school me on fillers: do they raise pressures?

[Whiterabbit]

I also want to know general info on fillers. Here's my specific case:

I shoot 338 lapua magnum in a Savage LRH111. It is by far my most accurate rifle. But it is TERRIBLY inconsistent! When the gun is shooting good, I can make an oval hole at 100 yards. Within minutes, hours, or days, I can have POI shifts or an expanded group. then just as inexplicably, I'm cloverleafing or get the amazing (for me) one round-ish hole again.

The barrel is NOT free floated, it contacts at the very tip of the stock. That will be corrected when I have a chance. The barrel gets too hot, too fast. I can shoot a couple rounds, then I have to give the barrel rest time. Sometimes my cloverleaf groups come when shooting 15-30 minutes between shots. Sometimes one after the other.

So there are clearly gun issues to be solved. BUT I think the load may play a role too and want to play with that too. This is what I'm interested in learning in this thread. Here are the LOAD details:

I'm shooting a solid copper 200 grain Nosler E-tip (wrong bullet for the application, I know). I'm using H4350 (wrong powder for the application, I know). With this combo, when the rifle is "on", it's REALLY on! But I have 83 grains of powder in a case that can take about 115. So there's a bit of open space in there! I have a suspicion this is affecting down range performance. Thing is, 84 grains is really a max load here. So if filler will increase the pressure, I don't want to jump in head first and just try-and-see.

So I'm interested in recommended fillers, recommended practices for loading using fillers (100% load density? over 100% required?, recommended storage practices (bullet tip up? down? rolling around an ammo can? does it matter?), and anything you guys think I should know before loading my next batch of brass.

Thanks guys!

[tomme boy]

if you are at max already, don't even try it. Get a different powder if you want to get 100% fill.

[singleshot]

+1 on tomme boy's response.

On the other hand, I've used greatly reduced charges with COW and coffee grounds as filler to produce a compressed charge where a full charge of the stuff was far less than 100% load density. The process works like this:

The filler weight plus the boolit weight is the ejecta and should ALL be treated as boolit weight. Now, scour the reloading manuals and find a smaller cartridge with the same bore size until you find a compressed load with that powder. Start with the "starting load" for that case using the ejecta weight (total of boolit and filler) and fill the rest with filler. You can work up close to the "max load" of powder, decreasing the amount of filler until you find the optimum accuracy. Generally, you want the filler to come just above the base of the boolit, i.e. no air gap.
If you follow this procedure, a few words of caution:
First, you can never allow the "filler" to absorb moisture, or it will not flow and will become a plug for your newly manufactured pipe bomb. I like coffee grounds better than COW for this reason. If you load and shoot in the same day, you add a margin of safety (provided you don't drop your loaded rounds in a puddle.)
Second, pressure will always be slightly higher than you'd expect because the filler flows out of a bottlenecked case slower than propellant gasses alone would.
Third, for the reason above, plus the decrease in powder charge, you WILL NOT end up with the same velocity, it will ALWAYS be lower, so don't even try to duplicate your velocity without filler using this procedure.

In the end, for instance, you can load your 30-06, to duplicate a 30-30 with a compressed powder charge that is more consistent than the powder would otherwise be in the "too big" case.

Also, don't use this procedure with powders faster than 4895. Really!

Ok, I think that about covers it.

Level III body armor donned, no AP rounds please.

[singleshot]

So, in the OP's application, I'd try to find a compressed load in 338 Win Mag and H4350, if one exists, and work from there. Consulting the Book of Armaments:
Lee Reloading 2nd edition says: 210 grain bullet, 70 grains compressed for a max load in 338 Win Mag, 63 grains starting. So, if it were me, I'd load 63 grains of H4350, fill the rest with coffee grounds, top it with a 200 grainer and record results, working slowly up to find best accuracy with above noted procedure.

But, that's just me, and I'd be using a paper-patched boolit, YMMV.

[singleshot]

But, the short answer to your original question is: YES! Fillers raise pressures. Dramatically.

