There’s normal gun maintenance and then there’s gun “tuning.” Back in “the day,” enthusiast airgunners not yet baptized into the PCP world would spend a lot of time and energy creating the perfect spring gun, i.e. breakbarrel, sidelever, and underlever, experience. Much of that world has been supplanted by affordable PCPs and gas rams. Does tuning a spring gun even have a place for today’s shooter? Of course it does. Just because it’s becoming a lost art doesn’t mean that it’s not a great part of the hobby. Let’s take a look at how it fits with today’s airguns and what you’ll need to get started should you want to give it a try.
Understanding the Anatomy of a Spring Airgun
We’ve already discussed the anatomy of a spring airgun in this article. Let’s do a short recap. Spring airguns use some sort of mechanism, i.e. spring, gas ram, etc., to propel a piston through the compression chamber, generating enough pressure to drive the pellet down range.
By design, a gas ram will “feel” better than a traditional spring gun due to the lack of rotational torque and harmonics found in most metal springs. Proper engineering can overcome these obstacles, but it’s way cheaper and easier to drop in a gas ram than to engineer a metal spring, chamber, piston, etc., to all work perfectly together.
Why Spring Piston Tuning has Become Less Popular
A lot of manufacturers chose to drop in gas rams vs. fix their engineering. This makes sense, as you get the same power but without the buzz and rotational torque. Spring guns are already tough to shoot given dual recoil. When you introduce a “normal” metal spring, you add a third recoil to manage as the rifle will want to twist in the opposite direction of the spring’s rotation. Gas rams reduce felt vibration and completely eliminate the rotational torque, gas rams are not perfect and certainly don’t fix poorly engineered spring guns. In many ways, tuning a traditional metal spring gun will deliver a better shooting experience than just dropping in a gas ram, and that’s expressly why folks did it, and may start doing it again.
The Advantages of a Traditional Metal Spring Over a Gas Ram
The beauty of a metal spring is that there’s no “air” to leak out. We can’t begin to count the number of gas ram guns that just went flat sitting on the shelf. And when they go flat you have to replace the ram, as all but a few are able to be rebuilt. On the other hand, springs do wear out eventually but they are cheap to acquire and easy to replace. And, per the point of this article, you can tune them to really improve consistency and the overall shooting experience.
Things You Can Tune on a Traditional Spring Airgun.
Let’s take the old-school RWS 350. It’s a monster powerhouse of a German-engineered and manufactured beast of a magnum spring airgun. It’s already pretty amazing right out of the box, but it does have a decent amount of buzz and vibration that can be tuned out of it.
The first thing you’ll need to do is build or acquire a device called a spring compressor. The springs are held in the receiver under pressure. If you start driving out pins without first securing the end cap, you are likely to get injured, so DON’T DO IT without proper equipment and safety precautions.
Assuming you have the knowledge and gear to teardown, tune, and rebuild, here are the things to look for.
Lubrication – Most spring guns come loaded with tool oil. It’s very light and does nothing to prevent vibration or unwanted harmonics. So a proper lubricant like the Air Venturi Tune-In-A-Tube will make a huge difference. It’s like wrapping rubber bands around a bell. The bands prevent the metal from vibrating when the striker hits the bell and you just get a “thwack” vs. a long reverberating bell sound. The Tune-In-A-Tube Grease “wraps” the spring and is very sticky. Using it will probably drop a few FPS from your velocity, but you’ll have a more consistent shot curve and almost no vibration. It’s crazy how much just that one fix will do for a standard spring gun.
Check your spring ends – While you’ve got the spring out, you’ll want to check the ends. Oftentimes they are not finished properly and have sharp edges. When the spring is being compressed, these ends rotate and the sharp edges will catch inside the action and can make the rifle more difficult to cock or increase the rotational torque when fired. Regardless, cleaning up these ends so that they are smooth and won’t catch during cocking and firing, can make a big difference.
Process the piston and compression chamber – Most pistons are smooth which can make the lubrication less efficient. Removing the piston, cleaning and cross hatching the inside and outside can allow the lubricant to work better, reducing felt recoil and vibration. We lock the piston in a lathe and use a scotchbrite pad to clean and cross hatch the piston.
Processing the compression chamber can be a bit more challenging as our lathe is not big enough. So, we’ve used rods fitted with scotchbrite pads and then attached to a cordless drill which seems to get the job done well enough.
Replace the seal – while you’ve got it all out on the table, it’s a decent idea to go ahead and replace the piston seal with a new or upgraded seal for optimal or even improved performance. There are third parties that have tailored their entire businesses to providing “better than OEM” parts for these airguns. One of our favorite suppliers is Vortek Products. They carry complete rebuild kits for many traditional airguns.
The End Result
Once you’ve processed all the parts, applied the Tune-In-A-Tube, installed a new seal, and reassembled your airgun, it’s time to “feel” the difference. If you’ve done it right, then the transformation will be like night and day. Most magnum springers go from a vibrating, buzzy, mess to a wonderfully tame and satisfying “thud.” It’s really amazing what a couple of hours of bench time will do for you. One last HUGE benefit to a full tune like this is that the Tune-In-A-Tube lubricant essentially lasts forever. Once you’ve put in the time, your gun should be good for many years of high-volume shooting.
Need Help?
We don’t currently offer tuning services, but we do carry some of the gear you’ll need. We have our rail lock spring compressor and Tune-In-A-Tube lubricant. We recommend outlets like Gateway to Airguns, Airgun Nation, and Vortek Products as resources that can help you in your spring airgun tuning journey. Remember to have fun and be safe.
