I have heard some of the 'Old Timers' talk about duplex loads and useing Dacron to seperate the powders. I know that with today's powder selection this is not needed. My question is has or can you use the Dacron to fill up the empty case volume in lighter charged loads?

Dacron is an excellent filler if used correctly. I use it with cast bullets only. I never heard "old timers" talking about "seperating powders" in duplex loads. I have heard them mention using the fillers to keep the powders slightly compressed together so they would not mix though.

Here is what and how I use dacron as a filler;

I have for many, many years found dacron (polyester fill) to be the best "filler".

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

I almost always use the dacron filler in rifle cases with the slower “fast” burning powders (4227, 4759, 5744, 4198, etc.), the medium burning powders (RL7, 3031, 4895, etc.) up through the slow burning powders (RL19, AA4350, H4831SC, RL22, 3100, etc.) that give around 80% or less loading density. The dacron filler is used only 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. The 6 to 10" section gives plenty to hold onto and sufficient "feel". Merely hold the chunk of dacron over the case mouth and shove it in with the rod. Sometimes it takes a couple three pokes to ensure all is inside the case mouth. I poke the chunks in until the are at the botom of the neck or at least all in the case. It doesn’t matter. What you want is to let the base of the bullet finish pushing it down and adding any compression. Thus I do not push it down on the powder but let the bullet do that when the bullet is seated. Using the right size chunk of dacron this method then provides a "filler" in the air space between the powder and base of the bullet.

A small length of coat hanger works for the .22-7mm cartridges and an unsharpened pencil works well for .45 cals.

Larry Gibson

quote:

Originally posted by LongShot007:
I have heard some of the 'Old Timers' talk about duplex loads and useing Dacron to seperate the powders.

No, it is to fill the space between the Bullet and the Powder, not between Powders.

quote:

I know that with today's powder selection this is not needed. My question is has or can you use the Dacron to fill up the empty case volume in lighter charged loads?

It was responsible for a lot of articles in the NRA magazine during the `50s. They were able to document a bunch of Chambers and Barrels with "Rings" in them created by the Fillers. That is as close to a barrel rupture as you can come without it happening. So, it is not a good idea to mess with them.

Fillers are not needed with the Special Powders available in the USA.

"It was responsible for a lot of articles in the NRA magazine during the `50s. They were able to document a bunch of Chambers and Barrels with "Rings" in them created by the Fillers. That is as close to a barrel rupture as you can come without it happening. So, it is not a good idea to mess with them."

Not quite correct HC, that was with "wads" not fillers, especially not with dacron fillers.

Larry Gibson

And larry is WRONG again, or as usual.

It is common practice, when loading RL-15 or Norma 203B in large old Nitro Express cases, to use Dacron filler or foam wads to hold the pwoder against the primer.

When using a powder such as 5744, the manufacturer says do not use any filler with this powder. Whenever I can I try not to use a filler.

Dacron filling was intended for one purpose only in regards to reloading , as Rusty stated keeping reduced powder charges AGAINST the Primer. This prevents primer flash over ,A DANGEROUS condition which spikes pressure detonation ; Similar to a grenade .
Duplex loads are NEVER SEPARATED BY DACRON !!!.

It's normally used with reduced charges of faster powders in larger volume cases ,which normally require slow powders or bulk type cowboy shooting powder ,testing and in some instances fire forming cases .

I use it in old Military obsolete cartridges so I can shoot the dam things ,as ammo is OLD dangerous and EXPENSIVE to purchase if newly manufactured .

There is a fair amount of information out there that dacron can and does/did cause ringing of chambers. It can, on occasion, form sort of a gooey blob that affixes itself to the base of the bullet, effectively momentarily plugging the mouth of the case. In short, there are reasons why kapok was the recommended filler, and later cotton as well. Neither is susceptible to melting, as dacron is. It takes a bit to make either of them burn, so they are blown out of the barrel, if I understand correctly.

This is a very controversial subject with as many different views as there are shooters, and everyone is free to do what they believe is best. I use dacron in a few different calibers in nitro for black loads. In the past year I've shot one pound of dacron ten grains at a time out of my 500-450 BPE. I can tell you, that in my experience, there is no sign of melting. I've picked up all that I could find, which has been most of that pound, to put it in the garbage. I do not believe there is enough time for the heat to transfer to the dacron to cause it to melt. If the heat would melt dacron it would set dry cotton or kapoc alight. Without the dacron I can't get reliable ignition in some calibers much less consistent ignition, so I'll continue to use dacron.

