Graf & SonsInline FabricationRotoMetals2MidSouth Shooters Supply
WidenersTitan ReloadingStainLess Steel MediaLee Precision

Page 3 of 4 FirstFirst 1234 LastLast
Results 41 to 60 of 70

Thread: Fillers...?

  1. #41
    Boolit Master
    swheeler's Avatar
    Join Date
    Mar 2005
    Location
    Montana
    Posts
    4,415
    Quote Originally Posted by vzerone View Post
    It's a good thing to investigate further for sure. I may do a test with a 308 and 4895 if I can find my Dacron, as I don't use any light fillers anymore. Can we assume an increase in velocity with using the same componants being an increase in pressure? I do.
    Yes that is what I stated, pressure up-velocity up. My thought is dacron is doing something similar too BPI buffer but without all the friction in case transition from body to neck. I think it is sealing the bore, kind of a gas check under the gas check. Testing dacron with a powder that proves to be not position sensitive in the loading density and case tested should be proof, my thinking anyhow? If 15 grains of Unique gives 1500 fps in muzzle up-muzzle down position in 8mm case with xx weight bullet, then add 1 grain of dacron and get a 100 fps increase, where did that increase come from if it's only job is to position powder? If it is not decreasing case capacity, not increasing burn rate by friction inside the case then where is the velocity coming from? Better seal to bore
    Hell, I was there!

  2. #42
    Banned

    Join Date
    Dec 2015
    Posts
    1,481
    Quote Originally Posted by swheeler View Post
    Yes that is what I stated, pressure up-velocity up. My thought is dacron is doing something similar too BPI buffer but without all the friction in case transition from body to neck. I think it is sealing the bore, kind of a gas check under the gas check. Testing dacron with a powder that proves to be not position sensitive in the loading density and case tested should be proof, my thinking anyhow? If 15 grains of Unique gives 1500 fps in muzzle up-muzzle down position in 8mm case with xx weight bullet, then add 1 grain of dacron and get a 100 fps increase, where did that increase come from if it's only job is to position powder? If it is not decreasing case capacity, not increasing burn rate by friction inside the case then where is the velocity coming from? Better seal to bore
    I like the better seal because if you watch slow motion videos of a rifle's muzzle when fired smoke come out of it before the bullet does. So it makes sense that the Dacron is sealing things at the get go.

  3. #43
    Boolit Master
    swheeler's Avatar
    Join Date
    Mar 2005
    Location
    Montana
    Posts
    4,415
    I think we agree! Now to get Larry to test it because I'm scared to blow up my favorite mauser with dacron and bullseye!!!!!!!!!
    Hell, I was there!

  4. #44
    Banned

    Join Date
    Dec 2015
    Posts
    1,481
    Send that Mauser to me, I'll blow er up for ya!

  5. #45
    Boolit Master


    Larry Gibson's Avatar
    Join Date
    Jul 2005
    Location
    Lake Havasu City, Arizona
    Posts
    16,517
    "Some brave sole could run this kind of test with a powder that shows no position sensitivity(Unique, Bullseye, 231) in the case being tested, then add dacron and see what happens but that is usually a NONO with these powders."

    I did that many years ago in the 30-30 with Bullseye; 311291 and 5 gr BE. I didn't have the M43 PBL and was chronographing with an Oehler M35P. With out the Dacron filler, surprisingly, the most consistent load (lowest ES and SD) was with the powder forward. The highest velocity, not really by that much, was with the powder in the rear against the primer. With the powder settled in the middle of the case there wasn't a lot of difference between with the powder to the rear. When a Dacron filler was added the velocity was the highest and the ES/SD only slightly better.

    Since measuring the pressure in thousands of rounds using the Dacron filler there is no doubt it does raise pressures slightly. I discount any great effect based on "sealing the bore" because the same load sans the Dacron did not lead the bore whatsoever.....in any test. We know gas blow by causes leading yet there was none w/o the Dacron filler. In 30 cals if the bullet is sized to fit the throat, is .001 - .003 over the groove diameter and is bumped into the leade/lands how is there gas blow by anyway? If the bore is not already sealed from that then as soon as the bullet moves forward it is. The real benefit to the above test was in with the Dacron vs no Dacron the 3.5 - 4" of vertical stringing with the no Dacron load was negated at 100 yards. The load with Dacron gave groups 1/3 the size and showed no hint of vertical stringing.

