Tuning up an older airgun
by Tom Gaylord
Writing as B.B. Pelletier
This report covers:
- Lots of new airgunners
- Time for the basics
- Back to today
- A joke
- What’s up with the Gamo?
- The solution
- Tune in a Tube
- Alternate method
- Did it work?
One of the guys in my church asked me what to do about a scope that had gone bad on his Gamo rifle. He told me the reticle had tipped sideways inside the tube. After some discussion I learned that the scope had come bundled with the Gamo Whisper he had, and that told me most of what I needed to know. It was a bundled scope which means cheap. And it broke. I told him I had lots of extra scopes and I’d give him one — a better one than he had. But all that is for tomorrow’s report, so I’ll stop here,
Lots of new airgunners
Before I continue I was told by Pyramyd Air last week that they have bunches of brand new airgunners who have come on board only recently. I know why this is and therefore I know who these new airgunners are. They are firearms shooters who are having difficulty finding ammunition to shoot. That is one reason I started the “How to reload” report series. But not everybody wants to reload. For various reasons, many shooters just want to shoot and if they can’t get ammo for their firearms they turn to airguns. In their minds it’s better to shoot with something than to do nothing. I can understand that!
Time for the basics
With all these new airgunners, Pyramyd Air has asked me if I can write some reports about the basics again. Now, you long-time readers know that I have written volumes about the basics over the 17+ years this blog has been published. But what has happened is in recent times I have been concentrating on the 300 or so readers who regularly comment on the blog and I’ve unintentionally disregarded the 100,000+ registered readers and the who-knows-how-many unregistered readers we have. So I agreed to write about the basics each week, and tomorrow I’m going to start a report on how to mount a scope. Believe me — the firearms guys know a lot less than you airgunners about that subject! Not one in fifty AR-15 owners has a clue what barrel droop is, even though the AR-15 is the barrel-drooping queen of the firearms world.
Back to today
So my friend gave me his obsolete Gamo Whisper to mount his new scope. The rifle is the older Whisper that came with a coiled steel mainspring. It’s no longer offered that way but it’s still a nice air rifle. When he gave it to me we had a second longer conversation about his problem with it. It wasn’t holding zero! Well, that told me everything I needed to know, so I got to work and tomorrow you will see the result.
However — and this is a big “however” — when I shot his rifle I noticed that it buzzed like a bottle of honeybees! The buzz came at the end of the shot cycle and that told me what was happening. I will give you a little time to figure it out and then we will talk again.
This is to take up space while you are working out the problem with the Gamo Whisper.
“An exercise for people who are out of shape: Begin with a five-pound potato bag in each hand. Extend your arms straight out from your sides, hold them there for a full minute, and then relax. After a few weeks, move up to ten-pound potato bags. Then try 50-pound potato bags, and eventually try to get to where you can lift a 100-pound potato bag in each hand and hold your arms straight for more than a full minute. Once you feel confident at that level, put a potato in each bag.”
Ba-dump bump! (snare drum roll and rim shot, followed by a cymbal crash)
What’s up with the Gamo?
Why does my friend’s Gamo Whisper buzz so much? Well, the buzzing is caused by vibration. And what is causing the vibration? It can be one of two things. Either the parts in the Gamo powerplant have too much room or the mainspring has canted at one or both ends. It could even be both things. The question is — how do we solve the problem?
The best solution is to get rid of all the slop between the parts — just as I did when I tuned Johnny Hill’s RWS 45 springer. I used button bearings on the piston to suspend and quiet it, and I also used a super-tight spring guide to quiet the mainspring.
All well and good. But what if you don’t want to go inside the powerplant of the gun? What if you want an 85 percent solution with very little effort? Can you say Tune in a Tube (TIAT)?
Tune in a Tube
Back when I tuned Johnny Hill’s Diana 45 in 2015, I used black tar on the mainspring to quiet it completely. Black tar is a thick viscous grease that’s officially known as open gear lubricant. It sticks to the coils of mainsprings and doesn’t allow them to vibrate by stopping their movement. TIAT works just as well or better than black tar and doesn’t take as much velocity away from the airgun.
How it’s done
To get TIAT into the rifle’s powerplant you can do one of several things. The easiest and most precise way is to use a grease gun that has a small injector needle at the end of a flexible hose.
Or you can just use the TIAT applicator, which is also a long thin needle that’s designed to do the same thing. It works well, but the applicator can’t be conveniently refilled. In the past 4 years I have used about 9 ounces of the TIAT grease to fix about 100 airguns, if that gives you any idea of how much I use.
Okay, you don’t have a grease gun to dedicate to TIAT. What else can you do? Get a small thin-bladed screwdriver to spread the grease deep inside the mainspring that is visible through the cocking slot. You have to remove the barreled action from the stock to do this.
This Gamo rifle is held together with Torx screws. I have a tool from Harbor Freight that has a cassette of Torx drivers and the number T 15 bit fits the Whisper screws.
Once the action is out the mainspring can easily be seen and accessed. Spread TIAT inside the powerplant, everywhere you can reach.
I was pleased to see blue Locktite 242 on the threads of all the stock screws. I believe the factory put it there to keep the screws from backing out during firing.
Did it work?
The proof of the pudding is in the eating, or in this case the shooting. The first shot was slightly calmer, and by shot 20 the rifle was very calm. It’s not as good as it can get, but I never took the action apart and only spent a few minutes applying the grease. I’ve decided not to tell the rifle’s owner and see if he realizes what has been done. If he does and says something about it I will be pleased.
This report was a freebie I got from mounting a scope on my friend’s air rifle. Tomorrow I will show you the second half.