I acquired a little .50 caliber Thompson Center White Mountain Carbine recently. It has provided a refreshing break from more modern arms. The defining feature is simplicity!
I don’t lug supporting beanbags to the range with it. With no telescope, “minute of angle” groups aren’t in the cards. Coarse open sights on a 20” barrel mean that getting all those ½” holes touching at 75 feet is enough to raise a smile. I don’t even notice the heavy trigger.
It's the most fun I’ve had since wandering the fields as a boy, toting a single shot .22 and a box of shorts.
Shooting a Muzzleloader
Muzzleloaders are quite a bit different from breechloaders. Here’s my cadence:
Starting a range session, pour about a cc of powder down the bore, with only a potato packing peanut holding it in place. Cap and fire. You want to know that the flash channel is clear of any residual oil before loading a full charge, and ramming a ball home. Dribble in a few grains of 4F with a nipple charger, recap and try again if necessary. Once it lights off, you are good to go. Then:
With the hammer at half cock, pour your propelling charge down the bore. Press a wad into place. I like to use a full ½” thick vegetable wad. Place a patch moistened with 91-99% isopropyl alcohol over this, and push it onto the powder charge. (The hammer is at half cock so that any compressed air can escape.) When the ramrod is withdrawn, the patch will remove a good bit of any previous fouling. Always use a wet one! A dry patch may become stuck, and resist removal.
A patched round ball can then be placed on the muzzle, pressed into place with the short starter, and rammed home. Cap the nipple, and your rifle is ready to fire.
Swabbing the full bore between shots is likely to push powder fouling into the patent breech flash channel, setting the stage for a misfire. Proceeding as above swabs only that part of the bore which receives a fresh ball, leaving the combustion chamber to cake with fouling as it will. It’s usually good for more shots than you will want to shoot, and you can deal with the resulting mess once the fun is over. After your shooting session: swab the entire bore with 91–99% isopropyl alcohol (and I like to put some lanolin into this bottle) until the patches come reasonably clean – it takes 3 or 4. Go home.
Cleaning the Rifle - this is how I do it:
When home, rub down the external metal surfaces with the isopropyl/lanolin mix. Place a small piece of leather over the nipple and lower the hammer to hold it into place. With the rifle vertical in a secure holder, pour several cc of Friendship Speed Juice (equal parts of 91-99% isopropyl alcohol, Murphy’s Oil Soap, and hydrogen peroxide) down the bore. Let the combustion chamber soak while you load some water into a Bissel Steam Shot and plug it in.
Up end the rifle into a waiting container (I use a ceramic vase) and pour the gunk out. Set it into a horizontal cradle, and swab the bore with patches soaked with Speed Juice until they come clean. Run a couple of dry patches, and then remove the nipple. Drop it into a paper cup with enough Speed Juice to cover it, and let it soak. You can retrieve it the next morning (and twirl a toothpick through it). Clean the area around the nipple seat, and hammer face, with the isopropyl/lanolin mix.
By now the Steam Shot should be ready. Don protective gloves, and then blast out the nipple seat and flash channel with live steam, holding your muzzle over the waiting vase. You will see a gush of black muck exit. Replace the rifle into the cradle, and swab with dry patches until all water is gone. The steam will have heated the barrel, so that this won’t take long. Go over the area around the nipple seat, and the hammer face, again. Then replace the nipple with a fresh one (and use anti-seize on the threads!). Snug it into place, but don’t crank it down.
Occlude the fresh nipple with a small piece of leather again, and place the rifle into its vertical holder. Pour several cc of isopropyl/lanolin down the bore. Here, you really do want to have blended in around 10% lanolin, to leave a fine protective film when the alcohol evaporates. After a few moments, pour the excess into your handy vase. Dry the bore with a clean patch or two. The final touch: run a patch saturated with Dexron automatic transmission fluid through the barrel. Your rifle is now ready for storage, until the next time that you want to make smoke! This takes longer to describe than to do.
Now, you must do this without fail, the same day that you shoot. Your rifle won't rust if you do. It surely will if you don't!
Safe Black Powder Loads
Here are Thompson Center recommended loads for the White Mountain Carbine, with pressure data taken from the Black Powder Handbook, 2nd edition. Pressure measurements vary widely between powder brands, rifling twists, and barrel lengths. I have shown the highest pressure that Lyman recorded.
Patched 0.490” Round Ball:
50 grains 2F 6,700 psi
100 grains 2F 9,900 psi
A 3F equivalent: 40 grains, 8,600 psi
If you are forced to use black powder substitutes, please read this first.
Personal Observations
Here’s a light target load, with a patched 0.490” round ball, over a ½” thick vegetable wad.
2.2 cc Schuetzen 3F (32.5 grains) – 918 fps MV in my White Mountain Carbine.
Fouling Control
Black powder leaves around 50% of its weight as fouling, deposited in the rifle bore. This is why swabbing between shots is a necessary annoyance. Old timers used to “duplex” their loads – put a little smokeless in there – to reduce fouling, and allow more shots between swabbing. This has been done for over a century, but does raise safety concerns. Impetuous shooters have been harmed.
I spent several months researching and exploring duplex loads, in search of a clean bore – but unfortunately, any fouling reduction was so scant to as be negligible. This taught me to just accept routine barrel swabbing as part of the muzzle loading experience. You do get used to it.