poly fill

[jcw1970]

Newbie question here. Is there some formula on how much poly fill you use?

[Larry Gibson]

This may provide some guidence. I have use dacron (assuming that's what you mean by "poly fill", polyester)

Larry Gibson

I don't use the dacron filler or a wad either with the fast to medium burning "fast" pistol /shotgun type powders. I find a fast burning powder that is fast enough to ignite and burn efficiently at the velocity I want.

For use in rifle cases with slow “fast” burning powders (4227, 4759, 5744, 4198, etc.) up through the slow burning powders that give around 80% or less loading density I use a dacron filler between the powder and base of the bullet. The “dacron” is polyester fill as commonly found in pillows and toys. It also comes in sheets called “batting” . It can be obtained very reasonably at most any fabric store.

The dacron batting comes in various thicknesses. I prefer that which is about 5/8" thick. My wife recently bought me 10 yards which will give many, many thousands of cast bullet loads. With this current batch of batting I cut it initially across the width into strips about 3/4" wide. I then "eyeball" cut 1/2" wide chunks which is close to 3/4 gr.

A smaller chunk is cut for 1/2 gr and larger for a larger amount. I've cut some chunks that weight 1/2, 3/4, 1, 1 1/4 and 1 1/2 grs and have them in a "snack" baggie stuck on a poster board above my loading bench for quick reference when I need to cut new chunks. The batting will run thin and thick throughout the sheet so I again just "eyeball it" based on the thickness of the batting when cutting the chunks.

Pretty extensive tests have demonstrated that the weight of the filler does not have to be exact, only close. What is important is that there is enough so that it “fills" the space between powder and bullet. A little too much hurts nothing but too little poses problems. That's why I have the different size "chunks" so I can use the right size for the case capacity I am filling. For example; with most medium burning powders (3031, 4895, 4064) in and '06 to function an M1 a 3/4 gr dacron filler is about right. With slower powders that give a higher loading density like 4831 a 1/2 gr filler is about right.

I use a section of .22 cal cleaning rod in cartridges of .30 - .375 cal to push the Dacron chunk inside the case just so it is all in. Some chunks go all the way and some are up into the neck. It doesn’t matter. I do not push it down on the powder but let the bullet do that when the bullet is seated. A small length of coat hanger works for the .22-7mm cartridges and a pencil works well for .45 cals.

[fourarmed]

Just enough to loosely fill the space between the powder and the base of the boolit. If that space is very large, you are presumably using a fast-burning pistol powder which ignites easily, and needs no filler. If you want to try it anyway, most users recommend a half to one grain. I like quilt batting rather than the bulk pillow stuffing. I cut it with scissors, and it is easy to keep the volume uniform without weighing.

[StarMetal]

This may provide some guidence. I have use dacron (assuming that's what you mean by "poly fill", polyester)

Larry Gibson

I don't use the dacron filler or a wad either with the fast to medium burning "fast" pistol /shotgun type powders. I find a fast burning powder that is fast enough to ignite and burn efficiently at the velocity I want.

For use in rifle cases with slow “fast” burning powders (4227, 4759, 5744, 4198, etc.) up through the slow burning powders that give around 80% or less loading density I use a dacron filler between the powder and base of the bullet. The “dacron” is polyester fill as commonly found in pillows and toys. It also comes in sheets called “batting” . It can be obtained very reasonably at most any fabric store.

The dacron batting comes in various thicknesses. I prefer that which is about 5/8" thick. My wife recently bought me 10 yards which will give many, many thousands of cast bullet loads. With this current batch of batting I cut it initially across the width into strips about 3/4" wide. I then "eyeball" cut 1/2" wide chunks which is close to 3/4 gr.

A smaller chunk is cut for 1/2 gr and larger for a larger amount. I've cut some chunks that weight 1/2, 3/4, 1, 1 1/4 and 1 1/2 grs and have them in a "snack" baggie stuck on a poster board above my loading bench for quick reference when I need to cut new chunks. The batting will run thin and thick throughout the sheet so I again just "eyeball it" based on the thickness of the batting when cutting the chunks.

Pretty extensive tests have demonstrated that the weight of the filler does not have to be exact, only close. What is important is that there is enough so that it “fills" the space between powder and bullet. A little too much hurts nothing but too little poses problems. That's why I have the different size "chunks" so I can use the right size for the case capacity I am filling. For example; with most medium burning powders (3031, 4895, 4064) in and '06 to function an M1 a 3/4 gr dacron filler is about right. With slower powders that give a higher loading density like 4831 a 1/2 gr filler is about right.

I use a section of .22 cal cleaning rod in cartridges of .30 - .375 cal to push the Dacron chunk inside the case just so it is all in. Some chunks go all the way and some are up into the neck. It doesn’t matter. I do not push it down on the powder but let the bullet do that when the bullet is seated. A small length of coat hanger works for the .22-7mm cartridges and a pencil works well for .45 cals.


TEN YARDS! TEN YARDS! Geesh Larry, what are you shooting...a couple mini-guns? You better believe that will last thousands of rounds.

Joe:Fire:

[jcw1970]

thanks for the info.

[jonk]

I never found how some guys could use only 1/2 to 1 grain. I buy the loose stuff, not in sheets. But when I poke 1/2 grain in over a case say 1/2 of powder, it comes no where NEAR filling it. 3-4 grains does for me. YMMV.

[Larry Gibson]

TEN YARDS! TEN YARDS! Geesh Larry, what are you shooting...a couple mini-guns? You better believe that will last thousands of rounds.

Joe:Fire:


I guess we could say she got carried away but when your wife buys you something for shooting (of course it was on sale!) you can't complain no matter what:-) I am good on dacron for a while though......

Larry Gibson

[JW6108]

I never found how some guys could use only 1/2 to 1 grain. I buy the loose stuff, not in sheets. But when I poke 1/2 grain in over a case say 1/2 of powder, it comes no where NEAR filling it. 3-4 grains does for me. YMMV.

Same for me; that much will also act as sort of a fibrous gas check. I no longer use gas checks in light loads using this amount and type of filler.

[Tokarev]

Question: I tried some fiber fill wads in the antique revolver loads with Unique and it melted into nasty yellow gunk, which then solidified all over the cylinder face. Did I get wrong type? I tried both stuff from the fabric store and from the sofa pillows. Someone told me that there is low temp and hi temp variants and only the later is suitable as wad.

What am I doing wrong?

I will be loading some rounds in the near future where the bullet will have to be supported in the case prior to crimping and thought that fiber fill wad would be suitable for that role.

[Larry Gibson]

jonk, JW6108

Depends what powder you are using (note in my above post that I do not use a filler with fast burning powders or a wad with them either. With the correct selection of such a fast burning powder neither a wad nor a filler is necessary for consistant ignition.) . With an appropriate medium or slow burning powder than occupies 60 to 85% of the case capacity a 1/2 to 1 gr tuft of even loose dacron is sufficient as a filler in cases with a capacity from the 30-30 up through the '06. The filler does not have to be tamped down or be a solid mass. It only has to occupy the empty space and hold the powder back. !/2 to 1 gr, depending on the case capcity, does in fact do it.

Tokarev

Note I do not use a filler with Unique in any loads. At one time I did use it as a wad with Unique (before I learned it wasn't necessary if the right powder was used) in some cartridges with closed breeches. I never used it as a wad or filler in revolver cartridges. I never had such a "nasty yellow mess". I would guess you indeed did "get the wrong type".

Larry Gibson

[GrizzLeeBear]

I've been trying some loads with filler in 30-06. Loaded a 311466 150 gr. boolit with 33, 34 & 35 gr. of RE-15 and a 1/2" x 1/2" x 1 1/2" dacron filler (quilt batting). All shot well with the 35 gr. load being the best, right at 1" 5 shot group at 100 yds. I'm guessing the 35 gr. load fills the case about 70% full. This size piece of dacron fills the case from the top of the powder to the case mouth. I use a pencil to push it in so that the top is just below the mouth and sitting on the powder, then let the bullet push down on it when seating so that it fills the space between the powder and the base of the bullet. Doesn't really compress the filler, just enough to keep it snuggly in place. I weighed one of the dacron fillers and it weighs almost exactly 1 grain. I'm going to load some more at 35 gr. and 36 gr. and see how they do.

[kbstenberg]

Is a filler helpful in lower velocity pistol rounds. I was advised by a Sierra Tec. that unless the reload recipe calls for it don't use any. I am looking at Cal / 245 gr bullet / 6 or 7 gr. Clays. For practice field loads

[Tokarev]

So do I gather it right: Dacron/Poly Fil/Fiber Fil burns completely into ashes in rifles, but gunks the revolvers?

[jonk]

Not only doesn't it burn, it comes out puffy yet in my experience. But that is limited to bolt action rifles.

Regarding the amount, Larry-

Real life example here. 8mm Mauser. 28 gr of IMR 4895, 150gr bullet. 1/2 grain just disappeared down there. NOT tamped down, NOT compressed, just loose fluff pushed into the case with a small nail. 2.5 grains was the MINIMUM I could use to fill the case.

Again, your mileage may vary.

[JW6108]

Not only doesn't it burn, it comes out puffy yet in my experience. But that is limited to bolt action rifles.

Again, your mileage may vary.

Same here; it works for me.

[GrizzLeeBear]

Is a filler helpful in lower velocity pistol rounds. I was advised by a Sierra Tec. that unless the reload recipe calls for it don't use any. I am looking at Cal / 245 gr bullet / 6 or 7 gr. Clays. For practice field loads

No. There is no need to use fillers with fast pistol or shotgun powders, especially when loading in pistol rounds. They light real easy and are not very position sensitive.

[BruceB]

Based on MANY direct-comparison tests (hundreds!) with/without dacron fill with relatively-fast powders, there IS a benefit to using the dacron in some of my loads. Such powders as 2400 and 5744 have demonstrated lower extreme spreads and slightly-higher velocities for me when using the dacron, and also slightly-improved accuracy in some examples.

The question is whether or or not these improvements warrant the increased hassle of adding dacron to each case. Lately I find that I'm using the filler less with these quicker powders, because the results are good enough for my purposes without the fluff. I'm going to re-shoot a recent series of 2400-no-dacron /.303 British loads WITH dacron, just to see how a "new" rifle reacts. Usually, I shoot the comparison tests on the same range outing, but I was too eager to get this rifle shooting on this occasion.

I certainly do frequently use dacron with anything slower than 5744. My preference is for the loose tuft-style fill, not the sheets, but that's just a matter of choice and habit.

My "formula" for using the stuff is to make tufts which are plainly large enough to fill the empty space in the case WITHOUT UNDUE COMPRESSION. It does not take a dense mass of fiber to hold the powder in place. Try a few tests in a clear plastic tube of some sort, and you'll find that even a tuft that you can almost SEE through will hold the powder in place. I did this with a clear tube which I carried around in my pocket for a week or more, and even VERY "thin" tufts worked well. Do not use dense masses of dacron!

[JSnover]

So do I gather it right: Dacron/Poly Fil/Fiber Fil burns completely into ashes in rifles, but gunks the revolvers?

I tried it years ago in a 6" .357 with no ill effect. Looked like I shot a puff of feathers every time I pulled the trigger but there was no residue, nothing out of the ordinary to clean up.