Anybody know a temperature stable powder with a similar burn rate as Retumbo

Discussion in 'Reloading' started by mtbfarms, Nov 27, 2012.

  1. mtbfarms

    mtbfarms Member

    Messages:
    9
    Joined:
    Feb 22, 2012
    I have been using Retumbo with some pretty good accuracy, but I found it is inverse temperature sensitive. Velocity goes down as the temp goes up.

    Any suggestions?
     
  2. KevinRohrer

    KevinRohrer Member

    Messages:
    6
    Joined:
    Feb 5, 2010
    Yes, do an internet search for "smokeless powder burn rate chart", and you will get the answer to your question.

    Burn Rate
     

  3. mtbfarms

    mtbfarms Member

    Messages:
    9
    Joined:
    Feb 22, 2012
    I have the burn rate charts. I was wanting to know if anybody knew of a more temp stable powder
     
  4. edge

    edge Well-Known Member

    Messages:
    1,088
    Joined:
    Nov 4, 2005
    Inverse, sounds crazy :)

    You need to give more data.
    Are you near 100% case fill?
    What caliber?
    What bullet?

    Powders act differently in different situations, that is why there is so much discrepancy in burn rate charts!

    Hodgdon Retumbo is supposed to be less temperature sensitive and they designate it as an Extreme Power, LOL.

    edge.
     
  5. B23

    B23 Well-Known Member

    Messages:
    1,104
    Joined:
    Oct 30, 2008
    Edge is 100% correct.

    I used to think the powder burn rate chart was non variable and etched in stone. After talking to Hodgdon some time back, I learned this wasn't the case at all. Hodgdon told me the chart was just kind of a general guide and that a powders burn rate was not a constant and the burn rate could change every time a new variable was introduced. He said many powders are close, sometimes, even very close but to never think you can substitute one powder for another based on the burn rate chart.
     
  6. Tikkamike

    Tikkamike Well-Known Member

    Messages:
    4,350
    Joined:
    Dec 26, 2009
    H1000 is very close
     
  7. jhibbard24

    jhibbard24 Well-Known Member

    Messages:
    158
    Joined:
    May 20, 2010
    i know H1000 is supposed to be very insensitive to temp. i dont have any first hand experience with it tho.
     
  8. jmden

    jmden Well-Known Member

    Messages:
    2,725
    Joined:
    Nov 2, 2003
    Both Retumbo and H1000 are in the Hodgdon family of Extreme powders, the hallmark of which is greater temperature insensitivity than most other powders out there:

    Extreme Rifle Powders

    That being said, as some have said already, many find that H1000 has a very close burn rate to Retumbo and many say 'there's nothing Retumbo does that H1000 won't do at least as well' and some seem to thing that H1000 is more consistent in some respects (especially when approaching max loads) than Retumbo.

    Lots of variables here in individual rifles and how reloaders 'do' their craft.

    I have not used H1000. I've always had Retumbo be the reccomended powder between the two for the rifles I use it for, so I honestly wonder if there is any difference at all between the two powders, save kernel size, for Hodgdon to have there be a change between the two to say that one burns slower/faster than the other. Is there a difference in kernal size? Tons of folks here use these two powders to get a combination of decent velocity and consistent performance at LR in somewhat varying temperatures.

    How large a temp change did you use it in?
     
  9. mtbfarms

    mtbfarms Member

    Messages:
    9
    Joined:
    Feb 22, 2012
    I'm using retumbo in a high performance .416 muzzleloader. Pushing a 375g cutting edge copper @ 2805 fps at 25f and 2745 fps at 70f. The hotter the slower. Colder faster. I'm getting great accuracy just don't like the velocity change with temp.
     
  10. ar15topgun

    ar15topgun Member

    Messages:
    10
    Joined:
    Nov 13, 2012
    My gunsmith is using IMR4198 in his .45cal custom smokeless m/l 285 and 327 gr bullets.
     
  11. alaska

    alaska Well-Known Member

    Messages:
    619
    Joined:
    Feb 1, 2010
    New Reloader 33

    New Reloader 33

    Military has bought a big shipment for the 338 lapuagun)
     
  12. Lefty7mmstw

    Lefty7mmstw Well-Known Member

    Messages:
    4,280
    Joined:
    May 13, 2012
    Re: New Reloader 33

    good stuff-- rl33
    It was too windy to chrono when I went out and tried some but it was as accurate as rl50 in the 300 rum with 225 hornady. Gotta get to the range after critter getting season is over.
     
  13. edge

    edge Well-Known Member

    Messages:
    1,088
    Joined:
    Nov 4, 2005
    OK, as a guess you must be in the 140-150 grain range with that load.
    Unless you have powder cavity larger than the bore diameter that powder column will be about 4 3/4 inches long.
    Being a "straight case" it is hard to maximize efficiency.

    Have you played with different primers?
    If you switch to H1000 you will need to reduce the load to keep the pressure about the same and then your velocity will almost certainly be a bit lower too.

    Personally if the load is accurate at the temperature extremes I would add the info to my database and just adjust!

    Summertime you add whatever clicks are needed to compensate for the 60fps and shoot.
    You will have more variation than that when you go up/down a few thousand feet or shoot during a low/high pressure system...IMO.

    edge.
     
  14. mtbfarms

    mtbfarms Member

    Messages:
    9
    Joined:
    Feb 22, 2012
    There is a powder chamber that is larger than the bore.
    I have some h1000 on order. It tested about the same pressure as retumbo with a little higher velocity.