slightly loose barrels
 

Looking at a Parker a few days ago, I mounted the gun and then broke the gun open. When looking down the barrels I noticed the barrels were slightly loose rocking back and forth sideways, but locked up tight. The hing pen appeared to be timed properly. What is the problem and is it costly to solve. Thanks in advance.

Probably not a problem. Take the forend off of the gun still locks up tight with no perceptible play it's fine.

The hinge pin screw position has nothing to do with the tightness of the gun.

The situation that you have, is a loose on the hook when open. It is not uncommon on guns that have had a good amount of use. The forend is the last piece of the puzzle in fitting up barrels and it relys on a very snug fit against the back of the forend lug and good contact of the hook on the roll joint. The one downside to the deely style forend latching is that as it wears, it does not compensate, such as the Trojan style spring loaded forend does.

The issue you describe is fixable with a few different methods. It varies from gun to gun depending on how much wear there is and where it is.

To be precise, the Parker latch is a less-than-best modification of the Deeley system. Why? To avoid patent infringement and/or royalties. Nonetheless, the Parker latch still works fairly well.

Unless I'm misunderstanding what he saying there is side to side movement when the gun is open. i.e the barrel hook is worn a bit in the sides and there is a little more clearance than typical. Doesn't seem like that is an issue that needs resolving or has anything to do with the forend.

The OP said "slightly loose" and this term is open to interpretation, however....

To treat the symptom a shim of the necessary thickness can be fitted to the roll pin.

To cure the disease the barrel hook can be welded up and precision machined for the perfect fit. Then the forend loop may need to be addressed to assure the correct fit.





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But a worn or improperly fitted forend will make the best fitting joint feel loose when open.

My grandpop tightened my W&C Scott 10 up 50 years ago with a kinda shim around the hinge pin . My gunsmith buddy tightened my 10 lifter up with a little weld I'm not sure where .