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.he CHAPTER 11 CORBIN HANDBOOK AND CATALOG NO. 7, PAGE #

                                  DRAW DIES 

        Draw dies,  or drawing dies (as they are also called),  are simply 
   ring dies used to reduce the diameter of a component.   When you size a 
   cast  bullet,  you are using a much less precise version of a draw die.  
   The draw dies made by Corbin are extremely hard,  tough  venturi-shaped 
   tools held in a 7/8-14 TPI body.   A punch pushes the component through 
   the die and out the top.  
        There are two general types of draw dies.   The JRD-1 can be  made 
   either  for  bullets,  or for jackets.   The bullet draw die reduces  a 
   finished  bullet  by  a small amount,  sometimes as  little  as  0.0005 
   inches,  and  sometimes  as much as  0.003  inches.   However,  greater 
   reductions cause distortion of the bullet and are not feasible.  
        Jacket draw dies can reduce an existing jacket by a whole caliber.  
   This  is  the  way that .41 caliber jackets  are  obtained  today,  for 
   instance.   A  .44  caliber  jacket is pushed through a  draw  die  and 
   reduced  to .41 caliber.   This would not work with a  bullet.   Jacket 
   drawing  punches fit inside the jacket,  and actually push  it  through 
   base first, while bullet draw dies push the bullet through nose first.
        Special  versions of draw dies turn fired .22 cases into  .224  or 
   .243  caliber rifle jackets.   The .22 WMR case can be drawn to a  long 
   6mm jacket in another die,  and shotgun primers can be turned into free 
   .25 ACP jackets with another.   Draw dies perform a remarkable service. 
   Their  limitations  are  discussed in "REDISCOVER SWAGING"  in  detail.  
   Dies  ending in "R" fit the standard reloading press and have  a  punch 
   that  fits  into the press ram.   Dies ending in "M" fit the Mity  Mite 
   press,  and have a punch that screws into the press ram.   The die goes 
   into the press head,  replacing the floating punch holder.  Dies ending 
   in  "H" are made for the Corbin Hydro-press.   They have a  long  punch 
   that screws into the ram,  and the die fits into a 7/8-14 adapter which 
   in  turn fits the 1.5-12 thread of the press head,  also replacing  the 
   floating punch holder.  
        
        RFJM-22R       Rimfire Jacket Maker, 22 LR to .224 caliber
        RFJM-6MR       Rimfire Jacket Maker, 22 LR to .243 caliber
        SPJM-25R       Shotgun Primer Jacket Maker, 25 ACP caliber
        JRD-1-R        Jacket Reducing Die,  specify starting and ending
                       caliber.