    Fact is putting any inert material in the airspace between powder and bullet reduces the airspace......that in essence reduces the case volume.

    As to being "brave" (I prefer to call it "foolhardy") and repeating the test with BE why are we wanting to prove something that is already proven? A Dacron filler used, when warranted, almost always improves the ES and SD and thus improves accuracy.

    BTW; With the use of BE, 231, Red Dot, etc. up through Unique in .30 cals up through 30-06 the same accuracy improvement can be made w/o using a filler simply by drilling out the flash hole to get the primer flash into the case volume quicker and more uniformly.
    Larry Gibson

    “Deficient observation is merely a form of ignorance and responsible for the many morbid notions and foolish ideas prevailing.”
    ― Nikola Tesla

  6. #46
    Boolit Master
    swheeler's Avatar
    Join Date
    Mar 2005
    Location
    Montana
    Posts
    4,415
    We sure don't want to be " foolhardy" now do we.
    Hell, I was there!

  7. #47
    Boolit Master
    Join Date
    Sep 2012
    Location
    NE Wisconsin
    Posts
    1,010
    Larry outstanding engineering level information. Math does not lie.

  8. #48
    Banned

    Join Date
    Dec 2015
    Posts
    1,481
    If you take the little amount of Dacron you use in your load and melt it on a steel plate you get a little ball. Anything inside the case reduces it's volume even a molecule of anything. Like carbon. So yes that little piece of Dacron reduces the volume in that respect, but do you really believe that amount is to enough to make a very noticeable difference? I don't.

    Even if you bump the nose of the bullet into the leade/lands it's not totally sealing everything off, especially the grooves, yet. If you don't believe me you have to fire the rifle while filming the muzzle with a high speed camera to see the little puff of smoke come out before the bullet. There is even a little bit of gas leaking down the outsides of the case before enough pressure obturates the case and seals it to the chamber, thus the reason for sooted cases.

    Now as to whether the Dacron seals I stated in a previous post with swheeler that I agreed with him that it may. Re-thinking I don't think that is does because there just isn't enough mass there to do it. I absolutely do believe Kapok seals some as it's a whole different animal then Dacron. Long time ago I remember a few things about Dacron that I will mention here now. First the NRA said things about your bore after shooting Dacron fillers. They said about the only thing they saw was sometimes a very minute little ball of melted Dacron in the bore. The other thing is BruceB said a long time ago that he found lots of the Dacron filler laying in front of his bench. I have never found any Dacron laying on the ground in front of my bench. I've shot lots of Kapok and Dacron fillers. Watching the muzzle with Dacron I've only ever seen just smoke come out upon firing. I believe that is because the hot powder gases consume it. With Kapok I've always seen smoke and the fibers come out. The Kapok fibers coming out were as if you blew on a handful of dandelion blossums. My assumption, not proven, is that the Dacron melts from the hot powder gases and doesn't blow out the muzzle in a one piece wad or in fiber pieces. Anyone else have a take on this?

    Not arguing just the way I perseive it.

  9. #49
    Boolit Master
    swheeler's Avatar
    Join Date
    Mar 2005
    Location
    Montana
    Posts
    4,415
    Absolutely the base of the bullet has to make the trip from the expanding neck then through the throat and finally engraved by the rifling, so once inside the bore if no blow by of gases of course there will not be leading, we're talking about what happens before.
    Hell, I was there!

  10. #50
    Banned

    Join Date
    Dec 2015
    Posts
    1,481
    Quote Originally Posted by swheeler View Post
    Absolutely the base of the bullet has to make the trip from the expanding neck then through the throat and finally engraved by the rifling, so once inside the bore if no blow by of gases of course there will not be leading, we're talking about what happens before.
    Gotcha, you're basically talking about before the bullet begins to move. So have you ever found any of your Dacron filler after firing?

  11. #51
    Boolit Master
    swheeler's Avatar
    Join Date
    Mar 2005
    Location
    Montana
    Posts
    4,415
    I have found it burned around the very end of the neck, and yes I have had it blow back into my face when shooting into the wind, so I don't think it is all consumed, but most times no not on the ground in front of the bench.
    Hell, I was there!

  12. #52
    Banned

    Join Date
    Dec 2015
    Posts
    1,481
    Pretty similar to my results. Kapok sure will blow in your face if the wind blows it that way. I've found what looks like a white Teflon ring in extreme bottle neck cartridges when using large loads of hot burning surplus ball powder. That right there is conclusive proof that the BPI shotshell buffer does indeed grab the case resisting flow through the bottleneck thus increasing pressure!

  13. #53
    Guy La Pourque
    Guest
    I have another question about fillers - how do you decide if you need them, and whether they are practical? The only reason I got involved with fillers is because of hearing you guys here at Cast Boolits talking about them - but I have a Uberti 1876 repro in .45-75. I am going to try burning 40gr of 3031 in it behind a 350 grain boolit (from what little info I can find on this cartridge, I'm told that I should be able to use the mildest 45-70 load data without much worry...). Should I try fillers with this one too, in your opinion...?

  14. #54
    Boolit Master


    Larry Gibson's Avatar
    Join Date
    Jul 2005
    Location
    Lake Havasu City, Arizona
    Posts
    16,517
    Quote Originally Posted by swheeler View Post
    Absolutely the base of the bullet has to make the trip from the expanding neck then through the throat and finally engraved by the rifling, so once inside the bore if no blow by of gases of course there will not be leading, we're talking about what happens before.
    If the front drive band is larger than groove diameter it seals the bore with very little bullet movement. The base of the bullet does not need to seal the bore if the bullets entire bearing surface is larger than the groove diameter because the bore is sealed well be for the base gets there.
    Larry Gibson

    “Deficient observation is merely a form of ignorance and responsible for the many morbid notions and foolish ideas prevailing.”
    ― Nikola Tesla

  15. #55
    Boolit Master


    Larry Gibson's Avatar
    Join Date
    Jul 2005
    Location
    Lake Havasu City, Arizona
    Posts
    16,517
    Did lots of shooting on an indoor range and I've swept up lots of Dacron that accumulated on the floor in front of the muzzle. Also had it blow back in my face on out door ranges. Contrary to popular opinion I don't think much if any of the Dacron melts. I never found one spec of it melted, not on the floor of the indoor range or in the bore.

    Does a Dacron filler reduce case capacity, does the Dacron seal the bore? Fact is, neither matter simply because the use of a proper Dacron filler works as intended. The Dacron filler works better than most any other filler and as good as a couple. It is easier to use than any other filler. Thus, in my opinion based on thousands of rounds out of different rifles in a multitude of cartridges over many years, The fact that it works is whats important. I've no need to waste further time with conjecture and assumption.
    Larry Gibson

    “Deficient observation is merely a form of ignorance and responsible for the many morbid notions and foolish ideas prevailing.”
    ― Nikola Tesla

  16. #56
    Boolit Master


    Larry Gibson's Avatar
    Join Date
    Jul 2005
    Location
    Lake Havasu City, Arizona
    Posts
    16,517
    Quote Originally Posted by Guy La Pourque View Post
    I have another question about fillers - how do you decide if you need them, and whether they are practical? The only reason I got involved with fillers is because of hearing you guys here at Cast Boolits talking about them - but I have a Uberti 1876 repro in .45-75. I am going to try burning 40gr of 3031 in it behind a 350 grain boolit (from what little info I can find on this cartridge, I'm told that I should be able to use the mildest 45-70 load data without much worry...). Should I try fillers with this one too, in your opinion...?
    The decision is based on the burning rate of the powder, bullet weight and load density.

    With your 45-75 with the 350 gr cast bullet over 3031 if the load density (case capacity to the base of the seated bullet) is less than 80% then I would use a Dacron filler. I would drop back to the suggested "start" loads and work up to the intended level.
    Larry Gibson

    “Deficient observation is merely a form of ignorance and responsible for the many morbid notions and foolish ideas prevailing.”
    ― Nikola Tesla

  17. #57
    Boolit Master


    Larry Gibson's Avatar
    Join Date
    Jul 2005
    Location
    Lake Havasu City, Arizona
    Posts
    16,517
    I recently came into a quality of RL7 so I thought I would try it under the NOE 30 XCB bullet in my .308W Match M70 rifle. I initially tried 25 through 29 gr in 1 gr increments w/o a Dacron filler. The ES for those 10 shot test strings ranged from 143 fps to 248 fps.....pretty poor and the on target groups were just as poor with the best group at 2.45". Average velocities ranged from 1954 fps to 2256 fps.

