Filler-reduce case capacity and increase pressure?

[lar45]

I saw somewhere someone mentioned this, but don't remember any of the details.
So if a filler is used to takeup extra case capacity, it would seem reasonable that you would have less effective case capacity. So would that increase pressure in the load?
What if you used 1/2" or more of felt, fiber... wad or COW?

I think this is different than useing a tuft of dacron to keep the powder in position.

thoughts?

[Buckshot]

..............Anything that increases the efficiency of smokless powder increases pressure, and this is what a bit of dacron, kapock, carded wool, or TP does. By keeping the powder against the primer more of it is involved at ignition.

The above I believe raise pressures more because of increased involvement of the powder at ignition.

Solid fillers such as the various cereal fillers, or felt and cardwads can cause increased pressures depending upon their use not only via increased powder involvement at ignition, but also through substantial case volumn restriction. Furthermore their possible not inconsequential weight adds to the load that has to be moved.

Wads, fillers and such really don't cause problems at low pressures unless used incorrectly. A cardwad against the base of a plainbased lead slug is of no consequence. Take the same cardwad and put it on top of the powder charge and you may have a problem.

................Buckshot

[Bass Ackward]

Sure pressure is raised. And just for the reason that Buckshot describes.

But that is not always a bad thing if you understand what is happening. The best way to do that is monitoring with a chronograph. And of coarse, smaller case designs show pressure the fastest. And the faster powders per a particular cartridge will also show first. Even where you are in the percentage of case fill will make a huge difference. And how much force you use to compress it adds in the equation.

I tried fillers in 44 Mag with 2400 just to experiment and recorded 20 fps more velocity than loads without when my charge was light enough that it was supposed to generate only 20,000 psi. Quickload estimated that velocity increase at less than 1/2 grain more powder. Cases sealed the chambers and you couldn't tell the gun had been fired after 50 shots. Accuracy with a PB bullet was improved dramatically and ES was 3 (no typo) for this load.

When the charge was raised to what should be about the 28,000 psi level, velocity was now increasing 60 fps over the load without filler to a velocity that Quickload predicted would take maximum pressure to achieve.

Once you cross .... that threshold with one means or another, pressures will then jump. So you can't really guess, you need to start way low and monitor as you come up.

[45 2.1]

That was me, and in addition to the above, you need to be cautious about how much compression that filler gets. It can set up in a solid mass somewhere in time after you loaded it and cause pressure problems that it didn't when loaded. Another problem with fillers is the use of cereal filler or any other that can absorb moisture out of the powder. The powder can then change its burn rate into a faster mode and raise pressure a lot.

[44man]

The only place I would ever use a hard filler (Cereal.) is on top of Black powder in my cap and ball to reduce loads. In the BPCR, wads are used to eliminate air space between the powder and boolit if the powder charge is not high enough.
In smokeless, a tuft of Dacron, not compressed, is the safest and will increase pressure the least. Stuffing a hard plug of anything over the powder is like seating a boolit deeper and if there is airspace between the plug and boolit I would be afraid of SEE. I would keep fillers light and fluffy and reduce charges and work up carefully. The only reason for them is to keep the powder close to the flash hole. Some powders are position sensitive. I don't like a large case with a tiny charge of fast powder. I wish they would make faster powders very bulky to fill the case more. SR4759 is one that is bulky for it's weight, one of the best for reduced charges.
Someone dumping 4 gr's of Bullseye in a 30-06 size case kind of scares me.

[Larry Gibson]

"Someone dumping 4 gr's of Bullseye in a 30-06 size case kind of scares me."

44man Guess I must scare the hell out of you 'cause I regularly "dump" 3.2 gr of Bullseye in '06 cases all the time, probably have done thousands of them. This is no flame as you're entitled to your opinions. Just want to state that I use this charge with the Lee TL314-90-SWC or Hornadys swaged bullet of the same persuasion and velocity is 925 fps. I also shoot a lot of RCBS 150s over 6.5 gr Bullseye which run right at 1100 fps. I use cases with the flash holes reamed. Accuarcy is excellent and they are very wonderful plinking/small game loads. Similar loads are used in most all of my rifle cartridges. I also "dump" lots of 6 and 8 gr charges of Bullseye in the 45-70 for use with 210HB and 275 gr cast bullets. Then there is the 4 gr of Bullseye I "dump" into the large .375 H&H case and load a puny 80 gr RB over it. No wad or filler is used what so ever. Never had a single problem with these loads.