        Draw  dies  for the reloading press are used by adjusting the  die 
   position  so that you can push the component through the tightest  part 
   of  the  die  using the end of the  stroke.   Careful  die  setting  is 
   necessary so that the component is pushed far enough into the die,  yet 
   the  more  powerful portion of the stroke is still  utilized.   If  you 
   simply  put  the die in the press at random settings,  it might not  be 
   possible to push the component far enough so the next component  pushes 
   it out the top.  Or, it might require so much effort that the operation 
   becomes impossibly difficult.  
        It  is  important to realize that effort varies quickly  with  the 
   exact  part  of the stroke where the most resistance is met.   This  is 
   adjustable by your setting of the die.   Too high, and the press easily 
   pushes the component in,  but not nearly far enough.   Too low, and the 
   press has little leverage or power to do the job,  even though there is 
   plenty of stroke to push the component through.  The optimum adjustment 
   can be found in a few attempts, if you bear the critical nature of this 
   balance in mind.
        It  might  seem  as  if a draw die is a very  inexpensive  way  of 
   creating a custom bullet.  In a few limited instances, it is.  But, for 
   most calibers, reducing an existing factory bullet to a smaller size is 
   more  expensive than making it yourself,  produces a far less  accurate 
   bullet,  and  limits  you  to the same weight and basic  style  as  the 
   factory bullet itself.   Giving up the advantage of superior  accuracy, 
   the ability to make the bullet in any weight or style you wish, and the 
   cost  savings  of using jackets and lead instead of  buying  ready-made 
   bullets,  seems  like  quite  a bit to give up just because  drawing  a 
   bullet down seems simple.
        The lure of getting an inexpensive bullet-production die sometimes 
   overwhelms  one's sense of values,  though,  and it isn't uncommon  for 
   someone  to  sacrifice all these advantages -- all the  real  power  of 
   bullet  swaging -- in order to draw down some existing bullet.   In the 
   instance of the .357 and 9mm,  the two 8mm diameters,  and sometimes in 
   the reduction of a military bullet purchased very cheaply in  quantity, 
   the process works well enough to justify the lost advantages.  It isn't 
   a general cure, and it certainly does not replace swaging your own.
        On the other hand, a jacket draw die makes good sense.  The jacket 
   will  be  expanded  by internal lead pressure during  swaging,  so  any 
   diameter  changes  made  to  it are rather  unimportant  to  the  final 
   product.   The ability to change standard diameters, to use an existing 
   longer jacket or heavier design in the next smaller caliber,  is a good 
   advantage.  Sometimes, it is the only way to obtain a good, inexpensive 
   jacket.   In  .41 caliber,  a drawn .44 is the standard jacket used  by 
   bullet swagers.  Likewise, for the .40 calibers. 
        One  does pick up a little longer draw on one side of  the  jacket 
   when  the reduction is extreme.   This is unavoidable without extremely 
   high cost equipment,  but its effect is primarily cosmetic:  the tip of 
   an  open  tip  jacket may  appear  uneven.   Accuracy  generally  seems 
   unaffected  by  this,  since the jacket walls themselves seldom  become 
   eccentric in any normal drawing operation.  
        A  set of dies to make .14,  .17,  and .20 caliber bullet  jackets 
   from commercial .224 0.6-inch length jackets is available from  Corbin.  
   The  process of making sub-calibers involves drawing the standard  .224 
   jacket  through these three stages,  stopping at the stage you  desire.  
   The  jackets  must be annealed after the first draw (from .224  to  .20 
   caliber)  or  else  the end will break out on the next draw  or  during 
   swaging.  
        Since the jacket for a .17 or .14 usually is shorter than that for 
   a .224,  the jacket must be trimmed at some point.  This can be done in 
   the  first draw,  from .224 to .20,  using a PINCH-TRIM die and  punch.  
   The punch is made with a shoulder,  so that the shoulder to tip  length 
   determines  the length of the jacket.   Any jacket that extends  beyond 
   this  punch  step or shoulder will be sheared off as the  punch  passes 
   through the die constriction.  
        The process works well provided the correct jacket is used,  since 
   the temper,  grain, and diameter as well as wall thickness are somewhat 
   critical for proper shearing action.   Usually, the jacket will be made 
   quite short,  and will be drawn longer in the .17 and .14 stages.   The 
   exact  final length is a bit experimental,  since variations in  jacket 
   lots,  temper,  wall thickness, and material composition will produce a 
   somewhat  different final drawn length.   But it seems quite consistent 
   within one lot or kind of jacket.  
        Jacket  and bullet draw dies that fit the reloading press  or  the 
   Mity Mite press require careful adjustment so that the maximum leverage 
   can  be  properly utilized to push the component through  the  tightest 
   point  in  the die,  yet still gain maximum stroke within the  required 
   leverage range.    In some cases, such as drawing copper tubing to make 
   long rifle jackets,  there isn't any easy way to get enough stroke  and 
   enough  power at the same time.   In those instances,  a short "helper" 
   punch or rod must be used.                 
        The jacket is drawn in two stages.   First,  the jacket is started 
   into  the die using the end of the stroke,  where there  is  sufficient 
   power.   Then,  the  ram is drawn back,  the helper rod inserted in the 
   jacket,  and the ram is run forward again, gaining extra stroke to push 
   the component all the way through the ring die.  This is, admittedly, a 
   slower way to do the job.  But in some cases, it is the only thing that 
   works in a hand press.
        Dies made for the Hydro-press,  on the other hand, seldom have any 
   such   difficulties  because  the  programmable  Hydro-press   develops 
   whatever  power is needed,  at any point in the stroke cycle.   With  a 
   full  six  inches of stroke to work with,  and full power from  top  to 
   bottom,  it  is a simple job to draw just about any length or thickness 
   of  jacket  in one stroke.   Copper tubing jackets are a  product  that 
   point up the advantages of the Hydro-press design.
        Remember   that  in  most  home  swaging   operations,   you   are 
   accomplishing  tasks  in very few steps,  with  relatively  inexpensive 
   equipment, that the major factories spend tens or hundreds of thousands 
   of dollars in time and equipment to accomplish,  often in 10, 12, or 14 
   stages.   Sometimes,  there  are obvious limitations to what you can do 
   without a bit of leeway in your final lengths or weights.   (Sometimes, 
   the amazing thing is that the process works at all!) 
        On the other hand,  for the person who doesn't mind  experimenting 
   and  can put up with things coming out just a bit differently than  his 
   original blueprints might have demanded,  these processes offer a great 
   deal  of  freedom from high costs,  abritrary supply sources,  and  the 
   ability to make bullets that are extremely accurate and unusually  high 
   in  performance.   Just  don't  confuse accuracy and  performance  with 
   predictable adherence to a pre-existing design concept!  Sometimes, the 
   way  it  happens  to come out is what you have to  work  with,  in  the 
   practical  world of limited costs,  simple  operations,  and  available 
   supplies.   Fortunately,  the  way it comes out is usually pretty  darn 
   good!