Corbin Punch Designs

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Punch Types
	PUNCH-H is a general punch type for the -H series of dies, which includes external punches, internal punches, and drawing punches (which fit directly in the press ram). External punches include the core swage external, and various end-shapes and diameters of core seating punches which fit either the ID of a jacket or the ID of the die. All external punches for swage dies fit into the floating punch holder, in the head of the press, and are retained by a bushing in the punch holder. Internal punches drop into the press ram, and do not come out of the die during operation. The length of the punch head determines how far the punch drops into the ram, and thus sets the position of the other end of the punch within the die. Longer and heavier bullets use shorter punch heads. Punches for drawing jackets or bullets fit into the press ram, and push the component through a draw die that fits the press head (instead of the usual punch holder).
	PUNCH-HA Adjustable Length (core seating or tubing end rounding), for tubing or jackets under 0.5-inch OD. This -H type adjustable punch has a micrometer-like barrel which adjusts on screw threads relative to the central portion, moving the shoulder to the desired position for a given length of tubing or jacket. In rebated boattail core seating, soft or thin jacket materials may tend to extrude forward and lengthen the jacket, taking material from the base section. This may be so severe that the jacket separates. However, even if it is not, the adjustable shoulder can be set to prevent random lengthening of the jacket because of the force of the lead trying to push forward. Adjustable shouldered punches are economical when three or more different jacket lengths may be desired, as each length would otherwise require a separate fixed shoulder length punch.
	PUNCH-HL Adjustable Length (core seating or tubing end rounding), for Large diameter tubing, 1/2-inch OD and up. Similar to the PUNCH-HA in concept, the larger size components require a different internal construction. This -H type adjustable punch has a micrometer-like barrel which adjusts on screw threads relative to the central portion, moving the shoulder to the desired position for a given length of tubing or jacket. In rebated boattail core seating, soft or thin jacket materials may tend to extrude forward and lengthen the jacket, taking material from the base section. This may be so severe that the jacket separates. However, even if it is not, the adjustable shoulder can be set to prevent random lengthening of the jacket because of the force of the lead trying to push forward. Adjustable shouldered punches are economical when three or more different jacket lengths may be desired, as each length would otherwise require a separate fixed shoulder length punch.
	PUNCH-HA Adjustable Length internal punch can be made for any die, but generally is used with a point forming die (to seal the end of the cavity for use with lead tip or all-lead bullets). The purpose of the adjustable length section is to position the end of the punch or ejection pin exactly at the end of the bullet shaped cavity so the punch seals pressure at the tip of the cavity. This prevents lead from extruding up the ejection pin hole, and allows higher pressure to be used for extrusion in custom weight-adjusting point form dies.
	PUNCH-HF Extra long funnel punch, for use with powdered metals and the Corbin FUNNEL-H precision funnel, helps you seat the powdered material into a jacket. Powder is loosely packed by its own weight, and takes up considerably more space before being compressed by seating. In fact, it takes up so much room that it won't all fit into the jacket in most cases. A normal core seating punch would simply push through the powder, blowing powder past it until it finally reached the jacket. A full die bore diameter seating punch would compress the powder to the edge of the jacket but couldn't enter the jacket. The funnel is made with a precision spout, which exactly matches the jacket wall thickness. The spouts are replaceable, and the funnel body is universal for all jackets and calibers. An extra long core seating punch pushes the column of powder through the funnel and down into the jacket without loss.
	PUNCH-HX is a special kind of custom -H punch (could be specified as a PUNCH-HC, external, core seat or core swage, X-style or cruciform) made either to fit a core swage, or a core seat die, and to put a deep X-cut into the lead core. When used with a core swage die, the x-cut core is coated or filled with lubricant or a powdered filler to prevent the cuts from closing entirely in the core seating operation. When used with a core seating die, the core is normally seated first with a regular flat end or hollow point core seat punch, and then the X is pressed into the core. The purpose is to help the bullet expand evenly into four "petals" as the jacket ruptures and expands on impact.
	PUNCH-HS is a special kind of custom -H punch (could be specified as a PUNCH-HC, internal, core seat, Saber Tooth or cruciform) made to fit a core seat die, and to put a a series of six notched in the jacket end. The Saber Tooth design is used only after the lead core has been seated conventionally. The seated core and jacket is then reversed, with the internal punch being changed to the Saber Tooth, and pushed open end first into the die. Sufficient lead must be left to cushion and support the teeth, and the punch must be a very close fit to the die bore, to prevent breaking the sharp, thin teeth. The resulting bullet tends to open more quickly and evenly.
	PUNCH-S is a general punch type for the -S series of dies, which includes external punches, internal punches, and drawing punches (which fit directly in the press ram). External punches include the core swage external, and various end-shapes and diameters of core seating punches which fit either the ID of a jacket or the ID of the die. All external punches for swage dies fit into the floating punch holder, in the head of the press, and are retained by a bushing in the punch holder. Internal punches drop into the press ram, and do not come out of the die during operation. The length of the punch head determines how far the punch drops into the ram, and thus sets the position of the other end of the punch within the die. Longer and heavier bullets use shorter punch heads. Punches for drawing jackets or bullets fit into the press ram, and push the component through a draw die that fits the press head (instead of the usual punch holder).
