Mechanics of barrel lock up

[Incitatus]

I now have 5 frames (all old style) and a bunch of barrels.  I am beginning to find the variability of what works with what sort of irritating.  Some barrels don't fire with some receivers and some are very very tough to open, even to the point of having to take parts of the receiver apart in order to separate them.

Some questions:

- how do the mechanics of the lock up work?  Are there any diagrams that explain it?

- is it mainly a function of the lock on the barrel?  Might one design a "universal" lock that  would work equally well with all receivers? 

[SHOOTALL]

When I was shooting them I was shown to coat the bolts (the wedge looking things on the bottom) with a magic marker and close the gun . Open it and the bolts should show marks half way up. You can get extra bolts to adjust a frame. It might be hard to adjust all frames to fit with all bbls.

[Flash]

The locking lugs on the bottom of the barrel make all the difference. I used to hone mine with a Dremmel tool to make them all work the way i like.

[shot1]

In theory the Contenders were designed to work with any barrel on any frame. In reality it is best to fit a barrels lugs to just ONE frame for best operation and accuracy. You can swap barrels off and on to that one frame but fit all barrels to it. When you start swapping barrels and frames is when you run into trouble. Just my 2 cents worth from experience.