Your experience with Dacron filler?

[jlow]

Thinking I want to try this. What I have notice, as most people have is the fuller the case, the more consistent the MV and better the precision (group size). I understand the rationale for this but one problem with this is with a good slow powder like Varget, usually you are getting close if not exceed the max load and you are getting pressure signs like ejector swipes. So I am thinking that perhaps backing off the load and using a filler to get more consistent ignition will do the same thing. Now I understand that putting in a filler will also increase pressure and you need to work up to it but my question to the experts here are:

1) With something like 308 using Varget, have you seen more consistent MVs/Accuracy with this method? I am using Lapua brass and 175 SMKs.

2) If one can get the same results i.e. more consistent MV and greater precision with lower powder load + filler does the pressure signs raising its ugly head because the filler has increase pressure despite the lower powder weight?

3) Using Dacron as a filler and enough to prevent powder movement, has anyone seen a problem in terms of the material not burning up completely and depositing on the chamber/rifling?

 

[Dan877]

No experience with Dacron, but in my light cast-bullet loads that only partly fill the case I usually use a small amount of single-ply toilet paper to hold the powder in place. It only takes a small round-ish piece, not much larger than the case body diameter. I did find it seemed to help accuracy slightly.

I tried using paper towel rather than tissue once, but it blew burning paper out the end of the barrel and almost started a grass fire, so I never did that again. Never had that problem with toilet paper.

 

[jlow]

Thanks Dan877.

Yes, I understand that a variety of fillers have been tried by folks in the past including toilet paper, COW, etc but it appears at least in my limited reading that Dacron seems to be the favorite although there appears to be some who thinks that it left a deposit in the chamber whereas others reports no problem after thousands of rounds… Looking for experience on this board.

Will try to not start any fires! ;D

 

[Powderfinger61]

I did a lot of target shooting years ago with .38 spl using 3 gr Bullseye and 148 gr wad cutters filled with Dacron, No crimp....consistent results with no issues of buildup in barrel. Burns clean.
Stay focused to avoid double charges with fast powders.

 

[jlow]

Thanks Powderfinger61, this will be for bottle neck rifle cases using a slow burning powder (Varget) and so not possible to double charge but I will still work up the load.

For pistol, I use Titegroup but that stuff seems to be super accurate as is even though it use so little space that you could triple charge the stuff… No plan to do any filling with the pistol.

 

[bigedp51]

I have used Dacron filler in 45-70 and .270 Win reduced loads, the Dacron was preferred over cornmeal or COW because it would not bunch up and become restricted in the shoulder neck area of a bottle neck case. In fact I was always under the impression that COW type substances should only be used in straight sided cases.

I never had any problem with Dacron residue or deposits, but with the lower pressure 45-70 reduced loads a short lived flaming mass of dacron could be seen going "poof" a short distance from the muzzle.

Even with powders like SR4759 or Trail Boss your starting at 70% of case capacity and no fillers are required.

 

[jlow]

Thanks bigedp51! Good to hear of your experience – that is comforting.

Yea, I brought up the other fillers because it is as you say used by the straight wall shooters and just want to get that out of the way and concentrate the discussion on Dacron since I am only interested in the bottle neck stuff.

Must confess my interest in fillers is completely focused on getting my loads to perform with lower SD and better precision. No real interest in reduced loads except to avoid getting pressure signs. So on that topic, when you used fillers in rifle cartridges, did you do any test that might show your load performing better in terms of SD and precision?

 

[bigedp51]

I do not and never had a chronograph so I can't give you the type data you are asking about. The Dacron filler stopped the cartridges from being position sensitive and vertical stringing with reduced loads. I later switched to SR4759 powder that had much better loading density and did not require Dacron fillers.

Did you ask anyone for Quickload loading data to help with what you are trying to do.

In Elmer Keith's book "Hell, I Was There" he experimented with threading a tube inside the flash hole of the case and lighting off the powder behind the bullet. According to Mr. Keith this was the correct end of the case to start the powder burning and his test results gave better accuracy. BUT it was a pain making the cases and not worth the small gain in accuracy.

 

[polebilly]

Jlow, I have been using Dacron filler in a 30 TC. The loads are mostly SR4759 and 5744 with cast bullets. I shoot a lot of cast to practice off hand due to my thriftiness ( ie cheap). The reason why had to do with unburned powder in the barrel after most shots. The filler has totally stopped this from happening. Understand these are rather low pressure loads. Your idea of reducing SD by using a filler in higher pressure loads is interesting. If I had the time or maybe when I find the time this would be a great experiment. Good luck with this and let us know if you come up with any results.

 

[jlow]

Bigedp52 – yea, I am planning to chrono some rounds with that Oehler I got setup last year, its been working well. Vertical stringing at 600 is what I am working to reduce and I figure I can monitor that with the chrony at the 100 since my access to the 600 is limited.

Don’t have Quickload but I am not sure what type of input it will take to help assess the use of fillers. Is it setup to do that type of analysis? Perhaps someone can comment?

Hopefully this will not be as painful as Elmer Keith’s method – LOL! My current bottle neck handloads are pretty labor intensive so adding the fillers will hardly make a dent in that process. One can look at that as either good or bad…

Polebilly – good to know that the fillers work for you in the 30 TC, yes my understanding is that the filler is also used with cast bullets but still it is good to hear that the Dacron filler is not causing you any problem.

