I use a capchur pistol. I've had the rifle, and sold it. I've never had a dart fail. I've been too close once. I've had the gun be just about out of co2 a few times. I have some 10cc darts. I've suspicioned they would fail, just based on volume of meds to deliver. I would also think la300 would be to thick, and too high a dose to use.
We had a Cap-Chur gun when I was in practice. Hated the dad-blasted thing. Only ever used it for tranq'ing cows that folks couldn't catch - 70% of my cattle clients did not have cattle handling facilities - no corral, no chute, no headgate; at most, some might have an old tobacco barn... if they could fool the cows into going in there.
Had way too many instances where I'm certain that it didn't deliver the full dose - or any of it, for that matter.
You couldn't count on it - one cow might be out like a light in 5 minutes and sleep for a day and a half, the next might slow down enough in 30 minutes that if you were real stealthy, you might be able to drop a rope on her - then she was up and on the fight!
Been hearing some reports of cattle showing up at slaughter with medi-dart needles broken off in them. Y'all be careful.
We don't have a Pneu-Dart gun and after me trying to hit bulls with the vet gun for flys I don't think the boss will ever let me have one. Our coming two year old bulls are not small but I managed to hit 4 our of 12 trys. At that point the boss removed the gun from my hand and told me he couldn't afford my help. :nod: