Testing the Gamo Whisper – Part 7 Gas spring conversion!
by B.B. Pelletier
Pinks are going fast!
Crosman’s pink 760 has turned out to be a hit this season. Pyramyd has had to reorder several times, and they have now received what will probably be their final shipment before the end of the year. If you want one of these outrageous Barbie-doll-pink air rifles, the time to act is NOW!
Today’s report is my huge surprise about the Gamo Whisper. It took longer than I thought to get to this report, but today you’re going to read about an exciting new conversion possibility for this rifle: a gas spring for the Gamo Whisper! Please hear me out all the way, because there are some ramifications almost nobody knows about.
Ramification No. 1: There’s already such a conversion on the market. But the one I’m testing will be considerably more affordable. For those of you who weren’t aware that there was a gas spring conversion for the Whisper – happy day! I’ll reveal the other ramifications as the story unfolds.
What IS a gas spring?
A gas spring is a sealed, unitized device that replaces the coiled steel mainspring and piston in a spring-piston airgun. The gas spring unit uses compressed gas to power the piston. You’re more used to gas springs than you may know, because they are all around you. They hold up the back deck lid on your SUV or minivan, and they make your desk chair adjustable for height. Gas springs have replaced coiled steel for a lot of applications where the spring has to last for years in a fully compressed state. Get it? You can leave your gas-spring-equipped air rifle cocked for hours and even days without degradation of power. Heck, your office chair stays compressed for years and still works – and the gas spring unit that’s in an airgun is quite a bit more robust than the one in a chair.
How do gas springs differ from gas rams and gas struts?
They are the same thing. Gas spring is the correct generic term and “struts” or “rams” are slang terms, but they all refer to exactly the same thing. Instead of a coiled steel spring to push the piston forward, a gas spring uses compressed gas to do it. The gas remains captive inside the sealed unit, so you don’t lose it as the gun is shot.
How does the Whisper like its gas spring?
I pushed for this conversion because of the Whisper’s built-in silencer. I figured a gas spring would cancel all powerplant vibrations, giving the silencer a chance to work. Well, it does cancel all vibrations, but the powerplant noise sounds the same. So this conversion does nothing to quiet the rifle.
HOWEVER, that’s where the bad news ends. The Whisper with a gas spring is a transformed air rifle! It’s so dead-calm that most shooters will not believe it! In fact, although I have owned numerous gas-spring air rifles, I still have a hard time believing how absolutely smooth this one is. Now that I’ve installed the GRT III trigger, this particular rifle is positively marvelous! If it turns out to be accurate, as well, I might have to add it to my growing collection (hint to wife). Given the accuracy of the other Whisper, there’s a good chance of it.
The cocking stroke changes
All gas-spring rifles have a noticeably different feel than steel-spring rifles when they’re cocked. Instead of a little slack after the barrel breaks open, then a slow build to the maximum effort around three-quarters of the cocking stroke, you’ll feel the full resistance from the start with a gas-spring rifle. It feels like it never changes throughout the stroke, though it really is a few pounds lighter in the beginning. Compared to cocking a rifle with a steel mainspring it feels like a lot more effort until you get used to the difference. If you recall, the cocking effort of the first Whisper I tested with the steel mainspring was 35 lbs. With the gas spring conversion, the effort is 34 lbs. But honestly – it does feel like more.
When the gun fires, there’s a solid thump like a bank vault closing. There’s no vibration. And, the firing cycle seems quicker than with the steel spring, though that may be due to the abrupt end of the cycle. Once that piston stops moving, everything goes dead. Recoil is greatly reduced with the gas spring installed, and that’s something not common to all gas springs. Recoil is a function of piston weight, and this conversion uses a lightweight piston so there’s very little felt recoil. That should help with accuracy, and we’ll test for it.
This is a comparison test between the gas spring and a Gamo factory steel spring. The table below gives the velocity and extreme spread for each pellet with the steel spring and then with the gas spring. I retested the steel spring gun because I had only tested a couple of pellets before. Because two different rifles are involved, you don’t see a direct comparison of before and after the gas spring is installed.
Crosman Premier 7.9 grain
So, the gas spring is slightly more powerful in the two rifles I happened to test. That was never the plan; it simply turned out that way this time. The smooth shooting behavior is worth accepting a power REDUCTION, so to have MORE is gravy. I think that if the gas spring produced similar results to the steel spring, it would be well worth the cost.
And what IS the cost?
As I write this report, Pyramyd Air is working that out. They know what the unit costs them but not how long it takes a technician to install and test it. I was eager to get this first report posted, so I jumped ahead of the business end of the process. There isn’t even a web page to send you to yet, but I will give it to you as soon as I can.
New guns, first
The initial supply of gas springs is quite limited, so Pyramyd will install them in brand new rifles first. Those rifles will be sold as complete guns. When they get the price calculated, I’ll alert you. Those guns will probably vanish in days, but there will be more gas springs to come. As soon as the gas spring maker ramps up his production to the level that Pyramyd Air can always have a few in stock, they’ll start offering to convert their customers’ rifles. I would guess that will happen after January, if the manufacturer can meet the demand for new guns. At this time, Pyramyd Air has no plans to sell just the gas spring by itself, because the installation requires a technical knowledge of the rifle and gas spring.
The benefits of gas springs
Gas springs act quicker, which some shooters feel helps with accuracy. Maybe it makes them less hold-sensitive (but it doesn’t cancel it altogether). Gas springs can be left cocked for hours without losing energy. This is a real plus for hunters. This particular gas spring unit has the surface of its internal moving parts finished to 4 microns, an incredibly smooth finish. That will help maintain the gas seal for a long time. Gas springs often reduce the weight of a rifle, though in the Whisper’s case, they do not. The weight remains the same. Gas springs reduce felt recoil. Gas springs shoot with unbelievable smoothness. I cannot emphasize this benefit enough. If I were to let you shoot both guns together, you would want the one with the gas spring.
Chew on this over the weekend. Gamo has been standardizing their powerplants over the past few years so that today they produce only a couple of different-sized pistons. The Whisper powerplant is the same size as the Gamo CF-X, etc. How does that strike you? Perhaps like the SECOND ramification!