US4640724A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Methods of priming explosive devices
Assignee: Eley Ltd
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Filing: 1981-03-20
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Granted: 1987-02-03
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Expires: 2001-03-20
Abstract
Abstract The invention provides a method of priming a blank or bulleted rimfire cartridge comprising the steps of (a) dosing into the rimfire case a quantity of a substantially dry, powdery, relatively insensitive premix comprising, in predetermined proportions, at least two materials that will, in the presence of a liquid reaction medium, react together forming a primary explosive compound, (b) compacting the premix so as substantially to fill the rim of the case therewith, (c) dosing a quantity of the liquid reaction medium into the case so as to cause said materials to react together forming the primary explosive compound and (d) drying the primer. By compacting the premix into the rim before the addition of the liquid reaction medium, the conventional spinning step may be dispensed with, thereby making the priming process safer and more economic.
Inventors
- 👤 George B. Carter
- 👤 Alan P. Manby
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 23:45
CPC Classifications
C; C06; C06C; C06C7/00; C06C7/02; F; F42; F42B; F42B33/00; F42B33/02; F42B33/0207
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
119 words
A method of priming a rimfire cartridge by providing in the rim thereof a quantity of primer comprising a primary explosive compound, said method comprising, in the recited order, the steps of: (a) dosing into the rimfire case a quantity of a substantially dry, powdery, relatively insensitive premix comprising, in predetermined proportions, at least two materials that will, in the presence of a liquid reaction medium, react together forming said primary explosive compound, (b) compacting the premix so as substantially to fill the rim of the case therewith, (c) dosing a quantity of said liquid reaction medium into said case so as to cause said materials to react together forming the primary explosive compound, and (d) drying the primer.
Claim 2
Independent Claim
119 words
A method of priming a rimfire cartridge by providing in the rim thereof a quantity of primer comprising a primary explosive compound, said method comprising, in the recited order, the steps of: (a) dosing into the rimfire case a quantity of a substantially dry, powdery, relatively insensitive premix comprising, in predetermined proportions, at least two materials that will, in the presence of a liquid reaction medium, react together forming said primary explosive compound, (b) compacting the premix so as substantially to fill the rim of the case therewith, (c) dosing a quantity of said liquid reaction medium into said case so as to cause said materials to react together forming the primary explosive compound, and (d) drying the primer.
Claim 3
Dependent Claim
60 words
A method according to claim 1 wherein said quantity of premix is compacted by axially advancing a generally cylindrical punch into the case via its open end and into contact with the premix, the forward end of the punch being so shaped that it forces an amount of said premix into the rim sufficient substantially to fill the rim therewith.
Claim 4
Dependent Claim
32 words
A method according to claim 2 wherein the forward end portion of the punch is right-circular cylindrical, the transition between the cylindrical surface and the end face of said portion being radiused.
Claim 5
Dependent Claim
43 words
A method according to claim 2 wherein said quantity of premix is compacted in two stages, the first stage utilising a punch as specified in claim 3 and the second stage utilising a punch the forward end portion of which is right-circular cylindrical.
Claim 6
Dependent Claim
50 words
A method according to claim 1 wherein, after addition of the liquid reaction medium but before drying of the primer, the interior of the cartridge case is subjected to a partial evacuation/air admission cycle to aid impregnation of substantially the whole of the compacted premix with the liquid reaction medium.
Claim 7
Dependent Claim
55 words
A method according to claim 1 wherein, after addition of the liquid reaction medium but before drying of the primer, a quantity of a liquid medium containing a film-forming material is dosed into the case whereby, upon drying of the primer, a film of said film forming material forms on the surface of said primer.
Claim 8
Dependent Claim
12 words
A method according to claim 6 wherein said film-forming material is shellac.
Claim 9
Dependent Claim
34 words
A method according to claim 1 wherein said liquid reaction medium contains a film-forming material whereby, upon drying of the primer, a film of said film-forming material forms on the surface of said primer.
Claim 10
Dependent Claim
15 words
A method according to claim 8 wherein said film forming material is an acrylic polymer.
Claim 11
Dependent Claim
40 words
A method according to claim 1 wherein said primer is a composition containing said primary explosive compound and one or more other ingredients, the premix containing, in predetermined proportions, said one or more other ingredients in admixture with said materials.
Claim 12
Independent Claim
107 words
A method of priming a rimfire cartridge comprising: dosing into the rimfire case a quantity of a substantially dry, powdery, relatively insensitive premix comprising, in predetermined proportions, at least two materials that will, in the presence of a liquid reaction medium, react together forming said primary explosive compound; then compacting the premix with at least one axially movable punch so as substantially to fill the rim of the case therewith without spinning; then dosing a quantity of said liquid reaction medium into said case so as to cause said materials to react together thereby forming a primary explosive compound in the rim; and then drying the primer.
Claim 13
Independent Claim
107 words
A method of priming a rimfire cartridge comprising: dosing into the rimfire case a quantity of a substantially dry, powdery, relatively insensitive premix comprising, in predetermined proportions, at least two materials that will, in the presence of a liquid reaction medium, react together forming said primary explosive compound; then compacting the premix with at least one axially movable punch so as substantially to fill the rim of the case therewith without spinning; then dosing a quantity of said liquid reaction medium into said case so as to cause said materials to react together thereby forming a primary explosive compound in the rim; and then drying the primer.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-02-02 | 1990-08-04 | 1991-02-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-02-02 | 1994-08-04 | 1995-02-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-02-02 | 1998-08-04 | 1999-02-03 | $7700.00 | Window Closed / Lapsed |