Hi Michael,
Tell us what calibre you are working with and what kind of rifle you have. I shoot several BPC Rifles in different calibres and have excellent rusults.
Rifles I am working with are:
Shiloh LRE .45 X 2 7/8" (.45-110)
Browning Creedmore .45 X 2 4/10" (.45-90)
Original Remington Rolling Block .45 2 4/10"
Shiloh #1 Sporter 32" .45 X 2 1/10" (.45-70)
Assuming you already have a basic knowledge of handloading the following will get you started with BPC.
To start with, your cases should all be uniform and full length sized. After you have fire formed them in your chamber, you may be able to skip sizing your brass. Either way, sized or unsized, just lightly bell the mouth of your cases in the expander die to accept the bullet.
Primers: Most have excellent luck with Fed. 215, Fed. 215M, or Winchester (white box) LR. primers. Others work well but these seem to be the most common among BPC shooters.
Goex powder will perform for most people with a minimum amount of headache. Swiss powder is EXPEN$IVE but of excellent quality. It is also hotter than Goex and therefore produces highter velocities. Some shooters weigh each charge and others use a volume powder measure to throw their powder charges. Either way works, just pick one and stay constant in your methods. Goex likes a good bit of compression, around .200" - .300" or more depending on case capacity. Powder should be compressed after being slowly poured down a drop tube into the case and a over powder wad having been placed on top of the powder charge. Compression should NEVER be done with the bullet as in seating the bullet. Always use a compression die or compression plug otherwise your bullet WILL be deformed and quite often the resulting cartridge will be impossible to chamber.
Over powder wads may be punched from a variety of materials but most shooters, especially beginners will find that .030" or .060" thick wads punched from vegetable fiber gasket material work well.
For best performance, bullets should be hand cast by the user. An alloy of 20:1 (lead to tin) is good in most rifles although some prefer a softer bullet of 30:1. I would say a 20:1 bullet is a good place to start.
A good BLACK POWDER bullet lube is essential to keeping the fouling soft in your bore. For commercial lubes, SPG works well as does Black Magic. Home brewed lubes are much more cost effective and can equal or better the performance of the commercial lubes in most cases. Consult with experianced shooters to see what works well in your climate. Pan lubing well cast bullets is probably the easiest way to lube your bullets although many use a lubrisizer to accomplish this task.
Once you have your cases charged with powder and wad under the appropriate amount of compression, you may seat your bullets by hand or using your press and seating die. Just be careful not to deform the bullet if using your press. If you have adequate neck tension on your bullets you do not need to crimp. If bullets are loose such as may be the case if you are loading fire formed cases without sizing, you can apply a light crimp in your seating die. Some shooters use a pseudo taper crimp by taking the decapping stem out of their sizing die and setting it up so that a fully loaded cartridge wil be slightly and gently squeezed to where the bullet is under suitable tension in the case to keep from falling out.
The key to accuracy is CONSISTANCY in your ammunition.