[375RUGER]

I think I'd try slower powder first. Retumbo or something inbetween that and 4350. If you go to heavier bullets US869, WC872 should perform well and fill the case nicely. This is what you are wanting to accomplish anyway, fill the case and keep the same pressure.

[longbow]

Now that is a pretty good explanation for granular filler use singleshot! That is about how I do it. Now, I can't comment on fillers for .338 Lapua because I have only used them in .303 British.

I was having accuracy issues and read Davids Southall's article on filler on .303british.com then managed to get holds of him for some e-mailing and advice.

I found accuracy improved dramatically after I started using COW under cast boolits. I have never used it for "J" bullets or solids so cannot comment there.

Yes, as stated above, pressures will increase not only from the extra "ejecta" weight but probably even more due to both reduced cartridge volume and extrusion through the neck. You have to work up loads with filler included.

There are other options for filler as well:

- Puff-Lon (never tried Puff-Lon but it looks interesting: http://pufflon.com/newfront.html ) ~ note that Puff-Lon recommendation is to reduce powder charge 10% below max. recommendation
- corn meal (I find COW works better)
- COW with graphite added
- shotgun buffer
- polyester "puffs" like Larry Gibson and others recommend ~ this may be a good place to start as I doubt the pressure increases as much as with granular filler
- coffee grounds
- drier lint
- wheat bran
- wool... and I am sure there are lots of others

Some good reading on fillers if you haven't seen it:

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

I have used COW filler with fast powders under PB boolits with no problems after working up loads.

I will argue the moisture absorbing issue though. I loaded up several rounds with COW filler and put some outside in an open but protected baggie from October until mid summer through rain and snow and high humidity spring weather then pulled boolits from a couple of those rounds and some kept dry inside and there was no difference in the COW. It was somewhat packed in both cases but no obvious difference in those exposed to outside conditions. They shot exactly the same after being loaded for almost a year with no signs of excess pressure.

Where I might worry a little about using a granular filler is in a cartridge like .243 or .264 Winchester with large volume cartridge, small bore and steep sharp shoulders.

If you want to try filler, drop your charge considerably then work up with filler included. Also, do some searching and reading on use of fillers. Some like 'em and some don't... I do.

Longbow

[singleshot]

Longbow,

Thanks for the input. I have no experience with moisture affecting COW, just heard horror stories, could just be hearsay. Then again, I live in New Mexico so excess moisture isn't an issue being the high desert and all.

I also agree with the steep-shoulder theory, though I have no definitive testing along those lines. I did verify that the 338 Win Mag and 338 Lapua have similar shoulder profiles. I'm not sure how I'd deal with AI cartridges, since I've never owned one. But, I think Weatherby cartridges would be better with granular fillers (don't own one of those either.)

I'm interested in your use of COW with fast powders. I've used it with shotshells and straight-walled cases successfully...
Have you used COW and fast powders in bottle-necked cases?

[longbow]

Yes, but not bottleneck cartridges with big shoulders, just .303 British. I have had none of the "moisture" related issues or any signs of increased pressure after leaving loads for a long time due to "caking up" or any COW left behind the shoulder... though that may happen with a more pronounced and steeper shoulder.

I have not used shotgun buffer but many have and it is most likely a better choice than COW especially in bottleneck cartridges with steep shoulders. Here is an article on buffer in .308 Winchester by Mark Trope:

http://www.surplusrifle.com/shooting/castfiller/index.asp

Since I like to shoot PB boolits but was using GC load data for Unique, I was getting some leading so I decided I would download and add COW then work up and again, had no troubles at all with pressures and the loads shot well with no leading. Unique is the fasted powder I have used with filler.

Generally I use IMR4227 under filler in the .303. Both work well. These are not high velocity loads but are certainly not real light. I run from 18 to 22 grs. of IMR4227 under an NOE 316299 (202 grs.) or more recently my home made smooth boolits.

I made a Ness Safety bullet "clone" which weighs about 150 grs. and am finding that the articles seem to be right one even for my home made boolit. When tested, 17 grs. of IMR4227 gave best results for accuracy. I started at 22 grs. and have been working down. At 18 grs. I got some of my best groups. Not bench rest quality by any means but not bad from a Lee Enfield No. 5.

