I stripped and resealed mine a couple of weeks ago. The buffer washer and breech seal had perished and the O ring had a piece missing (I suspect from being stuck to the cylinder bore as it hadn't been cocked for quite a few years). Pre load on disassembly was quite low, with a little pressure on the end block I was able to control it quite easily. Reassembly was a little more difficult as I didn't want to use a spring compressor in case I damaged the paint on the end block. I had to get my missus to hold the rifle upright with the barrel resting on a piece of carpet and use my considerable bulk to compress the spring and reattach the end block. Took me a couple of goes and a few sweary words to get the thread started but managed in the end