Tx200 Lock Up Test and Fix

[Springrrrr]

I posted a link from the Airgun Forum in the UK that had a great post on how to check the lock up on a TX200.  Here it is again for anyone who may have missed it.
http://www.airgunforum.co.uk/forums/showthread.php/165327-The-TX200-cocking-shoe-cylinder-lock-up-issue

The author, Cloverleaf, suggested to use a shim like this  I___I  under the cocking shoe to take up the slack needed for a positive lock up if necessary.  Maccarri used to make over sized shoes but he no longer does, so unless we can find another to make one, we are stuck with what we got.

That shim may raise the shoe in its slot and cause problems of its own so when I got mine back from warranty, I decided to check the lock up and it was OK but still a bit weak.

Instead of going with the shim under the cocking shoe, I silver soldered a shim to the front face of the cocking link (part TX 290).  Because all the cocking linkage is rigid when closed, the installed shim, when the cocking arm reaches the end of its travel and closes in the ident ball assembly, pushes the shoe against the front shoulder of the slot on the compression tube that it sits in, thus sliding the tube further forward and harder against the breech.  This move makes sure the breech seals are fully compressed against the pellet port when the gun is in the ready to shoot condition.

I used a steel shim about .008 thick from stock I had.  Even if it flattens the breech seals more that they normally are, it is cheaper to replace them than to buy a new cocking shoe if it breaks due to a poor lock up.

I also found out that Air Arms had some quality problems with some compression tubes.     Air Venturi, the repair facility, told me they've seen a few of them crack (like mine was) and some are out of round.  I don't know, at this time, if all those issues have been resolved.

Another thing anyone that has purchased a TX recently should do, is take a flashlight and have a look into the breech area below the port the pellet gets loaded into.  I found a large gob of very hard green thread sealer stuck to the side of mine that I had to use solvent and a pick to remove.  That probably was another reason my gun was not locking properly and broke the cocking shoe.