	PUNCH-SA Adjustable Length (core seating or tubing end rounding), for tubing or jackets under 0.5-inch OD. This -S type adjustable punch has a micrometer-like barrel which adjusts on screw threads relative to the central portion, moving the shoulder to the desired position for a given length of tubing or jacket. In rebated boattail core seating, soft or thin jacket materials may tend to extrude forward and lengthen the jacket, taking material from the base section. This may be so severe that the jacket separates. However, even if it is not, the adjustable shoulder can be set to prevent random lengthening of the jacket because of the force of the lead trying to push forward. Adjustable shouldered punches are economical when three or more different jacket lengths may be desired, as each length would otherwise require a separate fixed shoulder length punch.
	PUNCH-SL Adjustable Length (core seating or tubing end rounding), for Large diameter tubing, 1/2-inch OD. Similar to the PUNCH-SA in concept, the larger size components require a different internal construction. This -S type adjustable punch has a micrometer-like barrel which adjusts on screw threads relative to the central portion, moving the shoulder to the desired position for a given length of tubing or jacket. In rebated boattail core seating, soft or thin jacket materials may tend to extrude forward and lengthen the jacket, taking material from the base section. This may be so severe that the jacket separates. However, even if it is not, the adjustable shoulder can be set to prevent random lengthening of the jacket because of the force of the lead trying to push forward. Adjustable shouldered punches are economical when three or more different jacket lengths may be desired, as each length would otherwise require a separate fixed shoulder length punch.
	PUNCH-SA Adjustable Length internal punch can be made for any die, but generally is used with a point forming die (to seal the end of the cavity for use with lead tip or all-lead bullets). The purpose of the adjustable length section is to position the end of the punch or ejection pin exactly at the end of the bullet shaped cavity so the punch seals pressure at the tip of the cavity. This prevents lead from extruding up the ejection pin hole, and allows higher pressure to be used for extrusion in custom weight-adjusting point form dies.
	PUNCH-SF Extra long funnel punch, for use with powdered metals and the Corbin FUNNEL-S precision funnel, helps you seat the powdered material into a jacket. Powder is loosely packed by its own weight, and takes up considerably more space before being compressed by seating. In fact, it takes up so much room that it won't all fit into the jacket in most cases. A normal core seating punch would simply push through the powder, blowing powder past it until it finally reached the jacket. A full die bore diameter seating punch would compress the powder to the edge of the jacket but couldn't enter the jacket. The funnel is made with a precision spout, which exactly matches the jacket wall thickness. The spouts are replaceable, and the funnel body is universal for all jackets and calibers. An extra long core seating punch pushes the column of powder through the funnel and down into the jacket without loss.
	PUNCH-SX is a special kind of custom -S punch (could be specified as a PUNCH-HC, external, core seat or core swage, X-style or cruciform) made either to fit a core swage, or a core seat die, and to put a deep X-cut into the lead core. When used with a core swage die, the x-cut core is coated or filled with lubricant or a powdered filler to prevent the cuts from closing entirely in the core seating operation. When used with a core seating die, the core is normally seated first with a regular flat end or hollow point core seat punch, and then the X is pressed into the core. The purpose is to help the bullet expand evenly into four "petals" as the jacket ruptures and expands on impact.
	PUNCH-SS is a special kind of custom -S punch (could be specified as a PUNCH-SC, internal, core seat, Saber Tooth or cruciform) made to fit a core seat die, and to put a a series of six notched in the jacket end. The Saber Tooth design is used only after the lead core has been seated conventionally. The seated core and jacket is then reversed, with the internal punch being changed to the Saber Tooth, and pushed open end first into the die. Sufficient lead must be left to cushion and support the teeth, and the punch must be a very close fit to the die bore, to prevent breaking the sharp, thin teeth. The resulting bullet tends to open more quickly and evenly.
	PUNCH-S Internal Core Seat, Flat Base (Int CS-FB) is the general description of the punch that stays inside the core seating die and ejects the components on the down stroke of the press. The internal core seater can also have a cup base shape (slight dome), dish base (slight curve), hollow base (conical projection), or Base Guard(TM) base (small depression in center). The internal core seater punch looks very much like the internal core swage punch, but is larger in diameter. The punch end opposite the working face is called the "head". Oddly enough, the head also has a "tail" which is the reduced portion at the very end. The length of this reduced portion determines the position of the punch face within the die at the top of the swaging stroke, which in turn controls how long or heavy a bullet will fit into the die. Shorter heads (longer tails) mean heavier bullets can be made. Very light bullets may require a longer head (shorter tail) to hold the punch closer to the die mouth.
