WO1995022737A1

WO1995022737A1 - Primer pocket sleeve

Info

Publication number: WO1995022737A1
Application number: PCT/US1995/001842
Authority: WO
Inventors: Van E. Scott
Original assignee: Individual
Current assignee: Individual
Priority date: 1994-02-17
Filing date: 1995-02-14
Publication date: 1995-08-24
Anticipated expiration: 1996-08-17
Also published as: AU1918495A

Abstract

A primer assembly (28) for mounting within an ammunition casing (14). The primer assembly (28) includes a housing (36) having a base (38) and walls (40) defining an inner chamber (42) with a charge (44) mounted within the inner chamber (42). The primer (28) has a cap (50) closing the inner chamber, with the cap having at least one flash hole to communicate the primer flash into the shell or cartridge casing (14). The primer assembly (28) prevents the residue produced by the primer flash from depositing within the primer pocket (26). In the preferred embodiment, the cap (50) is cup shaped and fits over a standard primer housing.

Description

PRIMER POCKET SLEEVE

BACKGROUND

The present invention relates generally to munitions and more particularly to the reloading of ammunition casings, such as, for example, metallic cartridges.

It is common for people who shoot a lot and for those who shoot competitively to reload their own ammunition. Reloading the ammunition reduces cost, and for those who shoot competitively, it provides better control over the accuracy of the ammunition.

This invention relates to an improved primer system for metallic cartridge reloading. Metallic cartridge reloading is a multiple-stepped process: (1) once fired, metallic cartridge cases are cleaned and inspected; the cartridge cases are cleaned by machine and then inspected by hand; (2) the cartridge cases are resized and deprimed using a reloading press and resizing die; (3) the primer pocket is cleaned; this is done by hand, using a primer pocket cleaner; (4) the cartridge cases are reprimed with new primers; this is done using new primers and a reloading press; (5) the cartridge case mouth is expanded; this is done with an expanding die and a reloading press; (6) the cartridge cases are charged (that is, powder is added to the cartridge cases); this is done with a powder measure; and (7) the bullets are seated in the cartridge cases; this is done with the reloading press and a bullet seating die.

All the above steps can all be performed very rapidly, especially on modern progressive reloading presses, except for primer pocket cleaning, which is done by hand. In a spent casing, the primer pocket is coated with residue from the powder flash created by the primer. A small brush is used to clean the primer pocket. The brush is inserted and rotated repeatedly until the residue is removed. In fact, primer pocket cleaning is so tedious and time consuming, that it is often skipped; which can lead to improper primer seating (because the new prime must be placed over the residue of the old primer), which can cause misfires and incomplete powder burning and can be dangerous. BRIEF SUMMARY OF THE INVENTION

The present invention overcomes the above problems in reloading cartridges by providing an easily removable primer pocket liner, which prevents the deposit of residue in the primer pocket. The residue is contained within the liner; and when the liner is removed from the cartridge, the residue remains in the liner and is removed, as well.

The new primer system eliminates the need for primer pocket cleaning and therefore greatly facilitates cartridge reloading. This new primer system consists of a regular Boxer or Berdan-type primer placed inside of a primer pocket liner. The primer pocket liner prevents the primer pocket from being soiled during cartridge firing, and since the primer and primer pocket liner are both removed during depriming, a new primer and primer pocket liner can be placed without the tedious and time-consuming step of primer pocket cleaning. Cartridge cases can be easily modified to allow the use of the new primer systems with exiting reloading dies and presses. The new primer systems can be made to fit into exiting primer pockets. The cartridge cases can be modified to be deprimed using exiting, resizing, and depriming dies by simply widening the primer pocket flash hole which will not increase cartridge pressure during firing because the primer pocket liner has a flash hole which is correctly sized. The resizing and depriming dies of exiting reloading sets can be easily modified to use the new primer systems by simply widening the decapping pin.

The liner of the present invention is used in a typical cartridge. As with all cartridges, the cartridge has a casing which has a midsection and opposed first and second ends defining an interior therebetween. The first end is open for receipt of powder and a projectile. In the case of a shotgun shell, the projectile can take the form of a number of pellets. The second end is generally closed and has a primer pocket formed therein.

