Abstract: A device for removing formlockingly anchored dowels including an anchor rod and an expansion sleeve (31) displaceable along the anchor rod, the device including a sleeve-shaped support member (2) having, at one of its ends, a support shoulder, an indexing projection (4) extending beyond the support shoulder (3) and provided with a load application element (5) movable in a tensile operational engagement with the load application element (32) of the dowel sleeve (31); and a through-bore provided with an inner thread for receiving a shaft (7) having an outer thread (8) cooperating with the inner thread of the through-bore (6) to provide for a relative axial displacement of the shaft (7) with respect tot he support member upon rotation of the shaft (7), the shaft (7) having identical coupling elements (11) provided at its opposite longitudinal ends, and an adaptor (12) including an elongate section (13) having at its free end connection element (14) corresponding to the coupling element (11) of the shaft (7) and

Abstract: An apparatus for assembling multiple automotive body styles on a single assembly line. The apparatus includes a workstation with multiple geometry fixtures, at least one geometry fixture for each automotive body style to be processed at the work station. One geometry fixture is at a ready position of the work station to support an automotive component during a processing operation. The geometry fixtures can be exchanged at the ready position so that a production rate of the assembly line can be maintained. The apparatus also includes a lowerator for transferring an automotive component from an overhead transport system to the geometry fixture at the ready position.

Abstract: An unbalance mass at the front side of a single wheel unit, an unbalance mass at the reverse side of the single wheel unit, a phase difference between the unbalance mass at the front side and the unbalance mass at the reverse side of the single wheel unit, a primary component amplitude of radial run-out of the single wheel unit, a phase angle of the primary component of the radial run-out of the single wheel unit, a contribution coefficient in which the radial run-out of the single wheel unit is transmitted to an RFV, an unbalance mass at the front side of a single tire unit, an unbalance mass at the reverse side of the single tire unit, a phase difference between the unbalance mass at the front side and the unbalance mass at the reverse side of the single tire unit, an RFV primary component amplitude of the single tire unit, and a phase angle of the RFV primary component of the single tire unit are measured and the measured values are input.

Abstract: A process for sealing a ceramic filter by infiltrating a metal into an end of the filter. The process includes the steps of contacting the end of a porous ceramic filter with a molten metal, whereby the metal enters into the ceramic matrix to substantially fill the void space. The ceramic filter is cooled to form a filter having a ceramic-metal composite portion. The present invention also provides a filter having an infiltrated metal seal. Methods for joining infiltrated ends are also provided.

Abstract: The present invention concerns a quantitative organic vapor-particle sampler which can efficiently sample both semi-volatile organic gases and particulate components through the use of a unique sorbent resin coating and process.

Abstract: An end cap is supported by a retractable holding mechanism between an edge press and tube end. A pick up mandrel and extender are mounted in the edge press head. The pick up mandrel is extendible from the edge press to contact the end cap. Non-mechanical means on the pick up mandrel secure the cap to the pick up mandrel while the holding mechanism is retracted. The pick up mandrel carries the end cap to the tube end. The extender is collapsed under pressure of the edge press, allowing it to contact the skirt of the cap and press it into the tube end. The pickup mandrel is retracted into the edge press head, releasing its grip on the end cap, and the edge press head and pickup mandrel are retracted for another cycle.

Abstract: Identical ring-shaped metal blanks are machined whereby each blank forms a plurality of identical components. The blanks are first machined on both sides, and then a stack of the blanks is clamped axially adjacent one another on an arbor. Tools machine the blanks for reshaping the blanks. One of the tools is a slitter which makes axial cuts through the stack to separate each blank into a plurality of components distributed around the axis.

Abstract: A wire tensioning apparatus and method tensions one or more wires by moving the tensioning function from a wire module to an apparatus external to the wire module. Externally to the wire module, a wire is attached to a fixed end and a movable end. Tension is placed on the wire, and the tension in the wire or the vibrational frequency of the wire is detected and compared to a desired value. If the tension in, or the vibrational frequency of, the tensioned wire does not correspond to the desired value, the tension is further adjusted until the desired value is met. Once the desired tension or the vibrational frequency is met, the wire is secured in the wire module in order to maintain the achieved tension and/or vibrational frequency.