I tried IMR4064 with filler but did not get very good results. I did not work with it much though. My intent was a light load of slower powder but with 100% load density.

On the subject of no leading, in the LASC filler article the comment was made that an unlubed boolits tended to shoot better than lubed boolits and did not lead. I tried that and did get significant leading. Not sure of the reason but lubed boolits shoot well for me over COW and no leading. I tumble lube before loading.

Longbow

[Whiterabbit]

I would use slower powder, but load data suggests that super slow powders are not recommended for such a light bullet. If the recommendation is to use a heavier bullet, I'm just gonna sell the barrel. This shoots really well! .... just inconsistent.

I will likely back down the charge and try coffee grounds or dryer lint, those are PLENTIFUL around here. How much compression do I need to be confident I wont have much mixing if the rounds sit for a few months before firing? 1/4" after the bullet contacts the coffee or lint? less? more? I assume I need more "compression" if I use lint? just fill it to the top of the neck and seat? lint could compress. a lot.

[btroj]

I wouldn't be using a filler of any sort with a max load. Ever.

Use a slightly slower powder. Fix the bedding. Anything. NO filler of any kind.

[singleshot]

I would use slower powder, but load data suggests that super slow powders are not recommended for such a light bullet. If the recommendation is to use a heavier bullet, I'm just gonna sell the barrel. This shoots really well! .... just inconsistent.

I will likely back down the charge and try coffee grounds or dryer lint, those are PLENTIFUL around here. How much compression do I need to be confident I wont have much mixing if the rounds sit for a few months before firing? 1/4" after the bullet contacts the coffee or lint? less? more? I assume I need more "compression" if I use lint? just fill it to the top of the neck and seat? lint could compress. a lot.

If you go with used coffee grounds (dried in an oven) go back and read post #3 and #4 carefully. If you use drier lint, I have exactly zero experience. Your charting new territory in my book. Nothing wrong with that, BTW, I'd like to know if dryer lint works. :-)

[andremajic]

Something no one has suggested so far, so I'm just going to put this out there....If your cheek weld isn't consistent, and your head is in a different spot each time you pull the trigger, you can get extremely inconsistent, but tight groups. I have a sub moa rifle, but if I don't do my part, the groups open up to so-so accuracy.

Try chambering rounds and firing them one after another without moving your face from the stock at all. Do a string of about 5-10. Let me know if that helped. Use a sandbag or steady rest to prevent the rifle from moving as much as possible. Have a buddy help you chamber the rounds while your face is welded to the rifle the entire time.

Let me know if this helps.

Andy.

[dromia]

Have you looked at the sticky at the top of the page?

[Whiterabbit]

I'll look into it. But in my experience, the "standard" information usually does not apply to special circumstances, such as shooting an overbore high pressure magnum. As opposed to, say, making a reduced 45/70 load using a punched wad or lube "cookie" where no bottleneck and low pressures changes what can and is typically done.

[Whiterabbit]

Something no one has suggested so far, so I'm just going to put this out there....If your cheek weld isn't consistent, and your head is in a different spot each time you pull the trigger, you can get extremely inconsistent, but tight groups. I have a sub moa rifle, but if I don't do my part, the groups open up to so-so accuracy.

Try chambering rounds and firing them one after another without moving your face from the stock at all. Do a string of about 5-10. Let me know if that helped. Use a sandbag or steady rest to prevent the rifle from moving as much as possible. Have a buddy help you chamber the rounds while your face is welded to the rifle the entire time.

Let me know if this helps.

Andy.

Will do. If nothing else, it can not hurt to look into.

[dromia]

I think you will find Larry Gibson's and other contribution in that thread quiet illuminating, Larry has written a lot on here about wads and fillers, stickies are stickied with good reason.

[Nrut]

WR,
You are using the wrong bullet and the wrong powder by your own admission and you want people who don't own such a cartridge to give you advice on what you are doing wrong?!?!

[Whiterabbit]

well, I want to head off that direction of conversation by admitting that upfront then stating that "despite that" the potential for excellent performance is there.

