Gad Custom Cartridges sells hollowbased .41 Colt bullets for $10 per 10, or you can buy 100 heel-based bullets of 200 grs. for $7. Either is a bargain.
You'll have to trim cases back if you use heeled bullets.
I cast heeled bullets for the .32 Long Colt, so I'm familiar with the peculiarities of using heeled bullets.
The classic book, "US Cartridges & Their Handguns" by Charles A. Suydam shows the following measurements, taken from vintage cartridges, for the .41 Short Colt.
Bullet: 160(?) grain blunt-nose.
Powder: 15(?) grains of black powder. Grade not mentioned but I'd suggest you use FFFG.
Case rim diameter: .429 to .434 inch. Early cases were .457 to .470 inch.
Case head (forward of rim): .405 to .408 inch.
Case mouth, just below the crimp: .405 to .408 inch.
Bullet, maximum diameter ahead of case: .404 to .413 inch.
Case length (no bullet seated): .771 to .785 inch. Early cases ran .631 to .633 inch.
Overall cartridge length (after heeled bullet seated): 1.168 to 1.218 inch. Early ammo ran 1.101 to 1.133 inch.
As you can see, there is much disparity in some measurements. When these cartridges were made, there was no standardization; factories made what they figured worked. These figures will guide you, though.
As for bullet lubricant with black powder, use what the factories used. I found this recipe years ago in a 1943 American Rifleman magazine, listed as what the factories used years before with heeled bullets.
I used this recipe, but used very specific ingredients in the same proportions. The old article was more general about ingredients.
The following recipe was named after me years ago, as "Gatofeo No. 1 Bullet Lubricant." It's the best black powder bullet, patch and wad lubricant I've found.
The Gatofeo No. 1 Bullet Lubricant recipe is:
1 part canning paraffin, such as that used to seal jars of preserves.
1 part mutton tallow (sold by Dixie Gun Works).
1/2 part beeswax
All amounts are by weight. I typically make a batch of 200/200/100 grams in a widemouth Mason jar, immsersed in a few inches of boiling water for a double-boiler effect. This is the safest way to melt greases and waxes.
Once all ingredients are melted, stir well with a stick or disposable chopstick. Allow to harden at room temperature.
Note: Do NOT substitute the above specific ingredients. Others and I have, and it results in an inferior product. You MUST use mutton tallow, canning paraffin and real beeswax to get this lubricant's benefits.
After you've loaded your cartridges with powder, and seated the heeled bullet down to the stepped-up bullet diameter, you can use a cheap wire stripper to gently crimp the case into the bullet.
A rat-tailed file will remove the sharpness from the edges of the wire stripper, so you don't cut or dent the brass case too much.
After crimping the case into the bullet, turn the entire cartridge upside down and hold the bullet in melted lubricant for a moment. Just the bullet part, stopping where the lubricant meets the brass case.
If the lubricant is hot enough, you'll see a ring of tension form around the bullet, because the bullet is colder than the lubricant.
After a moment, that ring of tension will disappear when the bullet reaches bullet lubricant temperature. That's the moment to remove the cartridge. This will leave an even coat of lubricant on the bullet.
Stand the cartridge upright on a sheet of wax paper and allow the lubricant to cool and cure overnight.
If you remove the cartridge before that ring of tension snaps away, you'll get a big gob of lubricant on the bullet. If that happens, just return the bullet to the hot lubricant and wait for the ring of tension to disappear.
Do NOT put ammo with outside lubricated bullets back into their paper boxes. Instead, place the cartridges into plastic boxes with separated dividers. I think a box made for .41 Magnum or .44 Special would work fine.
The plastic will keep dust and dirt off the lubricant and won't absorb the lubricant like paper.
It's helpful to have two boxes for each group of ammo. One box to carry it to the range, and the other to hold the fired cases. That way, you'll avoid cross-contamination of black powder fouling in the box that carries the clean, lubricated ammo.
When my plastic boxes get too gunky, turn them upside down in the dishwasher. All the old grease and black powder foulilng are cleaned out, along with the dishes.
Because of the variance in manufacturing measurements in old guns like yours, I'd suggest you make one trial cartridge to ensure it will chamber in all chambers. The bullet may be too big to fit your chambers. Making a dummy round will also be useful for display, and for setting up your reloading dies.
Of course, don't put a primer or powder in your dummy case.
You may very well find that heeled bullets are more accurate than hollowbased bullets, which rely upon the pressure of the gases to bump them up to diameter. Heeled bullets begin at larger diameter, so they'll usually fill the rifling grooves well.
I've learned a great deal firing my Marlin 1892 rifle with heeled bullets. I hope this information helps you.