Abstract: Disc drives are made with an actuator designed with at least one asymmetrical arm having two masses that move out of phase. The arm is modified by removing a portion of the higher-energy (longitudinal) side, the one with the greater total time-averaged strain energy. This modification reduces the phase difference between the first and the second arm, particularly for a relevant frequency range of interest. Disc drives made by this method exhibit a generally reduced out-of-phase motion, enhancing performance during seeking and track following, especially for arms with two heads that interact with surfaces of opposing discs.

Abstract: A thin film magnetic recording a timing based servo pattern is fabricated using a focused ion beam (FIB). The recording head is fabricated by sputtering a magnetically permeable thin film onto a substrate. A gap pattern, preferably a timing based pattern, is defined on the thin film and the FIB cuts a gap through the thin film based on that pattern. Once completed, the recording head is used to write a servo track onto magnetic tape. The timing based servo track then allows for the precise alignment of data read heads based on the positional information obtained by a servo read head which scans the continuously variable servo track.

Abstract: The system includes means for moving a rivet or a collar from a storage bin to an initial position for the respective gripping assemblies. The presence of the rivet and/or collar is recognized as it moves through a feeding mechanism. After the rivet or collar is gripped, they are moved either into an opening in the workpiece, in the case of a rivet, or onto the tail of a lockbolt, in the case of a collar. The gripping assembly is then released from the rivet or the collar, with the gripping means moving back to an initial position. Further operations can then be carried out on the rivet or collar.

Abstract: An integrated circuit (IC) device is mounted onto a printed circuit board (PCB) by inducing a magnetic field of a selected strength at the surface of the PCB to temporarily hold the IC device onto the PCB. The IC device is provided with magnetic material which is attracted by the magnetic field. The magnetic field is maintained while the IC device and PCB are tested, and then subsequently during soldering when the IC device is permanently bonded to the PCB.

Abstract: An apparatus is provided that crimps an electrical wire having a water-proof plug onto a connector terminal in a given positional relationship and can be applied to an automatic assembling operation. In the vicinity of upper crimping members and lower crimping members of the apparatus which crimp an electrical wire having a water-proof plug onto the connector terminal, there are provided a water-proof plug positioning member which has a positioning protuberance used for placing a water-proof plug in a given position with respect to the front end of the connector terminal and a terminal positioning member which is vertically movable and engages with a positioning groove of the connector terminal. The front end face of a water-proof sealing section is brought into contact with the rear surface of a positioning protuberance, thereby placing the water-proof plug in position.

Abstract: The present invention provides a method of forming a forming a solder ball on a portion, e.g., one end, of a contact. In one exemplary embodiment, the contact is a terminal pin which is intended for use in an electrical connector and more particularly, for use in a solder ball grid array (SBGA) connector. Generally and according to one embodiment, the method includes providing the contact along with a solder-holding clip having a body with an opening. The body has a solder-holding conformation adjacent the opening and a solder mass is held by the conformation. The contact is then positioned proximate to the body opening and heat is applied to the solder mass causing the solder to reflow so that the solder flows into a spherical shape. This results in a solder ball being formed on the portion of the contact. Subsequent to forming the solder ball, the solder-holding clip is separated from the contact leaving a contact with a solder ball affixed thereto.

Abstract: A distributed constant filter capable of being connected to a wiring pattern and the like while simultaneously achieving miniaturization, stable performance and assurance of the reliability and a manufacturing method of the distributed constant filter are provided. In a triplate structure band-pass filter, in place of a high impedance pattern which is, in the prior art, formed on the same face as that of a low impedance pattern in an inner layer, conductor patterns extending in the thickness direction of a stacked substrate are formed. Each of the conductor patterns functions as a via pattern connecting the low impedance pattern in the inner layer and a wiring pattern in the surface layer and also functions as a high impedance line. As long as the filtering characteristic is the same, the line overall length (distance in a plane) of the conductor patterns can be made shorter than the conventional line overall length and the area occupied by the conductor patterns can be reduced.

Abstract: A method of constructing a multilayer electric apparatus, comprising the steps of first providing a set of dielectric layers and forming a set of conductive features and at least one fiducial marking, in mutual reference to each other, on a first one of the dielectric layers. Next, the dielectric layers are joined together to form a stack, such that the first of the dielectric layers is interposed depthwise between others of the dielectric layers and the at least one fiducial marking is distinctly observable from outside of the stack. Finally, a via is drilled from the exterior of the stack to one of the conductive features of the first dielectric layer, referencing the drilling to the fiducial marking.

