I did a bit of tinkering and plinking today and if anybody is interested, this is what I did.
I have a .22 Tempest fitted with a Typhoon spring. I normally shoot with Milbro Caledonian pellets but have used Marksmen recently, which shoot ok but don't seem as good a fit as the Milbros. I did try Some Hobby pellets that John (the back half of Josie and John
) sent me and found them to shoot ok.
I found a couple of mainsprings today. One was a broken round section one that came out of a Hurricane (Typhoon spring maybe?) and the other was a squre section spring that went in the gun ok so might be a Hurricane or Tempest one. I collapsed a coil on the broken spring and cleaned it up. I tried it and I seemed to be getting a fair few fliers. The point of impact had moved left as well. I did another coil with similar results. I guess the spring was now 5/8 to 3/4 shorter than standard. The gun did not feel particularly weak and it was easy to cock and the trigger was a bit lighter.
The Hobby pellets seemed best although the grouping was not brilliant.
I then tried the square section spring and the point of impact was also left, so maybe I had knocked the sights. The grouping was better but still not brilliant. The gun was harder to cock.
I went back to the Typhoon spring I had in the gun in the first place and the groupings had tightened up. I adjusted the sights and by the time I wrapped up I had put 6 pellets in a group the size of a bottle cap. I then shot 3 bottle caps. The pistol was shooting a fraction the the right but I left it at that.
I have a feeling that with a .177 rather than the .22 that collapsing 3 or 4 coils on a Typhoon spring might help as the .177 pellet will be lighter and travelling faster than the .22.
I prefer .22 and am happy with my £50 Tempest with the Typhoon spring