High cotton content, Homer - long fibres. On the other hand target paper has very short fibers, and that's why you don't get long tears with slow moving bullets, but nice round holes.

Most printer/typewriting paper has high cotton content and longer fibers, hense it tears more easily in one directions than the other.

Paper has a grain structure, just like a tree. It will tear/break jagged and crooked against the grain, whereas the tear or split will be with the grain.

The directions on paper patching usually say to tear the paper across a couple corners. One attempt will tear across the corner and the other will rip the length of the paper. The length rip shows the direction of the fibers in the paper. It always (I think) runs one end to the other, or is it across? (Mine runs lengthwise.)

The long part of the paper patch should be 'with' the grain, so as it is wrapped around the bullet, the length of the fibers go around it, giving strength to the patch.

Note there are 4 schools of thought here - some don't care which way the grain runs, others have the grain running around the bullet as described and others yet want the grain to run vertically. The 4th, take great pains to have th grain run parallel with the rifling at it's rate of twist.

I would expect the grain running around the circumference of the bullet would give the highest paper strength, while the paper running with the rifling angle, would be the weakest and most likely to be cut by the rifling, and fall of in strips, which most people want.

Oh yeah - another point, the longer the fibers and higher the cotton content, the more shrinkage the paper does as it dries, making it tighter to the bullet. This is a good thing.

Yet another point, some make the ends square, other on an angle. Some wrapp the angle with the rifling, others across it.

Best advice is to get "The Paper Jacket" by Paul Mathews. It's a good one.

Lots of experimenting, A?