You will want to order the cocking link arm and the pin that holds it to the barrel breech. That pin can be hard to remove from the barrel you have now and this way you will have two complete set ups making it easy to switch calibers when needed/wanted. This diagram is for a NP2 gun but it would be the same parts that you need. Number 13 and 6.
You can reuse 3,6, 13, 14, and 22, providing they are not damaged in the disassembly. 14 IIRC will not need to be removed as 13 and 14 should come out as an assembly. You will want a new breach seal as the new barrel will not have one. It is a very easy and straight forward swap.
I replaced a barrel on my trail about a year ago and at first I thought it would be difficult but its really not. So here is a step by step.1: insure gun is not cocked and loaded and on safe.2: remove action from stock 2 screws IIRC on the under side.3: loosen #5 before you remove pivot screw #4. Retain #3 for reassembly with new barrel.4: Drift out #6 noting which direction as it is tapered and must go back in the same, along with #22 and 13.5: apply grease of choice to pivot area and reverse process to put back together.
Try hitting from the other side. There is no set screw. That is on the NP2 series.
The oval end goes through the similar shaped opening in the cocking slot and rests in the cutout in the piston. Insert it before the pivot screw.
Quote from: mobilehomer on December 16, 2019, 10:47:06 PMThe oval end goes through the similar shaped opening in the cocking slot and rests in the cutout in the piston. Insert it before the pivot screw.Is it supposed to look like this?
Quote from: Martin trj on December 16, 2019, 10:52:24 PMQuote from: mobilehomer on December 16, 2019, 10:47:06 PMThe oval end goes through the similar shaped opening in the cocking slot and rests in the cutout in the piston. Insert it before the pivot screw.Is it supposed to look like this?Yes, just lined up better.There are several way to remove the chisel. It MUST be pushed in. Then the pivot bushing has to be pushed out. 5/16" or 8mm. I cushion my vise jaws. I clamp at the yellow arrows while pushing the chisel(red arrow)in with the side of the vise. Clamp snug, push in, then tighten. Drive out the bushing. Then the reverse to install in the new block. Make sure the bushing is flush with the sides of the breech block and not protruding.