Abstract: A method is described having the steps of providing a surface having a plurality of wire bondable locations; wire bonding a wire to each of the wire bondable locations using a wire capillary tool; controlling the position of the capillary tool with respect to the substrate; after forming a wire bond of the wire to the wire bondable location moving the capillary tool relative to the surface as the capillary tool is moved away from the surface to form a wire having a predetermined shape.

Abstract: Heat exchanger header tanks are constructed from a basic set of components. The basic components are castings and simple formed sheet parts. The components are assembled to produce a heat exchanger tank having a desired size and geometry.

Abstract: Roller covers and methods for manufacturing such roller covers are disclosed. According to one method, a paint carrying medium is secured to a core material to form a composite material having at least one core layer and a paint-carrying layer, wherein the composite material has opposite edges. The opposite edges are positioned adjacent to one another and are secured together. According to an alternative method, a paint-carrying medium having a backing is provided. The backing is treated to an adhering state and is applied to a core while the backing is in the adhering state. According to yet another method, a paint-carrying medium having a backing including opposite edges is provided. The opposite edges are positioned adjacent to one another and are secured to one another. According to an alternative embodiment, a roller cover includes a paint-carrying medium and a core supporting the paint-carrying medium.

Abstract: A crush sleeve has a plurality of protrusions distributed about its inner or outer circumference, usually along its axial midpoint. A two-piece bearing ring is positioned over the crush sleeve with the protrusions between the two portions of the two-piece bearing ring. The two portions of the two-piece bearing ring are forced against the protrusions in opposite axial directions, thereby deforming the protrusions, until a desired clearance results within the bearing. The two-piece bearing ring may be either an inner or outer bearing ring.

Abstract: A grapefruit knife for use in cutting sections of edible fruit from the less desirable membrane and peel is disclosed. The present invention includes a handle having two opposing ends, a single cutting blade attached to one end of the handle, and a scooping blade attached to the other end of the handle. Each of these blades has two cutting edges. On the cutting blade the two cutting edges are aligned serially, in a plane, to cut in the same direction, while on the scooping blade the cutting edges are opposingly arranged.

Abstract: A cutting blade safety cover for covering a rear portion of a cutting blade of a portable trimmer. The safety cover includes a roof plate portion and a skirt portion suspended from the roof plate portion. The roof plate portion is separated at a radially middle location thereof into a radially inner portion and a radially outer portion. The radially inner portion and the radially outer portion are detachably attached to each other so that the radially outer portion is replaceable with another radially outer portion having a dimension suitable for covering a cutting blade of a different dimension.

Abstract: The present invention relates to a media cutting tool for use with a template. The apparatus of the present invention maintains proper alignment with a template through the use of a novel offset, rotating, cutting blade and guards against skipping along the cut as the apparatus is drawn around a template through the use of a novel guide mechanism which engages the template being traced. The present invention also employs a transparent handle for an improved view of the cutting area.

Abstract: A tilt angle sensor is disclosed that is capable of detecting whether a tilt angle of a reference plane exceeds a predetermined value by means of only one threshold value. Although only one threshold value is used, the tilt angle can be measured with respect to either a clockwise or a counterclockwise direction from the untilted state. A pair of differential electrodes electrically independent of each other are formed in a shape symmetric with respect to upper and lower sections of a printed circuit board. A common electrode plate is mounted opposed to the pair of differential electrodes with a predetermined gap therebetween. The pair of differential electrodes and the common electrode is stored in a closed space formed by the printed circuit board and an oil case. A dielectric liquid is filled into the closed space in such a way that the level of the liquid varies according to the tilt of the reference plane.

Abstract: An apparatus and method for securing and aligning level indicators such as bubble vials includes the use of a spring structure with a screw adjuster. In some embodiments, multiple spring structures are positioned perpendicular to one another to allow precise adjustment in different planes. The spring structure is economical to manufacture, and allows accurate adjustment of levels placed in equipment having imprecisely bored holes.

Abstract: A gauge for a coordinate measuring machine has a plurality of balls whose centers are located on at least one line inclined with respect to a reference axis in a virtual reference plane. The gauge is set on a measuring table of the coordinate measuring machine. Orthogonal coordinates in which one of the coordinate axes is identical to the reference axis are set in the virtual reference plane. The coordinates of the center of each ball are measured by the coordinate measuring machine. Thereafter, the gauge is turned and inverted by 180 degrees about the reference axis and is set again on the measuring table. Orthogonal coordinates in which one of the coordinate axes is identical to the reference axis are set in the virtual reference plane. The coordinates of the center of each ball are measured in the same way as above. Thus, measurement errors of the straightness of the machine axes of the coordinate measuring machine and the orthogonality between the machine axes can be easily and precisely evaluated.