Hot Core. Specifically which issure of the AR are these articles in? I have very copy of the AR in the 50's. Frankly, I think you're wrong. I've been shooting cast bullets with fillers for over 50 years sometimes using fillers and sometimes not. The only fillers I object to are cereal fillers like corn meal or Cream of Wheat. In fact, COW compacts into an almost solid mass that would/could seriously raise pressures in a bottle neck cartridge. Just ask me how I know about that one. I've used kapok, dacron and even wadded toilet paper for a filler, With the TP, it was very light loads of Unique and I use a 1/4 square of TP lightly tamped against the powder to keep it in place. I've never had a problem with the fillers mention, even the cereal type but that was in the straight cased 45-70. I never used them in bottlenecked brass.
Paul B.

quote:

Originally posted by Doubless:
... if I understand correctly.

You do!

Paul, I don't know. It has been 50-60yrs since I read about it. I'm glad you have never had a problem with them and hope you don't. I feel sure it was the NRA magazine, but that could be wrong. Been way too long.

Your reasoning is what fueled the debates back then - some never experiencing a problem. I just choose to avoid "potential" problems when I can. With the High Bulk Powders available today, I just don't see a need for Fillers at all.

quote:

My question is has or can you use the Dacron to fill up the empty case volume in lighter charged loads?

Not with 100% safety. Using kapok in 30-30 & 30-06 with fast burning light charges didnt make my loads more accurate. Switching to IMR 4895 did with cast bullets.

quote:

It has been 50-60yrs since I read about it. I'm glad you have never had a problem with them and hope you don't. I feel sure it was the NRA magazine, but that could be wrong. Been way too long.

Hot Core

You're just killin' us here....you say that after you emphatically say I was wrong?

I do believe you are right about one thing though...it has indeed been "way to long"for you as your memory has indeed failed you.

Larry Gibson

My memory (faultless) was that it was the
black powder boys who had problems. They used
straight cases.
If you want more info check with them.
Good luck!

Hey Paul, If you scan through some of the old issues, check the "Letters from Readers" section, or whatever it was called back then. Some of the HEAVY Weights of that Era would write admonishments of some of the writers(who knew as little about the subject as larry).

I believe Col. Whelen may have been one of the guys in the running debate.

Keep tap dancing Hot core....try learning the difference between "wad" and "filler' when the bands not playing.....

Larry Gibson

The article concerning the ringing of chambers was concerning black powder rifle and the use of cotton as a filler. I posted a synopsis of the article several years ago on the forum. I've tried searching for it, but can't find it.

Boy, am I ever confused now. Rather than general comments on the use of fillers between powder and base of bullet in "lighter" cast bullet loads, I will appreciate comments on the following:
.404 Jeffery
.429" hard-cast GC boolits drawn down to .423" in two steps.
Boolit weight 325gr.
Looking for velocity 1900-2000fps.
Recommended powder and charge? Is use of filler recommended or optional?
Many thanks......

Here are some testimonials on the subject which I feel is quality reading on the subject .

http://www.lasc.us/Brennan_6-5_WadsFillers.htm

I will only add ; I personally use the tuffed variety an not sheet pressed Dacron . I also use ONLY enough to cover powder charge so it doesn't slip away from the primer . I've never experienced ANY problems , provided Powder was fast enough and the charge low enough.
In nearly 30 years of reloading using that method . In 44 years of reloading I've had near as I can remember #5 misfires and ALL of them were from CCi primers . Extremely lucky or extremely careful ? . I believe it's BOTH .

I have seen fellow shooters ( in person )use wads and suffer serious damage too their weapons . Powder type an charge wrong or wads to blame . I don't know with degree of certainty .

I do know in regards too a Model 21 with regular reloading ,a punk load failed to clear the wad an the operator was unaware it happened .
Next round down BULGED the barrel !!!. Use common sense extreme caution an work up SLOWLY CHECK BORE and CASES for signs of problems PRIOR TO THEM HAPPENING .

quote:

Originally posted by Rusty:
The article concerning the ringing of chambers was concerning black powder rifle and the use of cotton as a filler. I posted a synopsis of the article several years ago on the forum. I've tried searching for it, but can't find it.

Hey Rusty, That would be a totally separate thing and article from what I'm talking about. The Debate went on for a long time.

Mike,
You might try 44-45 grains of 5744, NO FILLER.
QuickLoad says that's a low pressure load and around 2000 FPS out of a 26 inch barrel.

I use that 46 of 5744 with some 300 grain Hawks. I get around 2120 out of a 26 inch barrel.