Back to the subject of this thread; I gave up long ago using wads or fillers when using fast buring powders in small or large capacity cases. I've found with extesive chronagraphing, with the large assortment of powders available, that there is always a powder that gives excellent ignition and is not case sensitive under normal conditions. Mostly I've found Bullseye and Unique to fit the bill. On the slow end of the fast burning powders 4198, 2400, 4227 and 4759 work very well also. I use thes powders for medium range velocity loads (1200-1600 fps) with normal or heavy for cartridge cast bullets.

With normal or heavy weight bullets for the cartridge I prefer medium burning powders (I mostly use 4895 in cases from the .222 up through the .375 H&H and 45-70). It is with these medium burning powders that I use a dacron filler that is not compressed. I tried a lot of different fillers in years past, most of those mentioned. Dacron works becuase it raised the pressure so these medium powders burn efficiently at accurate cast bullet velocities. The dacron filler has caused none of the problems that some of the others do, especially in bottle necked cases. I have been using dacron as a filler exclusively for over 20 years.

Larry Gibson

[felix]

Larry, have you shot these 4 grainer loads straight down, or say up to 10 degrees upwards? ... felix

[Maven]

lar45, So would that increase pressure in the load? Yes it will and to a certain degree that's the point. Long ago the CBA published an article recommending the use of poly- or cereal fillers with slow powders, but only when the latter filled 75%-80% of the case. To cite one example, IMR 5010 wasn't designed with cast bullet shooters in mind (20mm cannon? .50cal BMG?), but small amounts of cereal or poly- filler with heavy CB's & mag. primers in bottle-necked rifle cases (7.5 Swiss & larger), tame its propensity for wide variations in velocity. Fired cases have little or no smudging on their necks too.

[lar45]

Thanks, that all makes alot of sence.

[Larry Gibson]

Larry, have you shot these 4 grainer loads straight down, or say up to 10 degrees upwards? ... felix

Felix, assuming you refer to the .375 H&H load. I have shot them at a pretty good angle down, 3-4 feet out in front of me testing for a hangfire or bullet stuck in the barrel. Neither happened with Bullseye and they went bang ok. I've also shot them at a 75-80 degree angle up shooting grouse sitting on limbs. BTW; horizontal is generally refered to as 0 degrees so 10 degrees up isn't much, assume you meant 80 degrees up(?). I've run numerous "muzzle up or down then raise or lower it slowly" tests across the chronograph with these loads. There was, of course, a larger extreme spread than when shooting normally but vertical stringing wasn't noticeable at 50 yards. It became apparent at 100 yards though. Since I very, very seldon shoot at those extreme angles I don't worry about it. The loads mentioned perfom quite well betwen -45 and +45 degree angles which is 99.99999999% of my shooting.

Larry Gibson

[felix]

In your terminology, Larry, I meant minus 80 degrees. That would be 4 feet in front of you. Thanks for the reply. ... felix

[3sixbits]

Just in case there might be a wildcatter out there reading this, I know of no better way to fire form brass than using the cream of wheat or kapok fillers and bullet lube plug with bullseye powder. Never lost a case, perfect ever time.

[44man]

What always scared me about Bullseye is there is almost nothing in a large case and even a double charge is almost impossible to see. I know the stuff works for a lot of applications but I do like to see my powder. I keep a can around for fire lapping and forming but just never liked it for light loads except in smaller cases. I never liked the idea of the powder being in all kinds of different spots in a large case. It's just a personal opinion.

[Larry Gibson]

44man

Actually I concur with your personal opinion and that is exactly what keeps me out of trouble with such loads. I developed the hard and fast rule that when I'm loading a case in a loadng block means it has powder in it. When loading such loads I do not put cases in loading blocks for any other reason. No double charges that way. Even if there was a double charge it would still not be a dangersous load with the light bullets used. These loads are on the bottom end of pressure for the cartridges. With these Bullseye squib/gallery/reduced loads I have intentionally worked up to over double charges (some were triple cahrge equivelent) with the only bad effect being no accuracy and some leading.

Larry Gibson

[44man]

Thats how I load too.
My friend was loading one shell at a time, got sidetracked and forgot to put the powder in one. That one had the bullet blown into the barrel by the primer and the next shot ruined his gun.
The loading block is a must!

[truckjohn]

As many folks here stated....

Using wads and fillers started with Black Powder shooting.....
which is a totally different animal than Smokeless for load density.