    Dropping back and testing 21 gr through 25 gr with the Dacron filler (1 - 1.5 gr) velocities range from 1811 fps to 2103 fps. The ES for the 10 shot test strings dropped to 47 fps up through 103 fps. The 23 gr load with a Dacron filler averaged 1980 fps with the 47 ES and an SD of 13. The 10 shot group was .697. I loaded 25 rounds of that load and, after foulers and sighters to zero, shot 4 consecutive 5 shot CBA targets for score. The score was 194 out of 200 possible. Even though not shooting for group I measured them anyway. The average 10 shot group size was .93". Here is one of them;

    Click image for larger version. 

Name:	5 shpt group.jpg 
Views:	0 
Size:	96.7 KB 
ID:	214319

    As I said, a properly used Dacron filler works......all else is moot......
    Larry Gibson

    “Deficient observation is merely a form of ignorance and responsible for the many morbid notions and foolish ideas prevailing.”
    ― Nikola Tesla

  18. #58
    Boolit Master
    Join Date
    Mar 2010
    Location
    NC Arkansas
    Posts
    400
    Tried Dacron 1 time in 1968-69. After the first shot I pushed a small black ball of melted Dacron out of the bore. Was using a Lee Loader and a 308 Win. with Unique. Did not load any more Dacron. Loaded several with COW. It seemed to work fine. Not having access to a chrono, don't know what was actually happening but I am not going to use any more COW in a necked case.

  19. #59
    Boolit Master
    swheeler's Avatar
    Join Date
    Mar 2005
    Location
    Montana
    Posts
    4,415
    Quote Originally Posted by ulav8r View Post
    Tried Dacron 1 time in 1968-69. After the first shot I pushed a small black ball of melted Dacron out of the bore. Was using a Lee Loader and a 308 Win. with Unique. Did not load any more Dacron. Loaded several with COW. It seemed to work fine. Not having access to a chrono, don't know what was actually happening but I am not going to use any more COW in a necked case.
    Oh ya it can and does melt upon firing, I find it often melted around the very end of the neck, hard and can be scraped off by fingernail. Most recently with 24.0 Grs IMR 4198 and .8 gr dacron. I have never used dacron with any powders with a burn rate faster than 2400 speed.
    Last edited by swheeler; 02-17-2018 at 12:13 PM.
    Hell, I was there!

  20. #60
    Banned

    Join Date
    Dec 2015
    Posts
    1,481
    Quote Originally Posted by swheeler View Post
    Oh ya it can and does melt upon firing, I find it often melted around the very end of the neck, hard and can be scraped off by fingernail.
    I believe you when you say it melts. The NRA said it melts and they found little round ball/balls of it in the bore. Myself I have never found that. I think because I'm not one to shoot the very small charges of fast powders like Bullseye and Unique, that I've always leaned towards the heavier loads, when I use to use Dacron it got blown out of the barrel and pretty much obliterated and I never found any in front of the bench. My loads blew everything out of the barrel.

    I don't feel that swheeler and myself are making conjectures and assumptions. Our statements are founded on our shooting tests and experiments. I've also found because I don't shoot the "peep squeak" loads that I've no need for a Dacron filler. I've gotten good accuracy and single digit ES's and SD's even with the slow burning surplus powder duplexed with booster loads. I'm not mocking any of you that like and use those light loads, but I have no need for them. Almost all my loads fill a high percentage of the case and the duplexed surplus powder loads feel it 100% all the time.

    How can anyone be positive that there is no gas leakage with the bullet being jammed into the throat and cone/leade, as mentioned somewhere else in this thread, without a high speed camera at the muzzle?

Page 3 of 4 FirstFirst 1234 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Abbreviations used in Reloading

BP Bronze Point IMR Improved Military Rifle PTD Pointed
BR Bench Rest M Magnum RN Round Nose
BT Boat Tail PL Power-Lokt SP Soft Point
C Compressed Charge PR Primer SPCL Soft Point "Core-Lokt"
HP Hollow Point PSPCL Pointed Soft Point "Core Lokt" C.O.L. Cartridge Overall Length
PSP Pointed Soft Point Spz Spitzer Point SBT Spitzer Boat Tail
LRN Lead Round Nose LWC Lead Wad Cutter LSWC Lead Semi Wad Cutter
GC Gas Check