Special tools for airgun repairs
by Tom Gaylord
Writing as B.B. Pelletier
This report covers:
- Air Arms End Cap tool for the S410/510
- Air Arms piston seal tool
- Seneca tool for ring nuts
- Beeman R9 end cap plug removal tool
- Gene’s special tool
- FWB 124 compression chamber scraper
- Another scraper
- BSA mainspring assembly tool
Today’s report was inspired by Gene Salvino, the senior technician at Pyramyd Air. He showed me the pellet removal tool he made from a broken .177 Dewey cleaning rod and asked me to show it to you. I did in Part One of the 2019 Pyramyd Air Cup report and there was so much interest that I decided a report on special tools was in order. Now this comes on a Friday, so there is all weekend for you to post pictures of, and tell us about your own special tools.
I will start with the tools I’m the least familiar with. Then I’ll finish with a couple tools I have made myself and used over the years. Let’s get started.
Air Arms End Cap tool for the S410/510
Air Arms PCPs have holes in their end caps (where the filling is done). To remove these caps you need some kind of a spanner with pins that fit into the holes. Air Arms supplies a tool for this job to their dealers, and Gene says he uses it on S400s, S410s, S500s, S510s and whatever other pneumatic Air Arms may bring out, because they keep things standard for reasons like this.
Air Arms piston seal tool
Another special tool Air Arms provides is for installing piston seals on their TX 200. The TX piston has a flared steel top that the seal must expand to go over. The flare then holds the seal firmly on the piston.
I will show you the tool with a seal mounted and piston that’s ready to be sealed. Then I will show the detail of how the tool works.
The tool is two parts. The flared part slips into the handle, so you can install the piston seal easily. Put the seal on the small part of the flare with the bottom heading forward, so it ends up on the TX piston in the right orientation.
Gene says he doesn’t get to use this tool as often on TX200s because they seldom need new piston seals, but the same tool works on all Gamo rifles that have one-inch tubes, Stoegers from the X5 to the X20 and on certain Crosman/Benjamin Trail rifles. So it’s a handy tool to keep around.
He says if you plan to make one for yourself, make the wide end a little larger and it will also work on RWS seals.
Seneca tool for ring nuts
On Seneca pneumatics the end cap that holds the fill port is in a cap that’s held on by thin ring nuts. The nuts have two small holes on opposite sides that a spanner goes into. Boris made a tool for Gene that has two cap screws with their ends machined round and smaller to fit these holes.
This spanner for Seneca PCPs looks massive, but it’s not. The ring nuts it fits are about an inch in diameter. Boris made it from stock steel, but you could make one from a small C-clamp, too. The screws are M5 metrics.
Beeman R9 end cap plug removal tool
Gene made this tool and he says he uses it all the time when working on Beeman R9s. The R9 has an end cap that holds the trigger and keeps the mainspring under tension. It’s a sleeve that fits inside the main spring tube. It’s held in the tube by a single flange, but its also held by 4 square tabs that must be popped out before the sleeve can be rotated so the flange can clear the spring tube.
I have always popped out the first tab on either side with the short leg of an Allen wrench. The trouble with that is the wrench tries to twist in your hand and sometimes a tab is really stuck tight! Once a tab is popped out a pin punch will pass through the hole to easily pop out the tab on the other side of the tube.
Gene’s special tool
Gene bent a heavy piece of wire to reach in and pop out the tabs. He then uses a pin punch for the opposite side.
If I’m not mistaken, there are other Weihrauch rifles that use tabs like this. I think the Beeman R10 that is based on the HW 85 uses them, as well.
FWB 124 compression chamber scraper
The FWB 124 breakbarrel is a legendary spring piston air rifle. But the original seals dry-rotted inside the gun and all failed over time. When the gun is disassembled for a reseal, you find a lot of old seal material crammed into the corners of the compression chamber deep inside the spring tube where it’s hard to reach. So Gene made a tool to clean the end of the chamber. It includes a sharp point to get into the tight corners of the chamber where it’s hard to reach. It doesn’t look like much but he tells me it’s a tool he uses all the time. He got the idea from attending a class by Randy Bimrose who gave the students drawings of many special tools for working on spring guns.
It doesn’t look like much, but this tool is invaluable when tuning spring-piston airguns.
Let me show you how bad a 124 seal can get. These old rotten seals were stored in the wooden box that my 124 came in. They were in plastic bags that are not airtight. They started out as off-white color but look at them after 30 years!
These FWB seals have rotted and turned to a waxy substance that crumbles to the touch.
Now I’ll show you a couple special tools I have used. I used to scrape the compression chamber with a long-bladed screwdriver. It works but isn’t as good as what Gene has. However, a few years ago I discovered that the patch removal tool for a muzzleloader is just about perfect for the tight corners.
The patch removal tool on a Thompson/Center Hawken ramrod is great for picking old seal material out of the crevices of the compression chamber.
BSA mainspring assembly tool
Some spring rifles have a large pin that stops the mainspring from coming out of the gun. You have to get around this pin to push against the spring guides to take tension off the spring or the pin will not come out.
To compress the mainspring you have to get past that large pin.
This 58-cent plastic sprinkler pipe makes a good mainspring compressor that reaches around the BSA pin with ease. It looks crude, but I have taken several BSA spring guns apart with it.
That’s it for the special tools. Maybe you have one or more to share?