	PUNCH-S Internal Point Form is also called the "ejection" punch (Int.PF). It consists of a long single diameter punch head with a hardened spring steel ejection pin secured to one end. A hole runs through the head of the punch. The stop pin that is located in the front of the CSP-1 press goes through this hole, and secures the punch to the frame of the press. With the punch fastened to the press frame, the die moves up with the ram and the punch is retracted from the die cavity. This keeps the punch from being trapped in the end of the bullet jacket when the ogive is formed. Earlier punches for the -M type die used a slot instead of a hole, and a shorter stop pin. Both kinds can be used in the current -S presses. Ejection pin wires are available for replacement in packages of 5 wires. Diameter depends on caliber and ogive, but is marked on the mouth of the swage die.
	PUNCH-R is a general catalog number for standard punches that fit reloading press dies, including draw dies for jackets and bullets, Pro-Swage dies, and other -R type swage dies. External punches have a button-type head that slips into the slotted press ram, like a shell holder. Internal punches have a cylindrical head that keeps them from dropping out of the die. Swage dies for reloading presses screw into the 7/8-14 threaded head of the press, as do draw dies. The -R dies are further described by their caliber or diameter, the die into which they fit, and any specific shape such as "HP" for hollow point, or "CB" for cup base. (See terminology page for details.)
2004: Corbin Redesigns -S External Punch The External Punch for Corbin type -M dies (fits S-press or the discontinued Silver Press) and type -S dies (fits S-press) has been redesigned to eliminate the separate spacer ring. The new punches have a head length that is twice as long as the original, which takes exactly the same space as the original punch head and spacer ring. The new punches therefore interchange with the old ones. The only difference is that the spacer ring (or ring bushing as it was also called) is no longer needed for the new punches. You can use either the old style, with ring, or the new style, without ring, in the same dies and with the same punch holder. Both work equally well. Background: An "external" punch is one which fits into a floating punch holder in the press head. An "internal" punch fits inside the die and press ram, and is used to eject the bullet on the down stroke of the press. External punches push the bullet components into the die mouth. The original type -M and type -S die sets all used external punches that were held in the punch holder by a threaded, hexagonal-head bushing, which in turn pushed against a spacer ring or bushing around the punch. This spacer ring pushed in turn on the bottom of the punch head, holding the punch head against the end of the hole in the punch holder. The purpose of using both a threaded hex bushing and a spacer ring bushing to hold the punch was to allow the punch to move slightly, or "float", when pressure was applied. This kept the punch aligned with the die bore in spite of slight errors of alignment in the press itself. As the years have gone by and better techniques, machinery, jigs, and experience applied to making Corbin presses, it has become less and less important to provide so much "float" in the punch alignment system. The precision of the presses today is several orders of magnitude better than the original production. Thirty years of experience in building presses has brought about significant improvements in their alignment. Today, the bushing system has outlived its original purpose. There is no need for more than a few thousandths of "float" to allow for possible self-alignment of the punch and die. By eliminating the bushing and making the head itself longer by the same amount, it is possible to hold the punch more precisely while honing, lapping, and doing other finish work on the "business" end of the punch. The ring was one more part to lose, even for experienced bullet makers. Beginners sometimes put the ring in the punch holder behind the punch head, which allowed the punch to smash the ring into the punch holder and damage both parts. And finally, a hardened steel ring adds unnecessary cost to the punch assembly (for .40 caliber and up, as the hex bushing and ring bushing were fastened to them with a removable punch head because the standard bushings that come with the punch holder would not slip over a punch that large). BENEFITS: Less parts to assemble when changing punches. No chance of incorrect assembly or damage to holder. More precise holding during production provides higher accuracy. Fewer parts means holding the line on future prices. Less assembly work on large caliber punches means faster delivery. Since there is no disadvantage to the user, and five advantages, it was not difficult to make the decision to change punch designs. The only disadvantages are in making the transition from old literature, books and publications which show the use of the spacer ring, to eventual new instructions and illustrations that do not show it, and in the possibility that someone who is used to the old design or reads the old published literature will be confused by the lack of a ring and longer head on the new punches. Informational notes will be sent with all new requests for information, all book packages and packaged sets of dies to correct the existing published instructions, until such time as the last of those publications are replaced. At that time a historical note about the earlier version, as compared to current version of the punch and punch holder assembly, will be included in the books, for those who acquire used equipment of the old style and need to understand the purpose of the ring spacer. The new punch design is used WITHOUT a spacer ring. That is the ONLY difference in its use. It is fully interchangeable with the original punch in every other way, fits the same dies and presses and punch holders so long as the ring is not used.
Corbin Manufacturing & Supply, Inc. PO Box 2659 White City, OR 97503 USA Phone 9am-5pm Mon-Thurs: 541-826-5211 Fax 24-hrs: 541-826-8669 Website: http://www.swage.com E-mail: sales@corbins.com

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2004: Corbin Redesigns -S External Punch