Cadet Major

[pennineway.fswo]

Over the Xmas period, i have kept myself sane by stripping and sorting a couple of sick HW45's(thanks for parts info David)

I also decided to strip and improve the performance of one of my Cadet Majors

I own one, that I changed the leather washer to PTFE some time ago, and this improved the pellet velocity of that particular rifle from about 570 to about 630 ft/sec.

The one I decided to strip and improve still had the standard leather piston washer and the velocity with 7 gr. pellets was about 600 ft/sec.
Although 600ft/sec is fine for a Cadet Major, the rifle was very harsh to shoot, stock screws were always coming loose, and it was obvious that the piston was striking the end of the cylinder too hard.

On stripping, I found that the leather washer had burnt away/receeded a little, such that it was no longer proud of the nut holding it in place.There was also evidence that there was metal to metal contact at end of cylinder
A new washer seemed to be the solution. However, new leather washers are a pain to make and take a lot of running in. So I decided to shorten the spring slightly(3 coils) and dress back the stud and nut holding the washer and backing in place.
I put the gun back together and tried it out on a 10 metre range. It shot perfectly , grouped well, and was easy to cock.
I guessed that there would be some trade off with power/velocity and I would have been very happy if the gun was arround 550 ft/sec.

Big surprise , despite the very smooth shooting cycle, the rifle was now spitting out the light weight wadcutters at about 660 ft/sec. So power was up by well over a ftlb.
The gun was so smooth to shoot that I did not believe the chrono. figures and so checked it out on the clubs chrono. Same result! and virtually no evidence of deiseling(although i am aware that some controlled dieseling must be taking place for such a little gun to be developing about 6 ft. lbs of energy)

I have noted in the past, that on underlever rifles (with loading taps)such as the Airsporters mk's 1-7 and Webley Mk111's; power can go up on fitting a weaker spring, particularly if the rifle is obviously oversprung and is harsh to shoot.

However this Cadet Major is the first old break barrel rifle that has benefitted in several ways by shortening the spring.

[stuart]

Just goes to show that bigger or longer isn't always best or so my missus says anyway its nice to see you've kept busy over the festive period regards Stuart