail adapter to make them fit the dovetails on the rifle’s receiver.
I’ll be shooting from a rest at 25 yards today. The range is indoors, so wind is not an issue.
Sight-in was accomplished with .22-caliber Crosman Premiers; so after I was on the paper, I shot the first group of 10 shots at 25 yards. The hole they made is a little taller than it is wide, but it measures 0.569 inches between centers. While that’s okay for 25 yards, it isn’t great. I’d like to see something a couple tenths smaller.
Next up were Beeman Kodiak pellets. They’re identical to the .22-caliber H&N Baracuda pellets that Lloyd tested the rifle with, and they were what I had available. They put 10 into 0.655 inches between centers. Like the Premiers, that’s not bad…but not as good as I’d hoped.
Beeman Kodiaks opened up more, to 0.655 inches between centers. Only use them if you need a heavy pellet.
JSB Exact RS
I followed the Kodiaks with some JSB Exact Jumbo RS pellets. They’re even lighter than the Crosman Premiers, and sometimes they can be very accurate in precharged rifles. This was one of those times. Ten pellets went into 0.365 inches, which is exactly what I’d hoped for the Disco Double. This is the pellet for this rifle!
Nex, I tried the RWS Superdome pellet that’s always recommended. I don’t often have good luck with them, but a lot of shooters do. I stopped after just 4 shots, though, and you can tell from the lateral spread that measures 0.634 inches between centers that they weren’t going to perform.
JSB Exact Jumbo
The last pellet I tested was the JSB Exact Jumbo. These are usually among the top pellets in .22-caliber precharged air rifles, so I felt they deserved a chance. The first 2 shots were on a fresh 2,000 psi fill, and I’m not sure the rifle wasn’t overfilled by a slight amount because they both landed away from the main group. Shot 9, however, was shot while the rifle was grouping well, and I have no idea why it’s above the main group. The 10-shot group measures 0.647 inches between centers, making this the second-best pellet I tested in the rifle.
These 10 JSB Exact Jumbos measure 0.647 inches between centers. The first 2 shots are the holes at the right and bottom right of the main group. Then, the rest of the pellets went into the big group, except for shot 9 that went high. There is no explanation for that one. This is a pellet I would keep trying.
Filling from a hand pump
The biggest feature of the Benjamin Discovery, aside from the low price, is the fact that the maximum fill pressure is just 2,000 psi. It’s full right where other PCPs have run out of air. And that makes the Discovery extremely easy to fill with a hand pump.
Using the Discovery factory pump, I began the fill at just under 1,000 psi and pumped until the onboard pressure gauge read 2,000. It took exactly 100 pump strokes to fill the gun; and, until the final 20, they were as easy as inflating a bicycle tire. Only when the pressure passed 1,800 psi did I notice an increase in pump handle resistance.
One tip when filling with a hand pump is to go slow. Allow time at the top and bottom of each pump stroke for the air to flow through the various stages inside. If you don’t, you just waste energy and heat up the pump unnecessarily.
Observations so far
So far, I’m thrilled by the performance of the Lightweight Disco Double. The number of shots I get on a fill is large enough for serious shooting before it’s time for a refill and the rifle’s performance leaves nothing to be desired. A glance at the onboard gauge needle, and I know the status of the fill.
When I tested the original Benjamin Discovery rifles in both calibers, the guns I used were pre-production prototypes. I shot groups under 0.6 inches with both calibers; but at that time, I was shooting only 5-shot groups. The JSB Exact RS pellet did not exist at the time of that test. So, it’ll be interesting to see what this rifle can do at 50 yards with 10 shots. Remember — this is the first Benjamin Discovery production rifle I’ve ever shot!