The primer pocket projects from the second end in the direction of the first end and is defined by an interior wall and a base. The base has at least one flash hole for communication of the flash created by the primer to the interior of the casing. As is typical, the primer is inserted into the primer pocket usually in a press fit manner. When hit by the hammer of a weapon, the primer creates a flash that is communicated through the flash hole into the inner chamber of the cartridge to ignite the powder within the cartridge. In the preferred embodiment of the present invention, the primer pocket liner is pressed onto the primer to form a primer unit and is then inserted into the primer pocket to keep the primer pocket free from powder residue. Alternatively, the liner could be press fit into the primer pocket and then the primer press fit into the liner. The liner has a bottom and a wall defining a pocket for receipt of the primer. The bottom of the primer pocket liner has at least one flash hole which communicates with the flash hole in the casing of the cartridge. The bottom is positioned adjacent the base of the primer pocket with the liner wall pressed against the interior wall. In this way, the entire primer pocket is covered by the primer pocket liner.

The primer pocket liner facilitates the reloading process of the cartridge. The primer and the liner unit can be inserted into the primer pocket to prepare the cartridge for firing. The residue produced during firing is trapped within the liner. After firing, the liner and the primer can be removed as a unit from the primer pocket, leaving the primer pocket clean for reloading. To reload, a new primer and liner unit is easily and quickly pressed into the casing.

DESCRIPTION OF THE DRAWINGS

Figure 1 is a perspective view of a cartridge or round of ammunition. Figure 2 is a partial, exploded view of the cartridge and of the present invention.

Figure 3 is a partial cutaway view of the cartridge of figure 1.

DETAILED DESCRD7TION

With reference to figure 1, a bullet or cartridge 10 is generally illustrated.

Cartridge 10 includes a projectile 12, for example a bullet, and a casing 14. The casing 14 has a body portion 16 having a top 18 for receipt of the bullet 12 and a generally closed bottom 20. The body 16 defines an interior chamber 22 that receives an accelerant, such as gun powder, and wadding.

With reference to Figures 2, the bottom 20 of the casing 14 is illustrated in a partial, exploded view and a cutaway view. The exterior of the bottom 20 includes a rim 24 that is separated from the body 16 by a groove 27. It should be understood by those of ordinary skill in the art that the rim 24 may vary depending upon the type of cartridge. The bottom includes a primer pocket 26 for receipt of a primer 28. The primer pocket is recessed into the casing 14 and has a base 30 and inner wall 32. A flash hole 34 is formed in the base 30 to communicate the flash created by the primer when the primer is struck by the hammer of a weapon. The cartridge 10 that is illustrated is called a Boxer-type primer, since it has only one flash hole 34 generally centered in the base 30 of the primer pocket 26. It should be understood that other types of primer would benefit from the present invention, such as for example, a primer generally known as a Berdan primer, which has more than one flash hole 34.

The primer 28 includes a housing 36 that is generally cup-shaped and includes a bottom 38 and a wall 40 defining an inner chamber 42. The inner chamber 42 is packed with a charge 44, a foil layer 46, and an anvil 48. When the primer 28 is struck by the hammer of a weapon, the charge 44 is ignited and the flash created travels through the flash hole 34 and ignites the charge 49 in the casing 14. The primer 28 is generally configured to tightly fit into the primer pocket 26 so that the flash created by the primer 28 and the gas created upon the ignition of the accelerant is contained within the cartridge 10 and does not escape around the primer. In a typical cartridge, the flash created by the primer 28 leaves residue in the primer pocket 26 that must be removed when the cartridge is reloaded. If the primer pocket is not thoroughly cleaned, the cartridge will not function properly. To prevent residue from forming in the primer pocket 26, a liner 50 is used to line the primer pocket 26. The liner 50 is generally cup-shaped, including a base 52 and a wall 54, to define an inner chamber 56. The diameter of the inner chamber 56 is equal to or slightly less than the outer diameter of the primer 28 so that the primer 28 can fit snugly within inner chamber 56. The outer diameter of the liner 50 is equal to or slightly larger than the inner diameter of the primer pocket 26 so that the liner 50 can be press fit into the primer pocket 26. In this way, the gas created within the cartridge 10 cannot escape, except out of the end 18 as the bullet 12 is ejected. The liner includes a flash hole 58 that is in communication with the flash hole 34. It should be appreciated that if a Berdan primer were used, there would preferably be more than one flash hole 58 to fully communicate the flash from the primer 28 to the inner chamber 22 of the cartridge 10.