 

[lpreddick]

jlow: DO NOT USE SHOT BUFFER IN A BOTTLE NECK CARTRIDGE!!! i asked myself the same question as you. had a load that was working but had a good bit of empty case and i also was aware that a nearly full case burned powder more efficently and the pressure curve is supposedly better, etc. read where the blackpowder STRAIGHT wall cartridge shooters used fillers when using smokeless powder and shot buffer was one of these fillers. in my 22 BRX i reduced the charge by 1.0 gr and added the shot buffer...NOT GOOD!!! a very loud BANG, powder residue in the face, bottom metal flew open and bolt was locked. stiller predator action and i finally got it open. flash hole was 3X normal, case shortened, and 2 mm of brass flowed into the empty ejector opening, extractor sheared off and piece was welded to case! replace extractor and gun is ok. the melt point of shot buffer is less than 400 degrees f and the stuff probably melted into a plug that was forced thru a .22 cal hole! the pressure was possibly 90,000 psi+! cow will also melt or cook into a hardened cake-like material, so i would be very hesitant to try it in my situation. i have used cow to ff ackley cases and 6br cases and will occ see a caked cow on the inside of the shoulder and it is VERY hard and has to be scraped out, so i now am using half the cow and fill with the shot buffer that is now not exposed to heat. ffing is the same and there is no caking of cow. some say cow is slightly abrasive and contains nacl(salt). don't have any experience with dacron and as you might have guessed, my case filler experimentation with loaded rounds is over. be careful everybody.

 

[jlow]

Lpreddick – Your advice is good but you are talking about using shot buffer and COW which is not recommended for bottle neck stuff for exactly the reason you mention which is they will form a plug and cause major pressure spike.

The filler I am asking about here is Dacron which is a fluffy synthetic material that has very little mass and burns up. The only concern I have about Dacron is a report I read where they mentioned the melted stuff depositing on the chamber surface.

 

[357Mag]

jlow -

Howdy !

I put "PUFFLON" atop a thin "wad" of tissue paper, to keep the filler from encroaching on the powder.

Has worked great for me, in multiple calibres; and in .35cal w/ both cast and "J"-word bullets.


With regards,
357Mag

 

[rvn1968]

When I was younger and dumber;hard to believe but true;An older shooter showed me the tissue trick.Being younger and therefore smarter,I used flash paper to be sure there would be no residue.Thank GOD Ruger made their Blackhawks so strong.Flash paper is pure gun cotton/nitro.

 

[jlow]

357Mag – thanks! That PUFFON is expensive but I might have to give it a try since it will last quite a while considering who much I will be using.

Rvn1968 – yikes! I guess a case of too much of a good thing!

 

[StevenDzupin]

I've tried the Dacron in .375 H&H with cast and jacketed for reduced loads to keep
the powder closer to the primer.

With boatail projectiles accuracy suffered greatly.

Switched to Federal 215 primers and no need for Dacron.

Never saw a flaming puffball just white shredded fiber puff. LOL

Regards,

Steve .... ....

 

[Bugs]

Take a look at the reply by lpreddick. . . . I darn near blew up a .257 weatherby using a product called pufflon as a filler. Worked fine in 45-70 loads with 2400 powder but it caused me a lot of grief in bottleneck cases, esp when loads were warm to start with.

 

[jlow]

Steven Dzupin – thanks for the input, at least it is safe which is good to know.

Bugs – you cannot just put in fillers if you have a warm load because its presence reduces case volume. We all know what a reduction in case volume will do to pressure. No one should consider doing this unless they are willing to work safely and work up the load again.

 

[bigedp51]

jlow

The military switched to using IMR-4064 in their long range sniper ammunition in 7.62 MK316 Mod 0 cartridge. My son works with the author of the link below and I met Fredrick in Enfield forums years ago, its a small world.

7.62 NATO Long Range Match Cartridges
By FS
PART 1

http://riflemansjournal.blogspot.com/2012/02/cartridges-762-nato-long-range-match.html

"the MK316 Mod 0 cartridge, was a Federal modified case (Drawing number 8347636), Federal match primer, Sierra 175 grain Matchking and 41.75 grains of IMR 4064 powder. According to the published sources this load will produce a muzzle velocity of 2640 fps out of a 24 inch barrel. The load as produced by Federal is claimed to produce under 1 MOA out to 1000 yards from an appropriate rifle. With the IMR powder the shift in velocity is only 20 fps from 0 to 100 Deg C, with the Standard deviation in velocity over 40 rounds being 15 fps or less. In contrast the M118LR loaded with RE-15 powder will see a 50 fps rise in velocity for a 50 deg rise in temperature."

If you read the link below he is using H4895 with his .308 loads, and H4895 is also a extreme powder like Varget.

Reloading: Western Shooters' Pet Loads for Long Range
Western Shooters' Pet Loads for Long Range
by: GS

http://riflemansjournal.blogspot.com/2010/01/reloading-western-shooters-pet-loads.html

Brass: WCC 60 or new Winchester (both weigh approx. 154 gr.), neck turned to 0.0125"
Powder: H4895 44.5 gr.
Primer: Russian LR
Bullet: Berger 175 BT, moly-coated, seated to jam 0.010"
Average Muzzle Velocity: 2835 fps
Barrel: 0.300" x 0.308", 1:11" twist, 29" long Krieger

 

[jlow]

Thanks bigpedp51 – that is interesting. I might try this in the future but at least in the short time frame, this will not work for me because I have a lot of Varget and I am sure getting that IMR-4064 nowadays would be difficult. The other problem with this setup is it is really one for a sniper i.e. shoot and forget in terms of the casing. Federal cases in my experience is notorious bad in terms of how quickly the primer pockets loosen and of course I just spend a little money buying the Lapua. The sad truth is nowadays everyone has very little flexibility in terms of trying different components unless you already have them on hand. Sad but true.