I use a Cap-Chur long barrel pistol, and like it. Not as bulky as a rifle, easier to carry along, particularly in the tractor cab. I feed in winter by unrolling my bales across the pastures. Cattle are all lined up single file pretty much along that swath. When I get done unrolling, I just drive along the line-up, stick my dart gun out the window and treat the one(s) that I need to... very simple and easy, and no rodeoing at all.
As for which meds work best, that's mostly a function of "thin vs. thick" solutions (thick doesn't "flow" out of the dart as easily or quickly, ...but if the dart stays in for the duration, the somewhat thicker formulations do still work ... think LA200 vs. Draxxin, for example). Having your med at room temp vs. frig temp is probably helpful. The biggest "concern" is the recommended dosage.... once an animal gets up over 1000#, if the med is calling for more than 1cc/100#, you're likely going to need a couple of darts. Biggest ones are 12.5cc..., and you usually don't want to inject any more than that in one site anyway. The "low dose meds" typically are the more expensive ones per cc... and if a dart happens to "bounce off", the meds are dispensed from the dart regardless... so that could potentially be a $50 shot wasted. Practice with your practice dart first, on an archery target or something similar in density to the animal... learn how your gun reacts to varying conditions (cold temps vs. warm, etc.), so you can adjust your shooting accordingly. Heavier darts (larger with more meds in them) very definitely and automatically become challenging... don't fly as well to start with, take alot more energy to propel properly, will have a quicker fall in the trajectory so you have to compensate, etc. CO2 cartridges are cheap compared to wasted meds.