Abstract: A cutting template for use in cutting a geometric shape or pattern, such as an oval, of any size, into or out of a selected medium. A preferred embodiment configured according to the invention includes a transparent or translucent sheet with two or more grooves therein that generally define a selected geometric pattern, and additional grooves in the sheet define one or more similar patterns that differ in size, with the several different size patterns being arranged in a nested relationship. The grooves serve as guide channels for a cutting instrument that extends directly through the channels into cutting relation with an underlying medium, thereby eliminating any need for separately tracing the desired pattern onto the medium. Different embodiments of the invention have sets of grooves which define different shapes.

Abstract: In a drying section of a machine for producing a material web such as, in particular, a paper or cardboard web, a pick-up suction roll, in particular a larger pick-up suction roll, is provided between the last pressing nip of a pressing section and a subsequent impingement drying unit, which suction roll removes the material web from a pressing felt guided through the pressing nip or from a transfer belt and transfers it to the impingement drying unit.

Abstract: Method of making safe a heat treatment enclosure operating under a gas atmosphere, the said enclosure comprising a cooling chamber for rapidly cooling a metal strip running from an upstream chamber to a downstream chamber by means of a plurality of guide rollers, wherein said rapid cooling chamber is filled with a controlled atmosphere with a high hydrogen content and said strip is confined within said rapid cooling chamber by means of at least one pressure-balancing duct and of a plurality of gas locks placed between the various chambers, the pressures of the gas atmospheres between the chambers being balanced by means of ducts controlling the flow rates of the gas flowing through the said gas locks.

Abstract: Device and process for removing a fibrous material web from a drying section of a machine for producing and/or refining the fibrous material web and into a catch device. The drying section includes heated drying cylinders, guidance rolls, and at least one drying wire arranged such that the fibrous material web is guided through the drying section over the heated drying cylinders and the guidance rolls at least predominately by the at least one drying wire. The device includes at least one controllable separating device arranged to at least reduce an adhesion force between the fibrous material web and the at least one drying wire.

Abstract: Support is provided to the foot of a shoe wearer by an air cushion that includes a support chamber surrounding a collapsible pump operable by the foot of the wearer for directing compressed air into the support chamber and varying the firmness of the chamber. The support chamber is of a preformed three-dimensional configuration of sufficient rigidity to provide stable support to the foot prior to receiving compressed air from the pump.

Abstract: A perfected insole for footwear of the type formed by a flexible laminate body cut in the form of the interior surface of the sole or base of the footwear. The laminate body corresponds to an end zone which has a modified horizontal direction. The upper face of the laminate body has a central raised zone portion of the same width as the insole. That extends laterally in a longitudinal direction on the interior part of the area of the arch of the foot to the heel part, with the central raised zone covering the tarsus and metatarsus area.

Abstract: A removable insole for insertion into footwear, includes a lower layer made of a viscoelastic gel and including a lower surface, an upper surface, a toe portion, a heel portion and a medial arch portion interconnecting the toe portion and the heel portion, a first recess formed in the lower surface of the toe portion and a second recess formed in the lower surface of the heel portion, each recess having a peripheral side wall and a top wall, a plurality of thin, parallel, spaced apart sinusoidal wave shaped spring walls formed from the viscoelastic gel and connected to the top wall and the peripheral side wall in each recess, and the spring walls having lower edges generally coplanar with a lower surface of the toe portion and heel portion which is in surrounding relation to the respective recess; and a top cover secured to the upper surface of the lower layer.

Abstract: This invention is in the field of snow removal. More particularly, the invention provides a snowplow blade and an attachment apparatus to be secured to the front of a contractors type wheelbarrow and operated manually. Snow removal is facilitated by the ability to add ballast to the wheelbarrow, which preserves momentum, and by the unique design.

