Jacklegs (or airlegs), stopers, and sinkers are forms of top-hammer handheld drills that are usually powered by compressed air for drilling short, small diameter holes in rock. Holes are generally 1-1/4 to 1-3/4 diameter. Air consumption is typically 150-200 cfm compressed air at 90 psi. The hammering provides 2000-2500 blows/minute. 
Hand-held Stoper Drill Photo: Atlas Copco |
Jackleg drill Photo: Atlas Copco | |
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