Gun barrel assembly
AssigneeBenelli Armi S.P.A.
InventorLuigi Moretti
Life of this patent
Estimating the term…
Abstract
A smooth-bore barrel assembly including a first segment that extends downstream of a powder chamber, a bore followed by a segment having an increased diameter, and a final choke constituted by a first final portion and by a second final portion; the barrel is characterized in that the first segment has a divergent-convergent configuration, constituted by a divergent portion and by a convergent portion, or a solely convergent or solely divergent configuration. Advantageously, the barrel assembly can be provided in a modular form and includes three basic components: a barrel body, an extension, an inner choke member and/or an outer choke member.
Claims12
A gun barrel assembly comprising a first segment that extends downstream of a powder chamber, a bore followed by a second segment having an increased diameter, and a final choke constituted by a first final portion and by a second final portion;
- said first segment having a divergent-convergent configuration, constituted by a divergent portion and by a convergent portion, wherein an internal profile of said barrel is defined by means of a mathematical formula that describes the internal profile along the entire length of said barrel, from said chamber to said muzzle;
- said formula containing only the diameters and the length of said chamber, defined by chamber parameters (D, H and L) and by additional parameters (ε0, ε1, β0, β1, γ0, γ1, ρ):
- f
-
- (
- x
- )
- =
- {
- D
- -
- x
- L
- ·
- (
- D
- -
- H
- )
- 0
- ≤
- x
- ≤
- L
- ε
- 0
-
- H
-
- (
- e
- 0
- -
- x
- -
- L
- (
- x
- 2
- -
- L
- )
-
- (
- e
- 0
- -
- β
- 1
- )
- )
- L
- <
- x
- ≤
- x
- 2
- ε
- 1
-
- H
-
- (
- β
- 1
- ε
- 0
- -
- x
- -
- x
- 2
- (
- x
- 3
- -
- x
- 2
- )
-
- (
- β
- 1
- E
- 0
- -
- β
- 0
- )
- )
- x
- 2
- <
- x
- ≤
- x
- 3
- (
- ε
- 1
-
- β
- 0
- +
- ε
- 0
-
- β
- 1
- -
- ε
- 0
-
- ε
- 1
-
- β
- 1
- )
-
- H
- x
- 3
- <
- x
- ≤
- x
- 4
- (
- ε
- 1
-
- γ
- 0
- +
- γ
- 1
-
- ε
- 0
- -
- ε
- 0
-
- ε
- 1
-
- γ
- 1
- )
-
- H
- x
- 4
- <
- x
- ≤
- x
- 5
- (
- ε
- 1
-
- γ
- 0
- +
- γ
- 1
-
- ε
- 0
- -
- ε
- 0
-
- ε
- 1
-
- γ
- 1
- )
-
- H
- -
- x
- -
- x
- S
- x
- 6
- -
- x
- S
- ·
- x
- 5
- <
- x
- ≤
- x
- 6
- (
- (
- ε
- 1
-
- γ
- 0
- +
- γ
- 1
-
- ε
- 0
- -
- ε
- 0
-
- ε
- 1
-
- γ
- 1
- )
-
- H
- -
- ρ
-
- (
- ε
- 1
-
- β
- 0
- +
- ε
- 0
-
- β
- 1
- -
- ε
- 0
-
- ε
- 1
-
- β
- 1
- )
-
- H
- )
- p
-
- (
- ε
- 1
-
- β
- 0
- +
- ε
- 0
-
- β
- 1
- -
- ε
- 0
-
- ε
- 1
-
- β
- 1
- )
-
- H
- x
- 6
- <
- x
- ≤
- x
- 7
- wherein:
- D:
- diameter at chamber mouth;
- H:
- diameter at end of chamber;
- L:
- chamber length;
- ε0:
- topological divergence coefficient with a value of “0”;
- ε1:
- topological convergence coefficient with a value of “1”;
- β0:
- convergence coefficient;
- the ratio between the bore diameter (db) and the diameter at end of chamber (H) (convergent and divergent-convergent case);
- β1:
- divergence coefficient;
- the ratio between the bore diameter (db) and the diameter at end of chamber (H) (divergent case);
- β1 is greater than β0;
- γ0:
- expansion coefficient;
- the ratio between the diameter of the second segment having an increased diameter (dob) and the diameter at end of chamber (H) (convergent and divergent-convergent case);
- γ1:
- expansion coefficient;
- the ratio between the diameter of the second segment having an increased diameter (dob) and the diameter at end of chamber (H) (divergent case);
- γ1 is greater than γ0;
- ρ:
- choke coefficient;
- the ratio between the outlet diameter and the bore diameter β0 or β1.
Dependencies are inferred from the claim text.