Abstract: A rake attachment and a bucket attachment incorporating the same, the rake attachment generally comprising a plate, a plurality of apertures in the plate and a plurality of teeth. The elongate plate has a plurality of mounting holes extending therethrough and a plurality of integrally formed teeth projecting therefrom. The entire rake attachment is formed from a unitary plate of material to provide strength and durability. The rake attachment is designed to be fixed to the bucket attachment of a loader. Different bucket attachments are produced by various manufacturers and each have differently spaced apertures extending through a lower lip of the bucket. The rake attachment features a plurality of holes that can be combined into many different sets, each set corresponding with the spaced apertures of a specific manufacturer's bucket attachment. As such, one rake attachment can be used with a variety of different bucket attachments for loaders.

Abstract: The apparatus for attaching an accessory to an excavator is a device for attaching a grader blade, brush blade, compactor, or other accessory to the bucket of an excavator. The apparatus has a body to which the accessory is attached which has a pair of hooks which slide between adjacent pairs of teeth on an edge of the excavator bucket and a pair of chains attached to the rear of the bucket and tightened by load binders to retain the apparatus on the excavator bucket. The apparatus provides for pivoting the accessory laterally, and may optionally provide for tilting the accessory in a vertical plane.

Abstract: A mast assembly is adapted for attachment to an excavating apparatus such as a loader bucket of a skid steer vehicle such as a BOBCAT. The excavating apparatus includes a rear wall, a pair of side walls, and a bottom. The mast assembly includes a mast, which can be fabricated from any suitable relatively rigid and durable material, such as aluminized steel. The mast includes an upper portion and a lower portion connected by an angled portion angled to maintain the upper portion in an upright vertical position. A laser receiver is secured to the upper portion of the mast with a pair of adjustable securing straps. The laser receiver operates in a known manner to receive laser energy from a laser beacon to facilitate accurate positioning of the excavating apparatus. A first removable securing member, such as a hook arrangement or latch bracket, is affixed to the mast. The hook arrangement can include a pair of hooks which extend through a corresponding number of bores formed in the excavating apparatus.

Abstract: A color-coded semaphore system in which an individual wears a semaphore that signals characteristics and interests for social purposes. Each color indicates a specific quality related to the individual, such as, but not limited to, personality type, marital status, religion, politics, the type of person that the individual is interested in meeting, etc. The semaphores indicate the qualities of the individual wearing the semaphore, but also indicate to others what qualities the individual may be seeking, such as, but not limited to, personality type, marital status, religion, politics, etc. The semaphore system can be implemented using a variety of color-coded items, such as jewelry (e.g. rings, necklace's, pendants, pins, tie tacks, bracelets, body piercing jewelry, etc.), or garments using color-coded insignia. Other alternative embodiments allow multiple semaphores to be worn simultaneously to allow a variety of the individual's interests to be signaled.

Abstract: An illuminated sign designed to be viewed from a horizontal line of sight of an observer, the sign comprising: a frame, a partially transparent face thereon, tubing mounted therein and having an inside radius (r), and a single or plurality of concavely-curved, reflective channels each being substantially semi-cylindrical and having a radius (R), and positioned at a distance (d) from the luminous tubing; wherein the improvement comprises each channel having an angle of wrap (&bgr;) approximately equal to about 70% to about 150% of the value that solves the equation 1 1 sin ⁢ ( β 2 ) + 2 ⁢ ( R r - d r - 1 ) ⁢ cos ⁢ ( β 2 ) = R r .

Abstract: An emergency exit sign includes a support assembly which permits rotation of lighting heads, about an upright axis, through an angle greater than 180°. A freely rotatable joint element is used to maintain the lighting heads, in cooperation with mating facets, in various positions without the need for mechanical fasteners. The lighting heads are also attached to a snap connector which, enables the lighting head to be shifted about an arcuate axis, as well as rotated about a still further axis which is substantially perpendicular to the upright axis.

Abstract: A product is disclosed to assist a vehicle owner and user in properly keeping track of the amount of miles driven in a particular vehicle. The goal of the product is to ensure that regular oil changes will occur approximately every 3,000 miles, which is the usual recommended interval that oil changes occur for most vehicles. The product is a multipage notepad which is preferably one inch tall by one and one-half inches wide, and which can be fastened to an automobile dashboard by means of a mounted Velcro tab, with an accompanying Velcro tab mounted onto the dashboard. The product is designed to provide a user with the ability to perform a quick mathematical calculation in order to determine whether it is presently time to perform an oil change.

Abstract: A patient care and medical alert system for a patient care facility is disclosed which includes a message board adapted and configured to be mounted on a wall associated with a room of the patient care facility. The message board has a front surface defining a permanent message area and a temporary message area. The permanent message area contains indicia identifying the room. A set of message bearing members are provided and each contains distinct indicia relevant to the care of a patient located with the room adjacent the message board. The message bearing members each include structure for effecting the removable attachment thereof to the front surface of the message board within the temporary message area.

