Senior Pistol piston...

[laverdabru]

A while ago I bought an early '60's Senior. Apart from a missing keeper screw, soon replaced, it looked OK. But it was very hard to cock. So hard I decided not to use it until I'd had time to have a decent look at it, in case I damaged anything.

So, had a close look today.

Looking thru the aperture where the cocking mech fits in, there appears to be a crack running at an angle across the piston body.

Chambers list a replacement piston for c. £28, but not the seal.

Has anyone else had this problem, & if so any other issues I should look out for? I've owned Webley pistols since the early '70's, & never seen a cracked piston before...

All the best

Bru

[Mr. Gen]

you need to strip it down first to see the full extent of the condition.....

[pjbingham]

Like you I've stripped alot of Webley pistols over the years and I've never seen a cracked piston! Is there any chance you could add a couple of pics once you have stripped it please,interesting to see. Atb Phil.

[Mark D]

Just be careful as you unwind the end,as it may have been fitted with a non original spring. Never seen a cracked piston,but always a first time. Could just be a hair or something that's got in there.

Pictures....

[laverdabru]

I'll be stripping it down over the next few days, grandchildren & work allowing.

Never had a broken piston, even on the much abused pre WW2 Junior & Mk 1 back in the '70's.

Will have a look at posting pics.

Bru

[ggggr]

Many year ago, I had a Senior that I guess had been abused and the piston had "belled" on the body between the thicker parts at the front and rear of the piston. This would caused the links pins to snap as the "bell" jolted the short link on firing. Eventually I found someone to take a bit off it on the lathe and many years later it is still working.
I guess the thing had been dry fired many times to cause the problem.

I have seen and heard of damaged flanges where the sear engages. I think this can be caused by shooting with a damaged piston washer (not on the bronze ringed Senior) as the piston can travel further up the cylinder.
Also on a Mk1, the thing had so much rust in it, it stopped the piston travelling all the way back on cocking and resulted in a worn flange. A clean up with a file got it working and then just to be safe, somebody took a few though off the flange to clean it up.

[laverdabru]

Well, stripped the piston side of things today.
There is indeed a crack around about 70-80% of the piston circumference.
It is in the 'long' part, in front of where the cocking link engages, if you see what I mean.
Apart from that, no other signs of damage so far - even the (piston) ring looks reusable.

But I'll fit a new piston, also breech seal & standard spring to be on the safe side. The spring did look a bit large.
Thanks for all your advice, I'll update when the new parts are fitted.

Bru

[laverdabru]

The new spring & piston arrived today, & were fitted within 30 minutes. Certainly feels much better, but still not nearly as smooth in the cocking action as my Premier/Tempest/Hurricanes.
Is this just down to the more complicated linkage on the Senior, or should I be looking for other problems?
This is my first rebuild since my Webley Junior/Mk 1 some 30 years ago, so please be gentle with me.

Bru