Brasso. You can't do a fast reload with a #1 from the shoulder. It's also a bitch from the sit unless you have one of those shellholder that fit around the butt. Al Miller wrote an article on "Speedloading the Single Shot Rifle", I believe it was called in Rifle Magazine. Anyway, he said as the rifle recoils, pull the lever down, remove the rifle from your shoulder, holding the rifle with the right hand, bring the thumb of the left hand over the breech, covering it, while the left hand takes over holding the rifle. Take a cartridge from the holder, (using your pocket is a no no.) with the right hand holding it between the thumb and forefinger. ( You can use those plastic holders that come with Federal ammo or one of those elastic shell holders that fit on the stock. Leave an empty space betweem each round to make it easier to grasp the next round. I think the elastic models work best if you're shooting from the sitting position.) Do not look at the breech. Keep looking at your game. Your right hand holding the shell will automatically find the thumb covering the breech. As the thumb feels the nose of the round start to make contact, move it out of the way and drop the round into the chamber. That's right drop it. If it is a new factory round, or a properly full length resized handload, the round should just drop right on into the chamber. (Neck sizing doesn't go here. Too much chance of the round not fully chambering.) Close the breech, bring the rifle to your shoulder, aim and fire the shot. It's a lot easier than it sounds. If I could personally demonstrate it, you'd see what I mean. Five minutes slow practice and you'll have the motions down pat. Five more minutes and you'll be doing it like a pro. FWIW, it's not too hard to stay up with the average bolt action shooter taking "AIMED" shots. Of course, a seasoned target shooter used to shooting rapid fire is something else, but that doesn't count.
I've been shooting, collecting and hunting with Ruger #1 rifles since 1975, mostly from the bench, but starting about a month from whatever big game season I've drawn tags for, I start the rapid reloading practice, both at home with dummy rounds and at the range with live ammo the last two weeks prior to the season.
BTW. This stuff that Tom Selleck did in Quigley Down Under with the shells between his fingers will work in the short run, but try holding any rifle you have now with two or three rounds tucked between the fingers of the left hand while hanging on to the forearm and see just how long it takes for your fingers to protest loudly. There ain't much padding there folks. It's also a slower method of reloading the rifle.
The methods described will also work with the Browning single shots.
Paul B.