Abstract: The present invention is a message display apparatus that is preferably weather resistant. The present invention is comprised of a pair of parallel side frame members attached at their ends to a bottom frame member. The side frame members are also adapted to receive a pair of covers where at least one of the covers is visibly clear. The clear cover allows a message board to be displayed while simultaneously protecting it from poor weather. Additionally, a top frame member is attached to the message board so that it can be easily inserted into and removed from the message display apparatus.

Abstract: A fastening system and method to secure a light panel to the rear of a picture frame through the use of dual locking refittable fasteners in combination with retainers of the frame. The versatile thin illumination assembly system, consisting of the combination of the light panel and mounting system, can be applied to most existing display frames, thus converting a non-illuminated picture frame to an illuminated picture frame. The system when coupled with a frame creates an open backing that maintains the original light panel housing and eliminates heat buildup or dissipation complications often experienced with closed mounting systems. The mounting system and method requires no additional tools for the assembly process, and the resulting frame assembly is thin and easy to assemble.

Abstract: An easel for coupling to the back of a clip frame by one or more clip frame clips that hook around the front of the clip frame and engage in slots in the back of the clip frame, the easel comprising an easel body; and at least one opening defined in the easel, whereby a clip is passed through at least one such opening and engaged in a slot in the back of the clip frame, to hold the easel body relative to the back of the clip frame.

Abstract: A bi-directional album page including two flexible plastic sheets, at least one and preferably both of which are transparent, configured such that photographs of one width may be inserted through side openings and a photograph of a greater width may be inserted through a top opening. The page may include a paper sheet captured between the two plastic sheets.

Abstract: A frame assembly for quickly, easy, and inexpensively framing a work of art without requiring any special tools or skills. The frame assembly includes a transparent protective member and support member. A work of art is positioned between the protective and support members. One or more frame members are then used to secure the protective and support members together. Frame members may be two or three dimensional. Each frame member has a slot defined therein to be slidably displaced over the assembled protective and support members with the work of art disposed therebetween. An internal rib projects outwardly into the slot of the frame member. This rib is received within a corresponding slot defined in at least a portion of the support member. To further ensure that the protective and support members remain secured together, a retaining member, such as a spring clip, leaf clip, or eccentric cam, may be positioned within the slot of the frame member to produce a force against the support member.

Abstract: An adjustable framing system for three-dimensional objects which has a three-dimensional shimming system and an access door in the rear. The access door allows objects to be easily inserted, and then temporarily removed for examination, and subsequently easily replaced. The framing system has a deep compartment for holding publications having a variety of sizes. The framing system is designed to accommodate varying sized publications by using matting in the front of the event programs, and a three-dimensional shimming system which includes vertical and horizontal shimming on the sides of the event program, and thickness shimming on the rear of the event program. An internal wall provides depth for an internal cavity which provides room for publications or other objects that vary in thickness. Separate display compartments may be provided for displaying tickets or descriptive labels for the objects in the frame.

Abstract: A high power bolt action rifle combined with a removable “back up” single shot barrel. The bolt action barrel would preferably be on top of the single shot barrel. This arrangement facilitates with the ease of converting it from hunting dangerous game (incorporating both barrels) to hunting non-dangerous game (removing lower single shot barrel). When hunting dangerous game with this rifle one receives the full benefit of a bolt action, and that of a double rifle. After the bolt action is fired the hunter can decide whether to immediately follow up the shot by firing the single shot barrel or work the bolt and load the bolt action and fire the bolt action barrel again.

Abstract: A system for firing either a first cartridge or a second cartridge from a handgun, the first and second cartridges having dissimilar calibers. The system includes a first barrel removably mounted to the handgun, with the first barrel including a first cartridge chamber sized to permit placement of the first cartridge into the first barrel in a firing position. The first cartridge chamber is sized to prevent placement of the second cartridge into the first cartridge chamber in the firing position. A second barrel is provided, which is interchangeable with the first barrel and which is also removably mounted to the handgun. The second barrel includes a second cartridge chamber sized to permit placement of the second cartridge into the second barrel in a firing position, and the second cartridge chamber is sized to prevent placement of the first cartridge into the second cartridge chamber in the firing position.