Results 1 to 7 of 7

Thread: rl19 instead of n550

  1. #1

    rl19 instead of n550

    these have very similar burn rate do you think i could use rl19 as an alternative so long as i start with a slightly reduced load? any advice would be good thanks

  2. #2
    No-one can categorically answer your question - not enough info for even a rough guess - calibre & bullet etc????
    Generally similar burn rates usually mean that similar performance is possible ---- BUT as always you should do your own load development - for your rifle working up the load as normal based on the powder manufacturers' data for your starting point.
    I use Reloder 15 & 22 - not 19 though -- good reliable powder providing excellent velocities & accuracy.
    There is no guaranteed short cut although QuickLoad can give pretty good guide lines to support published data.

    LOAD SAFE - LIVE LONG

    Ian

  3. #3
    That would depend on slightly..

    The Lapua burn rate chart shows them as being equivalent, but that doesn't mean that the loads will be the same to produce the same pressure and velocity. I'd find the maximum RL19 load for my bullet then start at the suggested starting load (or 10% below maximum if there's no starting load), working up slowly towards the maximum while checking for pressure signs, as if I was using a new powder with a different burn rate.

  4. #4
    SD Regular
    Join Date
    Dec 2008
    Location
    East Midlands M1/M69 Junction 21
    Posts
    5,402
    Burn rate charts are like the famous topographical map of the London Underground.

    It may SHOW two stations close together...yet in real life they may not be as close together as the thing appears to show...that's how I treat them.

    On another aside, blackpowder has a slower burn rate than smokeless. Yet the pressure curve is very different. Which is why black powder was used for provisional proof of shot gun barrels as it gave pressure for the full length of the tube and not just at the breech area.
    Last edited by enfieldspares; 11-08-2014 at 06:20.

  5. #5
    Quote Originally Posted by enfieldspares View Post
    Burn rate charts are like the famous topographical map of the London Underground.

    It may SHOW two stations close together...yet in real life they may not be as close together as the thing appears to show...that's how I treat them.
    I agree.

    Also since we know that many powders are exactly the same stuff, but re-labelled between manufacturers, it's surprising how many are still shown on the burn rate tables as having different burn rates.

  6. #6
    Quote Originally Posted by HSB View Post
    these have very similar burn rate do you think i could use rl19 as an alternative so long as i start with a slightly reduced load? any advice would be good thanks
    That depends on a lot of things, beginning with the cartridge and bullet weight. You cannot just make a blanket statement of equivalency based on one factor, Relative Burn Rate. There are a lot of other factors where the two powders may differ:

    * Ignition characteristics - one may need a hotter primer to light it up properly
    * energy per weight, expressed in foot-lbs of pressure per grain of powder weight
    * sectional density of the powder
    * how much of the energy is lost to heat, because double base powders with the same burn rate may have different percentages of nitroglycerin.

    So, yes, you can start with a reduced load of RL-19 and work up, but the best way is to have some known loads of N-550, at a known velocity, and when you ( and if) you reach that same load with RL-19, you can start building a chart. Ideally, you would have the starting and workup loads of N-550, and walk up the RL-19 with the chronograph to compare velocities.

  7. #7
    thanks for your help , i have sme data for the 550 so plan to try and work up a load from that but just wanted to be sure starting 10% or so lower was the right thing to do with them being different powders! thanks again

Similar Threads

  1. Viht N550
    By pablo.222 in forum Ammunition, Reloading & Ballistics
    Replies: 7
    Last Post: 28-03-2014, 15:08
  2. RL19 + 90gr Nosler Ballistic Tip
    By NellyT in forum Ammunition, Reloading & Ballistics
    Replies: 7
    Last Post: 26-03-2014, 16:34
  3. For Sale n550 digisight
    By waggy 1 in forum Optics
    Replies: 11
    Last Post: 18-03-2013, 22:23
  4. For Sale Pulsar N550
    By bogwelly in forum Optics
    Replies: 5
    Last Post: 08-10-2012, 19:42
  5. pulsar n550
    By bogwelly in forum Equipment & Accessories
    Replies: 2
    Last Post: 25-02-2012, 14:17

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •