a broken mainspring on old guns it's a pretty common problem let me show you how to make a new
one this is a marlin Ballard number two sporting rifle in thirty two long it was made in the 1880s
the bore is nice and bright and it can still be shot with obsolete thirty-two rimfire ammunition
if you can find it sometimes it misfires because the hammer doesn't hit the firing pin with enough
force as the mainspring is weak another issue is the hammer won't hold in the half [ __ ] notch
this is where the phrase going off half-cocked came from as pulling the trigger may cause the
hammer to fall when the hammer is and the safety or half [ __ ] notch I'll need to remove the
breech block to take a look it's held in by a single screw next the extractor is removed and
the breech block and lever are slipped from the receiver the breech block is constructed of two
halves which are held together by several screws after each screw is removed I push it into a piece
of cardboard to ensure it goes back in the same location it came from with all the screws removed
I tap the halves apart one interesting feature of the Marlin Ballard is the ability to switch
the firing pin from rimfire to centerfire although extremely rare today 32 Ballard
centerfire ammunition was available when this gun was produced with the breech block split apart
it's easy to see this mainspring isn't original to the gun I pulled a mainspring from another
Ballard to show the difference this mainspring design evolved from a V type spring as seen in
this earlier guide the firing pin also changed early Ballard's were rimfire only and the firing
pin was an integral part of the hammer one design remained fairly constant the trigger return spring
the original mainspring isn't arched as much as the replacement and the original has a round boss
on the front to minimize friction wear the tip of the spring contacts the hammer it's pretty simple
to make a new spring from standard spring steel stock the stock comes annealed or soft and will
need to be heat treated to make it into a spring I've selected a piece as thick as the ends of the
original mainspring although it will need to be thinned in the middle after cutting the new spring
just slightly longer than the original I coat it with DICOM to show my marks more easily the proper
width is marked and I filed for the line keeping the line even with the top of the vise jaws makes
filing easier next the end of the spring is filed to shape this raised portion helps hold the back
into the spring in place by holding the springs back-to-back I can determine the correct length
the circular boss at the tip is filed and the spring is tapered from the tip to the back end
now we need to polish it lengthwise to remove all the file marks I begin with 220 grit and finish
with 320 any scratches running across the spring could cause it to break at that point the last
step in shaping the new spring is bending it to shape I'm using the original spring as a pattern
the soft metal bends easily on a spring this thin to heat treat the spring I carefully heat it to an
even cherry red color which is about 1400 degrees once the color is uniform throughout the part it's
quickly dunked in quenching oil which leaves the steel extremely hard but brittle this is a scrap
piece of spring stock that I also hardened it's too hard for file to cut and with one end and the
vise it breaks without much effort to remove this brittleness and turn the metal into a spring it
needs to be tempered which is the second step of the heat treating process tempering removes most
of the brittleness and allows the steel to flex I polished the spring Brite then place it in a pot
of melted nighter bluing salts the pot temperature is about 600 degrees reheating the steel to this
temperature removes most of the brittleness and the night herb ruling salts give the spring and
attractive blue finish wincing the spring and water finishes the heat treating process and
now the steel has its spring I install the spring back into the breech block followed by the hammer
and trigger with the newly made spring in place the hammer can't be bumped forward out of the
half [ __ ] notch but the notch in a hammer is not quite deep enough to retain the nose of the
trigger and prevent the trigger from being pulled not a problem it's a simple matter to cut the
notch slightly deeper now there's a square recess in the half [ __ ] notch to capture the nose of
the trigger with the breech block reassembled the trigger can't be pulled when the hammer is in the
half cocked position there's one more issue I'd like to fix at some point it looks like this gun
was dropped damaging the muzzle it's a simple matter to recon the barrel I begin by removing
the four in you can see the serial number on the barrel matches the receiver which is typical on
19th century guides next about plate is removed the buttstock is held on by a draw bolt again the
serial number is clearly evident last I remove the sights drifting them from left to right the
barreled receiver is fixtured in the lathe using a plug gauge the center of the bore I
make several light cuts along the muzzle until the damage is removed the outside edge of the barrel
chambered by reversing the rotation of the lathe to cut on the backside of the barrel the last step
is to remove the slight burr at the edge of the board by an abrasive on a brass lap bevels the
edge and removes the burr the face of the muzzle could be brown to match the rest of the rifle but
I'm going to leave it bright for now i reassemble the rifle and check the function for one more time