Medi-Dart needle #6 (MDN6)

Details

Fitment first, because this is the needle buyers get wrong. The #6 is the newest intramuscular needle Medi-Dart makes and it does not work on its own. It has to be run with the half-moon push rod and a wingnut. Fit it to an older dart still carrying the plain push rod and you will not get the ejection the design depends on. With those two parts in place, the #6 gives you the roughest ridge in the range. The number on a Medi-Dart needle only ever describes the ridge, and the rougher it is the better the needle holds while air pressure drives the plunger through the barrel. That grip is what buys the barrel the time it needs on a mature animal that has decided to move off before you are finished. Like the rest of the IM line it discharges through the solid tip, while the Sub-Q needles are the ones with two holes in the side of the shaft. Wingnut size follows the class of cattle rather than the needle: 13 mm (1/2 in) for cows and bulls, 9.5 mm (3/8 in) for younger cattle up to yearlings. The needle itself is reusable, good for roughly thirty injections on the crossbow and roughly fifty on the extension pole syringe, and it takes a file when the point dulls. If you are updating an older crossbow rather than replacing a needle, look at the conversion kits instead, which bundle the needle with both wingnuts. Talk to your veterinarian about what you are administering and follow the label.