By Tom Gaylord
Writing as B.B. Pelletier

This report covers:

  • Computer crash
  • More power
  • Is all the power still there?
  • Breech seals
  • Transfer ports
  • Air transfer port test
  • I could go on!
  • Today’s point

Computer crash

My main computer died suddenly Monday morning, so I had to scramble to get a new one and have the old data transferred. I’m working on Edith’s computer that has the same software but is set up differently in the user interfaces. So things have been a struggle this week. One big problem is transferring photos and videos from cameras. I can do it, but it takes 4 times as long.

More power

I was hoping to do the Teach me to shoot report on holding a 1911 pistol today, but the computer issue made that impossible. So I’m going to address a topic that seems to be coming up a lot these days — getting more power from an airgun. You know, comedian Tim Allen built his career around the premise that men always want more power from everything. And he took that to the extremes — showing just how ridiculous it can become. Like an episode on his television show, Tool Time, where he got into racing garden tractors with V8 engines installed. Like the Boss Hoss motorcycle, they are something to see, but you wouldn’t want to ride one very far!

And I received a request for how to increase power in a Daisy Red Ryder yesterday. The Red Ryder has a BB gun mechanism — not a regular spring-piston powerplant, and as such is not conducive to power increases.

Is all the power still there?

Oddly, I had a dream the night before writing this report. I was in England with my Beeman R1 rifle and the authorities were about to check its power. But I had secretly removed the breech seal and that turned a 19 foot-pound gun into one that only has 5 foot-pounds. Maybe I thought of this because my Webley Mark II Service breech seal leaks badly and needs replacing. In my dream it worked, but would it work in real life? Is a breech seal really that important?

Breech seals

Yes, breech seals are very important to the power of most airguns, but I don’t know that missing one would chop the power by that much (19 foot-pounds to 5 foot-pounds). Don’t even think it would cut it in half!

HW35 breech seal old
This HW 35 breech seal (arrow) is old and worn flat. It is losing air and velocity.

HW35 breech seal new
A new breech seal added an average of 26 f.p.s. to the rifle, plus tightened the spread.

Transfer ports

There is something similar that I do know, however, because it actually happened to me. When my new Whiscombe rifle arrived I was excited to see how powerful it was, so, like every airgunner I know, I shot it across a chronograph. With the .22 caliber barrel installed I was getting under 6 foot-pounds! I was devastated! How could this be? I had paid a bundle of money to get the mostest-powerfulest spring airgun on the planet. Did they send me one made for the UK market that was permanently hamstrung for their power laws?

I called Rodney Boyce, the U.S.-based agent through whom I purchased the rifle. He laughed when I told him what I’d found. He told me that whenever Whiscombe shipped a rifle out of the UK, even though it was an FAC (Firearm Certificate) power rifle, the Home Office wanted it to leave the country restricted in power. So he installed an air transfer port limiter, which was an Allen screw with a hole in the center. He had included a package of them with my rifle so I could experiment with different power levels. All I had to do was remove the limiter with the wrench he provided and the rifle would return to full power.

Whiscombe transfer
The air transfer port in this Whiscombe JW75 has a limiter installed. An Allen wrench removes it.

Whiscombe transfer limiters
Whiscombe sent a range of air transfer port limiters, plus a couple screws that I could drill out myself.

When I removed the limiter, the rifle jumped from under 6 foot-pounds to over 26 foot-pounds in .22 caliber, using the same pellets. In .25 caliber it got over 32 foot-pounds. So air transfer ports do make a huge difference in power. But you can’t just open them up as large as you want!

Air transfer port test

Tim the Toolman Taylor (More Power!) would have drilled out the air transfer port until the piston popped out. His approach was always to make it bigger, stronger and more powerful. Unfortunately, that doesn’t always work.

When I wrote the Beeman R1 book, I did a test of air transfer ports that was included in the custom tune chapter. Dennis Quackenbush made me a special R1 spring tube with interchangeable transfer ports and I tested them to find out what worked. My test wasn’t exhaustive, but it did prove that the transfer port size 0.125-inches that is already in the R1 is the optimum size for both .22 and .177 calibers.

R1 transfer port
This R1 transfer port can be changed quickly. Made by Dennis Quackenbush.

R1 transfer port inserts
Dennis also made these transfer port inserts for my experiment.

I could go on!

And that’s not all. I remember the rifle that wanted to take the R1 design supersonic in .22 caliber. It weighed 11 lbs and cocked with over 50 lbs. of effort, yet was no more powerrul than an R1. Read about it here.

Today’s point

While it is possible to get more power from some airguns, it isn’t straightforward. It turns out that the people who design the guns have already gotten most of the power that’s available. But sometimes there are guns that will benefit from a tune or even a modification. An R1 is the perfect example of that.

On the flip side, though, there are plenty of airguns that are good just the way they are. You need to recognize that before you start chopping off barrels and drilling out transfer ports. Sometimes it’s possible to get more power from an airgun by using a few almost never-miss tricks — but the question always is the same — do you really want to?

A high-school buddy of mine bought a clapped-out MG TD, but since we lived in California, it was not rusted out. He put a small-block V8 engine into tit, transforming an odd, underpowered sports car into a vibrating, overpowered jalopy that overheated on cool days. But he got more horsepower — yes he did. A car like that is nice for a car show where people can dream about it, but not in real life. And neither is a mega-magnum spring rifle that takes a Hercules to cock! Save stuff like that for your daydreams, but shoot real airguns!