Misfire

[Ruskin]

I have been working up a 357 max load.  I changed to my 30-30AI.  I had a hammer extension on.  I had two misfires.  I then took off the extension. I had one more misfire.

I wonder if the change from a pistol cartridge where I was using small rifle primer to a 30-30 with large rifle primer had anything to do with it?

Perhaps the primer case is thicker?

[tlyne]

No,T/C Frames with hammer extensions slows down the hammer speed and causes misfires.

[Ruskin]

is there a spring change that can be made?

[Bullseye]

Long story short, years ago I had misfires with all kinds of barrels.  Took the hammer extension off both times I sent it to T/C.  After the third time when I called pretty upset the gunsmith ask me if the gun had a hammer extension on it and I said yes.  He said that was the problem.  I have told you nothing new so far.

He went on to say that just taking the hammer extension off would not fix the problem since the extra weight messed up the spring and told me to send it in at he would put it at the front of the line and put new springs in it.  15 or so years later and never any more problems.

Did it hurt the springs?  I do not know since I sent it in without taking the extension off and trying it.  Always seemed strange to me, just passing on what a gunsmith at T/C told me and what he did to fix my mis-fire problem.

[blhof]

I had a similiar problem a few years ago with a new 30/30 barrel and called T/C and they put me through to the smith who's first question was, did I have a hammer extension, which I did.  He said remove it and try it and to let them know as the spring will have to be replaced if it persists.  Removed the ext. and problem stopped.

[expeditionx]

I had a similiar problem a few years ago with a new 30/30 barrel and called T/C and they put me through to the smith who's first question was, did I have a hammer extension, which I did.  He said remove it and try it and to let them know as the spring will have to be replaced if it persists.  Removed the ext. and problem stopped.

That seems to follow the TC faqs question #20
20: Does Thompson make a hammer extension for the encore?
 No, we do not recommend a hammer extension, however a conversion for the Pro-Hunter swing
hammer will be available in October.

Not from TC:
WARNING: DO NOT USE STEEL HAMMER EXTENSIONS ON ENCORES OR G2S!
Encore and G2 hammers are quite frail and will often readily bend forward and break
from the extra weight of a heavy steel hammer extension, especially if overtightened.
Contender hammers are much, much more strongly designed and will not bend or break
 due to the weight of a steel hammer extension, so steel IS ok on Contender hammers.
However, for fastest lock time, aluminum is half the weight of steel and is preferred.
For those who prefer steel Contender hammer extensions, periodically replace the
 hammer spring with a fresh factory supplied spring.