Patent ID: 7654775

Claim:
A device for use in soil nailing comprising: a protective shroud; a breach having a cavity therein; a barrel having an inner tube, a bore and an outer tube extending through said inner tube, and an annular space between said inner and outer tubes, said barrel interconnecting said shroud and said breach; a passageway extending from said annular space into said breach and communicating with said cavity; a source of compressed gas to pressurize said annular space; at least one breach plate attached to said breach, and an aperture formed in said breach plate to receive a soil nail therethrough; said breach having an open end to receive said outer tube of said barrel; wherein said annular space communicates with said passageway through an area of connection at said outer tube and said breach, and said annular space at said area of connection is at least as large as an area of said annular space located distally in said barrel.