Straight-Wall Cases and Fillers

[Dan Chamberlain]

I have been researching the issue of using fillers in large capacity straight walled cases when loading moderately light loads.  Everyone talks about using polyester.  No one mentions cotton.  Can anyone tell me why?  I would think a pellet of loose cotton would fill the space and expand to act as a nice filler.  

Any thoughts?

Dan C

[Reed1911]

Cotton has a nasty habit of balling up when it's compressed and refusing to ignight. When it's fluffy it burns really clean, but when you stuff it in a case it creats a ball of junk then usually fouls up the bore pretty bad. Poly, or dacron even when compressed will melt to such a small pellet it becomes a moot issue. Will cotton hurt anything? Probably not, but why take the chance and why spend the extra cleaning time.

[jhalcott]

cotton  can form into balls that wont keep the powder against the primer.It wont compress as much as poly,and MIGHT become a secondary projectile. This could result in a "ringed" chamber. When kapok was all the rage, some guys did not add enough to give a slight compression of the filler. Many guns were damaged by this mistake. Cereal fillers also need some compression to keep them between the powder and bullet. One half grain of poly wadding will keep almost any charge against the primer and usually burns away before exiting the muzzle. It leaves practically no residue,improves internal ballistics and accuracy. I found poly to be the best filler in 45-70 ,30-06 and other large cases when loading lite plinking loads.You may try fooling around with other fillers( I DID) before you come back to poly. That's what makes reloading so much fun!

[Dan Chamberlain]

Thanks guys.

Dan C

[Questor]

Proceed cautiously. I was just rereading some old work by Elmer Keith and he cautioned that using the wrong kind or amount of filler could have disastrous effects on pressure.  I'd look for specific data from the likes of, say, the cast bullet society.