Lyman’s GPR hammer needs adjusting

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Thank you Indy, I did google it but couldn’t locate it.
Me either, looks like it's gone. In a nut shell. There is a purposeful gap inlet underneath the tang to allow the screws to be used to make adjustments for the barrel fit up. If memory serves, they wanted a very and I mean very slight bit of barrel tip up when the hook is set in the tang, like barely any at all with a warning that very much pressure can cause stock failures. That same adjustment can be used to ever so slightly lower that fitment and with any luck could offer just enough relief especially since you mentioned it changes with the weather. There is still a vid about changing that same adjustment to aid in wedge fit if they're too tight.
 
Me either, looks like it's gone. In a nut shell. There is a purposeful gap inlet underneath the tang to allow the screws to be used to make adjustments for the barrel fit up. If memory serves, they wanted a very and I mean very slight bit of barrel tip up when the hook is set in the tang, like barely any at all with a warning that very much pressure can cause stock failures. That same adjustment can be used to ever so slightly lower that fitment and with any luck could offer just enough relief especially since you mentioned it changes with the weather. There is still a vid about changing that same adjustment to aid in wedge fit if they're too tight.
Thanks again I’ll mess with it without over tightening 👍
Completely understand, if the front of the barrel is tipped up it would tip the nipple back a bit
 
Humm the barrel is not fully sitting in the stock/ tang.
See that big gap under the breech.
I'd pull the barrels and tang to see where,why it's riding high. Then do a little light inletting until everything drops in place
 
Humm the barrel is not fully sitting in the stock/ tang.
See that big gap under the breech.
I'd pull the barrels and tang to see where,why it's riding high. Then do a little light inletting until everything drops in place
Thanks, I know I didn’t sand it down very well when I put it together, it’s still pretty rough in there
 
Looks like it may take a bend to center it, then a shorter nipple to square it.

Seems to be 3 things possibly causing problem

1) The hammer

2) the snail not drilled/tapped to orient nipple properly

3) stock not inlet to position the lock in relation to the barrel

Is this a kit gun?

It would be great of you could find another GPR local, and you could swap some parts to see if that points to cause of misalinegment. That is swap hammer/barrels see if that helps.

Not sure if other Investarms use the same hammer? Or if hammers changed over the years.
 
Looks like it may take a bend to center it, then a shorter nipple to square it.

Seems to be 3 things possibly causing problem

1) The hammer

2) the snail not drilled/tapped to orient nipple properly

3) stock not inlet to position the lock in relation to the barrel

Is this a kit gun?

It would be great of you could find another GPR local, and you could swap some parts to see if that points to cause of misalinegment. That is swap hammer/barrels see if that helps.

Not sure if other Investarms use the same hammer? Or if hammers changed over the years.
Yes gun kit from 1999. Good idea about buying another used one. And you gave me another idea. I have the original 1-60 twist barrel that I could swap and see if any changes. A few years later I bought the hunter barrel because I thought it would be more accurate and that’s what stayed on it. Can’t believe I didn’t think of switching them out just to see.
You guys certainly gave me some things to check and try out before I melt my hammer down like the wicked witch of the west.

I don’t want to mess around with it too much right now until Jan 15 when all the gun seasons end. I can’t mess up the accuracy, but after I’ll figure it out one way or another.

And if anyone would like to know how I fixed it (or wrecked it) I’d be glad to post it
 
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