Checking out a Diana RWS 34P: Part 4
by Tom Gaylord
Writing as B.B. Pelletier
This report covers:
- Happy birthday, America!
- Vortek Pro Guide 2
- Disassembly — Rail Lock Spring-Compressor
- Spring break!
- Removing the piston
Happy birthday, America!
Today the U.S. celebrates 241 years as a nation. It will be loud tonight (fireworks)!
Today I install the Vortek Pro Guide 2 tuneup kit in Geo791’s .22 caliber Diana RWS 34P. Now that we know his rifle is accurate it will be nice to also know that it shoots at the top of its form.
Vortek Pro Guide 2
Pyramyd Air doesn’t sell this kit, so if you want one you’ll have to get it direct from Vortek. The kit consists of instructions, a new mainspring, a special new spring guide, a synthetic top hat/forward spring guide, new piston seal, new breech seal and grease.
The mainspring in this kit appears to be made of good spring steel. I know that Diana has had problems in the past from over-hardening their mainsprings, so this tuneup should ensure George a long time of good operation with his rifle. The piston seal is also special and I will cover it in a little bit.
The new spring guide fits around the outside of the mainspring instead of the inside. You may remember that a coiled mainspring expands slightly when compressed, so this guide will become tighter rather than looser when the gun is cocked. As the kit comes, the guide is already on the spring extremely tight, so there isn’t going to be any vibration in this area!
Disassembly — Rail Lock Spring-Compressor
To fit the kit the rifle must first be disassembled. I used the Air Venturi Rail Lock Spring Compressor to remove the mainspring. This is the second type of action I have used the Rail Lock on and it works like it was made for Dianas!
Once the compressor was in place, I put a little tension on the trigger block and both pins that hold the trigger block in the spring tube came out. The action came apart in seconds, making this the fastest I have ever disassembled a Diana. The Rail Lock is the reason for that.
Now the spring guide and mainspring could be removed and, once they were out, I saw something that I have seen many times before. The mainspring was broken about one inch from the end on the spring guide end! This is a very common fault with Diana spring rifles, though I thought they had corrected it in the past decade. The unbroken end of the mainspring has a small cant in it, as well. So, George was lucky that I decided to tune his rifle! I actually wrote a report about this in 2006 titled, Spring Break.
Remove the piston
The next step is to remove the piston. The barrel has to come off for this, because the cocking link must be separated from the piston body. Dianas are made to come apart easily this way and I had the barrel off in less than a minute.
The piston seal in the rifle was like new, but since the Vortek kit has a new one, I removed the Diana seal. Getting the new Vortek seal back on the piston, though, was not easy. It took me all of 45 minutes. I found that the seal material likes to be warmed by flexing, before it will hook the flared top of the piston. But I got it.
I lubricated the piston seal (very sparingly), the rear of the piston body and the mainspring with the special grease that came in the Vortek kit. The Vortek owner, Tom Gore, tells me this piston seal will wear in to become incredibly slick with use, so it doesn’t need much lubrication.
I put a bit of extra grease at the mouth of the spring guide, since I couldn’t get the mainspring out to lube all of the coils. Cocking the rifle will spread this grease back on the back coils of the spring.
The rifle went together just like it came apart. Once more the Rail Lock compressor was easy to install and operate. I discovered the Vortek spring was a little longer than the factory spring that had the last inch broken off.
The last job was to replace the breech seal. The old one looked fine, but since the kit came with a new one, I installed it.
Start to finish this job took 2 hours. That time includes taking pictures and 45 minutes fiddling with the piston seal.
After that I finished the assembly and went to my range to test-fire the rifle. How did it do? That’s coming tomorrow.