RL-17 vs H4350 and temperature variance

Discussion in 'Reloading' started by stanley52, Jan 24, 2013.

  1. stanley52

    stanley52 Well-Known Member

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    Ok so there is COMPLETELY conflicting information all over the internet about RL-17 and whether or not it is temperature stable. They claim it is, and some agree; however, many others do not. Most people who claim it is fairly variable with changing temperature agree that it changes about .8fps per 1 degree Fahrenheit of temperature change . I have also read that if you keep chamber pressures high (hot loads) then it stabilizes the powder. Can anyone confirm any of this? One last remark, if RL-17 is truly a temperature unstable powder, how much more so than H4350? Is it a big enough difference between the two powders to matter?

    I am getting ready to receive a custom 260 with a 24" benchmark barrel with an 8.5" twist, if anyone is curious as to what this information will applied towards.
     

  2. Bullet bumper

    Bullet bumper Well-Known Member

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    I don't have specific data on Rel 17 but this may give you some guidance.
    There is only one true line of powders that have a low temp sensitivity compared to the others. Some are fairly similar.
     

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  3. Lefty7mmstw

    Lefty7mmstw Well-Known Member

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    If you throw in h4895 with it's 100 fps swings in my 25wssm between 20 degrees f and 90 degrees f and you've got a different ballgame. I put NO stock in the hodgdon temp. stability; I've seen otherwise with the few I do use. I'll play with Retumbo soon in a couple of my rifles and I do expect at least slightly better results as it isn't a revision of an older powder like some of the older Hodgdon flavors.
     
  4. kaseyfied

    kaseyfied Well-Known Member

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    their is a easy way to find out.. and I have done this with ALOT of powders.. once yo find a load.. make up 10 rounds.. put 5 in a cooler.. and shoot the other 5.. you will see if its temp stable or not.. I have never found a hogden powder that hs 200fps difference in temp enviornments. I have hunted colorado, montana and oregon in some cold and hot conditions and never had problems with h1000, retumbo, h4350 and h4821sc.. I recently just tried rl19 in my 270 wsm.. shot it the first day in 40 degree weather.. not bad accuacy and velocities.. shot same load 3 days later in 27 degrees and it was all over the place.. velocities varied up to 65 fps.. and accuracy went out the window!! some have said rl is nottemp sensitive at all and who knows...I have always had very good luck with the cooler trick.. just put some on ice for 20 minutes.. and shoot the others if you can in around 70-80 degree weather.. gunwerks uses hodgden powder for their ammo and it works great for 0 degres to 90.. just my 2 cents though!

    kasey
     
  5. Lefty7mmstw

    Lefty7mmstw Well-Known Member

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    It seems some loads in the 270 wsm are flakey with rl19; my dad had that trouble years ago with his 270 wsm and even other powders didn't really cure its ills. He eventually traded the rifle. My 300 win varies less than 60 fps real world with rl22 and 165's, and is a solid 1/2 moa rifle at any temp. with it. Same story with my 300 rum and rl25 and rl50. Can't say for sure yet on rl33 but it looks promising. I think it's often a load right on the edge of being ballistically stable, ie. a bit cold or hot on the primer or a bit cold or hot on the pressures that kills the rl powders at times. At one temp. it's fine but you swing a bit and it gets buggy; I've seen it with 7828 and 140's in the 7rem too. At 60 f or warmer my 7rem loves 7828, but you cool down much and it goes from a 1/2 moa load to a 2 moa load. You have to prove your load in real world conditions and not hang your hat on a slogan.
     
  6. Popapi

    Popapi Well-Known Member

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    TAG
     
  7. kaseyfied

    kaseyfied Well-Known Member

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    S Well that load shot.344 at 250 yrds 5 trips to the range.. or better..the load was not flaky at all..
     
  8. Bullet bumper

    Bullet bumper Well-Known Member

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    You don't know what you are talking about. The following Hodgdon powders are made by ADI in Australia with special technology not well known to others. Temperature information comes from ADI not Hodgdon .
    H4227
    H4895
    H4198
    VARGET
    H4350
    H50BMG
    H4831
    H4831SC
    H1000
    RETUMBO
    H322
    Benchmark

    So they all have the same technology as Varget .
    Wether any figure is correct or not these powders are proven to have less temp sensitivity than others on the market .
     
  9. diriel

    diriel Well-Known Member

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    I have some RL17 for my 6.5x55 swede and I can Definitely say it is temp sensitive. I have to admit for fair weather stuff it can be pretty nice though. It really just depends on what you are doing.
     
  10. kaseyfied

    kaseyfied Well-Known Member

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    The cooler test is a "real world" proven method.. if u think 60 fps variant in a load is good then i dont know what to tell u.. thats between 8-10 inches of error at 1k not counting human.. i would never be happy with any load that has a 60fps swing... i dont settle for anything over 18fps swing
    ... thats why ibuse hodgden powders.. they work.. i think.somethings just wrong.with the.load ur using.. just cus its a half minute load doesnt meam its the best load..
     
  11. Lefty7mmstw

    Lefty7mmstw Well-Known Member

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    I've seen 100 fps change with THE SAME BOX of 25 WSSM'S loaded with H4895;
    YOU do not know what you are talking about. I shoot over an Oehler 35p chrono.
     
  12. Lefty7mmstw

    Lefty7mmstw Well-Known Member

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    The cooler method doesn't take into account the changes in barrel stiffness or dimension when the temp. changes. I'm killing to 600 yards offhand with my 300 win; good enough for me.
     
  13. kaseyfied

    kaseyfied Well-Known Member

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    Maybe being shakey makes the load more accurate:) barrel stiffness has nothing to do with the powder itself myfriend.. if barrel stiffness was such a huge deal then no powder would work well in diffferent temp enviornments.. just my 2 cents i guess.. all i know is a shoot a hell of a long way sometimes in 5 degree weather and my velocities are damn near identical with my 90 degree shootin..
     
  14. Lefty7mmstw

    Lefty7mmstw Well-Known Member

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    I could have a more constructive conversation with a deaf mute than we are having here. Ii've seen a certain amount of vel. spread with ALL powders. Good day.