Assembly...Help!

[fisherhahn]

I've been making some antler/30.06 bullet pens and have been crushing numerous actions when trying to assemble them. I can't for the life of me figure out why. I've been using standard 7mm tube form PSI, cut to length and soldered into the rifle shell. I'm making sure there is NO glue or solder inside the tubes. I have even been sanding the crap out of the inside of the tube to try to get an easier fit when pressing together. The last couple times I also tried hitting the brass end of the action on my buffing wheel to polish it up for a smoother fit and the actions still keep sticking and then buckling. I had put together 100's of other 7mm pens and never had this problem. I was thinking maybe bad tubes from PSI, but they fit the mandrel and mill just the same as any others. I'm stumped. Any suggestions?

 

[KCW]

Try drilling with a 9/32" drill bit, to give the brass tube room to expand, when the transmission is pressed in. I got this tip from Billy Tallant (Sataro) when I started making these, and it fixed the problem.

 

[fisherhahn]

I don't think drilling with a larger bit would make a difference because the tube is soldered in not glued. Maybe I could try drilling the larger hole and gluing that end, while soldering the tip...

 

[eharri446]

If the tube is solder in, that may be the cause of your issue, the tube cannot expand that little bit that is required to allow the action to press in.

 

[ed4copies]

Try pushing the transmission into a tube, apart from the pen (Experiment to see if the same thing happens!!) IF it does, your problem is the size of the tube or tranny. IF it does not, the problem is your casing body construction.

Once you isolate the problem, you have a better shot at fixing it.

NOT ALL transmissions are identical size, not all "7mm" tubes are identical size--find a combination that works outside the casing, THEN see if there is a problem when you use them with the casing.

 

[traderdon55]

The 30.06 shell does not allow the brass tube to expand like it does in wood which causes the transmission to crush. I have found that if i run a 1/4 inch drill bit into the tube just before I press in the transmission in it shaves just enough off the inside of the tube that the transmission goes in without crushing and still fits well.

 

[Rick_G]

Check out Dave Bell's article in the library on bullet casing pens. He made a small swaging tool and enlarged the inside of the brass tube a little before putting it in the casing. This allows the end of the transmission to go past the brass in the casing before it starts to expand the brass tube.

 

[fisherhahn]

Thanks guys! Guess I should have done a search to begin with....