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Case Fillers Keep powder against the primer for higher velocities & consistency

I have answered a number of questions over the years about case fillers, particularly in rifle cases, to keep the powder tight against the primer for more consistent ignition and usually higher velocities.

In the article just before this, I documented the difference in velocities from just pointing the gun skyward or toward the ground before shooting, to put the powder either against the primer (for the most part) or against the bullet, leaving a space. Clearly, you get higher velocities when the powder is against the primer, and if you don’t do either, and just let the powder slosh around any ole way, your velocities will vary over a wider range. Without a doubt, using more bulky powders that nearly fill the case will help this problem.

However, I have never used fillers and only have what others have told me or what I have read to relate to. I have heard of using all kinds of fillers, such as corn meal over the top of the powder and the bullet seated tightly so as to keep the two from mixing around in the case. I have heard of using Dupont Fiberfil, such as used in pillows, for a filler, but one shooter told me it left a residue inside the barrel that he didn’t like. I have also heard of a shooter cutting thin cardboard wads, like in a shotshell, to put over the powder in a straight case like the .45 Colt, and put the filler over that to prevent mixing of the two if they are jostled around a lot. That certainly seems like a good, but quite tedious method of keep the powder in the same place all the time, and at the desired rear of the case. Wads would not be practical in bottle neck cases like the 30-06 and similar rifle cases.


 

In early 2011, I got an email from another reloader who says he uses filler like this:

Another method of using a filler for light powder charges in large cases. I use the floss that is intended for charcoal aquarium filters. The one currently in use is the Hartz Fibre Floss. I bought it years ago when I was into raising tropical fish. I use it in loading pistol cases, most notebly the 41 mag loaded down to midrange velocities using medium burning powders such as A-5 and HS-6 behind lead bullets. I pull off a wisp that looks the right size and stuff it down over the powder before seating the bullet. I use the eraser end of a pencil to do this. I don’t weigh it but did for the sake of this explanation. What I use in the 41 case weighs between one and two grains on a reloading scale. It doesn’t pack in tight between the powder and the bullet, it just provides a barrier to keep the powder against the primer. A two ounce bag of this fibre will do hundreds of rounds and is inexpensive. I have compared loads with and without the fill and the ones with the fill always produce tighter groups at 25 yds. Hope someone finds this helpfull.


 

Now, here is another contributor on the topic of case fillers and he sent me a series of photos of how he does it, so I have chosen to publish his photos on this page. He uses toilet paper. I personally think that would be a good filler because it won’t mix with the gunpowder like some others might, is quite combustible and would leave very little residue in the barrel.

Here’s Frank Palamone’s story below.

Mr. Smith, I read your article on speed vs. powder position. Your observation is correct about powder position for consistent velocity. I’ve been using a 1.5″ x 1.5″ single sheet of toilet tissue pushed down over the powder with a wooden dowel. I use this tissue wad with my .43 Spanish, .45/70 trapdoor, .45 long colt, and also with my Mauser IG-71/84. I checked the performance through my Oehler M-35P 48″ rail. I take one single sheet of toilet tissue fold it two times and cut through the folds and get four squares of tissue for stuffing. Hope the pictures are helpful.

My load for the 43 Spanish is 24.5 grains of XMP-5744. This tissue wad works great. Tissue up the side wall is kept there by the seated bullet. I also gain about 100 fps muzzle velocity.

FOLD PAPER ONCE

First Fold

FOLD A SECOND TIME

Second Fold

CUT OFF ONE EDGE

Cut Off One Edge

CUT IN HALF

Cut in Half

YOU HAVE 4 SQUARES OF TISSUE

4 Square of Tissue

USE A WOOD DOWEL TO SEAT

Wood dowel to seat

I got the idea from a friend of mine. He lives in Grayson, Saskatchewan, Canada. He should be mention also, his name is Mick Boon. I’d like for Mick and some others to see it and review what you have to say about the Idea. I believe Mick used this filler when he lived in England. I think the rifle was the Mauser IG-71/84 11.15 X 60R called the .43 Mauser.

MD Smith

MD Smith

MD Smith has had a storied career from his family broadcasting AM radio business, to his 36 year career in TV broadcasting. He is a published fiction and non-fiction writer, earned his pilots license in 1965, and is the original founder of Reload Ammo in 1996. His loads have been successfully tested and used by others for more than 25 years.

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