BP "Explodes" more than it burns. BP loads need to be 100% full, compressed
to keep the powder burning a little at a time rather than all at once.
Any air gap means a possibility the gun will go KABOOM -- when all
the powder burns at once .... so you use fillers, card wads, felt disks,
grease cookies, etc to soak up extra volume in the case -- to end up
with the powder charge and velocity you want.

Smokeless is very different.... as people have listed above.

Best regards

John

[drawerdoc]

Good Afternoon,,, What is Dacron filler and whare can i get it,,, Thanks

[Larry Gibson]

Good Afternoon,,, What is Dacron filler and whare can i get it,,, Thanks

Dacron is a "batting" material and is found in sewing/cloth shops. It is also available in many department stores as a pillow stuffing (comes in plastic bags). I prefer to get mine at the sewing shops in sheets. I buy several yards for only a few bucks. I then use very sharp scissors to cut it into strips and then cut the strips into squares. I eyeball it and cut the squares so they weigh about 1/2 gr. The size of the square depends on the thickness of the dacron sheets you get. In smaller capacity cases one square is sufficient as the filler but in larger cases I use two squares. I push the squares in the case mouth with a section of .22 cleaning rod. I store the cut squares in a coffee can with plastic lid. You can cut a lot of squares during a John Wayne flick. If you get the bulk dacron it's easy to pull a tuftoff that is close to 1/2 gr, just takes a little practice is all. I've run chronograph tests and cant tell the difference between a 1/2 gr tuft and a 1 gr tuft. The requirement is when the bullet is seated it pushes the dacron down to fill all the space between the bottom of the bullet and the powder.

Again let me say I use the filler with medium burning powders (for the cartridge) that fill up more than 1/2 the case capacity. I no longer use dacron as a wad with the fast burning powders.

Larry Gibson

[curator]

I'd be interested in a serious scientific look into Plastic shot buffer as a filler. How much does it reduce case volume, increase pressure? I have used it quite successfully in bottleneck cases where Cream of Wheat might have caused high pressures. I don't care for the smell, but it sure seems to give cleaner burning, more, and consistant velocities, and eliminate leading in rifle cartridges. Veral Smith feels that it coats the bore lubricating successive shots, reducing pressures further. All I can say is it works, particularly where one is using slow burning powders and cast boolits.

[drawerdoc]

Thanks i will try them both,,, Lloyd

[lar45]

Good Afternoon,,, What is Dacron filler and whare can i get it,,, Thanks
Try any sewing shop or an old pillow. I found a K-pok filled life vest at the thrift store for $1. I haven't had a chance to try it yet.

I use 5 gns of Dacron on top of RL-15 in my 470 NE loads. I haven't tried it without the Dacron, but hear that it can cause hangfires. Federal uses their 216 primer that is hotter than the 215 and RL-15 in their 470 ammo. they don't offer it for sale though.

On the case with no powder- This is a good argument for progressive reloaders. Each case gets one stop at each station, primer, powder, bullet seat and crimp. then you don't have to keep track of where you're at in the loading block.

[longbow]

On the subject of cereal fillers, I have used both cornmeal and cream of wheat for relatively light charges in .303 with cast boolits. So far it seems to improve accuracy and shows no excess pressure signs for my loads. Still working on them.

I have used both Unique and IMR 4320 with no problems.

I read an article by David Southall on http://www.303british.com/ regarding cast boolit loads and fillers. He recommends both cereal fillers and shotgun buffer for certain conditions and guns.

However, you can't just dump a bunch of filler on top of a load and hope for the best. Obviously due to the extra mass of filler and reduced case volume the pressure will be affected.

Like any other loading exercise you have to start light and work up.

There can be several benefits to using a granular filler:
- keeps small powder charges against the primer (assuming a slightly compressed load so no mixing)
- protects the boolit base
- seals the bore
- apparently scrubs the bore, and I read can completely remove leading though I haven't had the opportunity to verify that
- maybe most importantly if you double charge without filler you may not see it but with filler the cartridge will overflow indicating too much powder.

I have read comments about the "plug" of filler being squeezed through the shoulder and neck of the cartridge as a problem and while this certainly occurs, what about very slow burning powders? They don't all burn in the cartridge, in fact the goal is to have a long slow steady burn and pressure curve. Consequently I would suspect that a "plug" of powder is squeezed by the shoulder and neck and into the barrel.

In any case, there are lots of opinions pro and con but I will keep on working with the fillers as a part of working up certain loads unless I see some problems starting.

Longbow