There's enough minutia that needs to be written into language of an internet forum topic to ensure the thread goes in the direction the OP wants that someone could write a book.

[longbow]

While the use of granular or at least non "puff" fillers is pretty controversial, one point I will make is that if there were truly a danger from using a case filling semi solid (even COW does compress) filler then I doubt that surplusrifle.com would be posting "how to's" or Puff-Lon would be selling a product that could lead to property damage or injury due to use of their product. In this litigatious society we live in, their lawyers simply wouldn't let them.

Loads worked up to safe pressures with fillers should pose no more danger than working up any load. Sure, you can't take a max load and simply dump some filler in to top off the case. That would be about as dumb as putting in more powder to top off the case.

We have a lengthy thread on loading 6.5 Swede with shotgun buffer between powder and boolit that had quite a following. I don't recall too many naysayers on that thread and if memory serves, no guns were blown up or even damaged.

My opinion anyway.

Longbow

[nanuk]

I think I remember reading somewhere that displacing powder with COW volume to volume kept pressures relatively stable

in other words, if you have XXK pressure with Y.Ycc of powder, then loading with Y.Ycc MINUS Z.Zcc of powder and adding Z.Zcc of COW produced the Same pressure.

it would be a way to save powder, but could be potentially dangerous if playing at the top end of pressures.

IIRC, the experiment did not go low enough to find where pressures dropped or spiked....

I don't think there is a lot of experience in this area, so play careful

this is an area that could use more experimentation, but would require a pressure testing setup.... and for that, I'd have to sell all my guns to be able to buy one! Then what......

[45 2.1]

I think I remember reading somewhere that displacing powder with COW volume to volume kept pressures relatively stable

in other words, if you have XXK pressure with Y.Ycc of powder, then loading with Y.Ycc MINUS Z.Zcc of powder and adding Z.Zcc of COW produced the Same pressure.

it would be a way to save powder, but could be potentially dangerous if playing at the top end of pressures.

IIRC, the experiment did not go low enough to find where pressures dropped or spiked....

I don't think there is a lot of experience in this area, so play careful

this is an area that could use more experimentation, but would require a pressure testing setup.... and for that, I'd have to sell all my guns to be able to buy one! Then what......




You folks need to realize that different fillers raise pressure differently... because they either flow or bridge differently in different case shapes and combustion area sizes. There are a few people who do know most of this, but not many things are a given rule involving fillers/buffers. It entirely depends on what you are trying to do with the components you are using at the time.

[1Shirt]

Seldom load a max load of anything and if it is a max load, it would be with jacketed blts. . My rule of thumb from years of experience with fillers with cast is:

If the powder charge with powders faster than 2400, NO Filler! With 2400 and most of my 30 cals, I use Dacron fillers (no compression-just enough to keep the powder to primer). With slower burning powders in rifles, if the charge is less than 2/3 of the case below the neck I use a filler.

Not a recommendation, just what works for me. I weigh all of my finished cast rifle loads for consistency and expect finished weights to be within 3/10 of a grain. Using fillers, and weighing finished cases is time consuming and an extra process, but I try never to fix what works for me and isn't broken.
1Shirt!

[Larry Gibson]

I do not recommend any filler or wad with a jacketed bullet.

All fillers wil raise the pressure with a given load. How much depends on which filler is used as 45 2.1 mentions.

Jacketed bullets require a lot more psi to engrave into the rifling than do cast bullets. Not only are pressures raised but the stage is thus set for chamber or barrel ringing. Again; I do not reommend any filler or wad be used with any jacketed bullet.

Larry Gibson

[buckwheatpaul]

Filler does increase pressure...the best information I have found on it is "Jacketed Performance With Cast Bullets" by Veral Smith. He is a mold maker and has done extensive testing on cast bullets....hope this helps....Paul

[Char-Gar]

If fillers didn't have an effect on how the pressures is realized, then nobody would use them.

[1Shirt]

Could not agree more with Larry on never using fillers of any kind with Jacketed!
1Shirt!