To reload the cartridge 10 after it has been fired, the primer 28 and the liner 50 are pushed out of the spent casing 14. Since the liner captures all of the residue from ignition of the primer 28, the primer pocket 26 is clean and does not have to be cleaned before reloading. To reload, the known reloading steps are used, except that the pocket cleaning step is avoided.

In the prefeπed embodiment, the liner 50 and the primer 28 are integrally formed and inserted into the primer pocket 26 as a single unit. Although the present invention has been described in detail with reference only to the presently preferred embodiment, it will be appreciated by those of ordinary skill in the art that various modifications can be made without departing from the invention. Accordingly, the invention is to be limited only by the following claims.

Claims

What is claimed is:

1. A cartridge comprising: a casing having a midsection and opposed first and second ends defining an interior therebetween, said first end being open for receipt of powder and a projectile, said second end being generally closed with a primer pocket formed therein, said primer pocket projecting from said second end in the direction of said first end and being defined by an interior wall and a base, said base having at least one first flash hole therein for communication between said primer pocket and said interior of said casing; a primer; and a primer pocket liner for insertion into said primer pocket to keep said primer pocket free from powder residue and therein facilitate the reloading process of said cartridge, said primer being mounted within said primer pocket, said primer pocket liner having at least one second flash hole in communication with said first flash hole, said primer pocket liner being positioned adjacent said base and said interior wall; whereby said primer pocket liner and primer can be removably inserted into said primer pocket to prepare said cartridge for firing, said firing producing residue that is trapped within said liner such that after firing said cartridge, said liner and said primer can be removed from said primer pocket leaving said primer pocket clean for reloading and receipt of another liner and primer.

2. The cartridge of Claim 1, wherein said primer is contained within a cup-shaped housing, said cup-shaped housing being adapted to mate with said primer pocket liner to form a primer unit that can be inserted and removed from said primer pocket.

3. The cartridge of Claim 2, wherein said primer unit has a top, bottom and body portion.

4. The cartridge of Claim 3, wherein said primer unit is generally circular in cross-section.

5. The cartridge of Claim 1, wherein said primer pocket liner is generally cup shaped having a bottom and wall, said wall being generally circular in cross-section.

6. The cartridge of Claim 1 , wherein said primer pocket liner is adapted to be press fit within said primer pocket.

7. The cartridge of Claim 2, wherein a cup-shaped housing is press fit within said primer pocket liner.

8. A primer for mounting within the primer pocket of an ammunition casing, said primer comprising: a housing having a base and body defining an inner chamber; a charge mounted within said inner chamber; a cap closing said inner chamber, said cap having at least one flash hole; whereby said primer can be inserted into the primer pocket of said ammunition casing with said cap preventing the residue of said charge from depositing within said primer pocket.

9. The primer of Claim 6, wherein said housing is generally cup shaped with a generally circular base and generally tubular body, said tubular body having a generally circular cross-section.

10. The primer of Claim 6, wherein said cup is generally cup shaped having a generally circular top and with a generally tubular side that is generally circular in cross-section; said flash hole is formed in said circular top.

11. The primer of Claim 6, wherein said housing is generally cup shaped and said cap is generally cup shaped, said housing and cap being sized such that one mates within the other.

12. The primer of Claim 6, wherein said housing and cap form a single unit for insertion and removal from said primer pocket.

13. The cartridge of Claim 8, wherein said cap is adapted to be press fit within said housing.

14. The cartridge of Claim 8, wherein said primer is adapted to be press fit within said primer of said communication casing.

15. A primer unit adapted to be removably mounted within the primer pocket of an ammunition casing; said primer pocket having a base and sidewall and at least one flash hole extending through said base; said primer unit having a body portion with opposed ends closed by a top and bottom, said top having at least one second flash hole communicating with said first flash hole to communicate a flash from said primer unit to said ammunition casing; whereby said primer pocket remains clean after said flash has been communicated to said ammunition casing.

16. The primer unit of Claim 12, wherein said primer unit is defined by first and second cup-shaped members, said cup-shaped members being adapted to mate with one another to form said primer unit.

17. The primer unit of Claim 12, wherein said body portion has a generally circular cross-section.

18. The primer unit of Claim 12, wherein said body portion has an outer diameter which is equal to or slightly greater than the inner diameter of said primer pocket.

19. The primer unit of Claim 13, wherein one of said first and second cup-shaped members has an inner diameter which is equal to or slightly greater than the outer diameter of the other member such that the one member can be press fit into the other member to form said primer unit.