Results 1 to 7 of 7

Thread: Magnum Primer experiment in 300 Win Mag

  1. #1
    Member Float Pilot's Avatar
    Join Date
    Oct 2006
    Location
    Kachemak Bay Alaska
    Posts
    4,218

    Default Magnum Primer experiment in 300 Win Mag

    It would appear that brands do make a difference.

    300 Win Mag. Rem M-700 XCR Tactical 26 inch bbl.

    200gr Sierra Match King
    78.0 grains RL-25
    WW brass trimmed to 2.610,
    3.470 COL NO Crimp.
    Temp 20f, wind 15 knots. 100 yards

    Remington 9 ½ mag primer = 2,930 fps & a 1.4 inch group

    Winchester Mag primer….. = 2,995 fps and a 1.1 inch group

    CCI-34 Military Primer….. = 3,014 fps and a 0.80 inch group

    Federal 215 Match Primer.. = 2,990 fps and a 0.55 inch group

    CCI-250 mag primer =….. = Chrono failure and a 0.75 inch group
    Floatplane,Tailwheel and Firearms Instructor- Dragonfly Aero
    Experimental Hand-Loader, NRA Life Member
    http://site.dragonflyaero.com

  2. #2
    Member kodiakrain's Avatar
    Join Date
    Jan 2010
    Location
    Kodiak, Ak
    Posts
    3,175

    Default Thanks for posting

    Wow, that's good info thanks for posting all that work

    Unfortunately I bought a bunch of Rem 9 1/2's already...

    Ever done experiments with Mag vs reg Lg rifle? I have a Speer book that actually recommends CCI 200's for .270wsm when all the other books I have seen say CCI 250's for everything, so of course I got some 200's to experiment!?!

    Not much idea what I'm doing yet but thought maybe they would work for loading down to 90 gr bullet -Varmint load? I guess I'll use them somehow,

    Tried 20 so far but haven't done the comparison yet to 250's

    Any idea ahead of time what I'll see? What would you guys do with that idea?

  3. #3
    Member Float Pilot's Avatar
    Join Date
    Oct 2006
    Location
    Kachemak Bay Alaska
    Posts
    4,218

    Default

    In some cases the regular primer will work better than the magnum... It depends on the cartridge, powder and temp.

    Today I tried regular WLR primers in my 350 Rem Mag and WLR-Magnums. The Magnums gave me 50 fps more velocity and gave me a tighter group.
    1.0 vs 2.0 inch

    In my 6.5x55 Swedes, 7x57 and 30-06 loads, the mag primers are faster, but much less accurate.
    Floatplane,Tailwheel and Firearms Instructor- Dragonfly Aero
    Experimental Hand-Loader, NRA Life Member
    http://site.dragonflyaero.com

  4. #4

    Red face

    Quote Originally Posted by Float Pilot View Post
    It would appear that brands do make a difference.

    300 Win Mag. Rem M-700 XCR Tactical 26 inch bbl.

    200gr Sierra Match King
    78.0 grains RL-25
    WW brass trimmed to 2.610,
    3.470 COL NO Crimp.
    Temp 20f, wind 15 knots. 100 yards

    Remington 9 ½ mag primer = 2,930 fps & a 1.4 inch group

    Winchester Mag primer….. = 2,995 fps and a 1.1 inch group

    CCI-34 Military Primer….. = 3,014 fps and a 0.80 inch group

    Federal 215 Match Primer.. = 2,990 fps and a 0.55 inch group

    CCI-250 mag primer =….. = Chrono failure and a 0.75 inch group
    My handloading mentor told me if I needed to use magnum primers to use Federal 215's "cause that is what was designed to fire the Weatherby's". Early on I was caught up in "magnumitis" and shot several Weatherby mag's and used 215's in them exclusively and never had an issue.... He was long on common sense and short on diploma's, but man could he turn out accurate hand loads. He's gone now, but wish I had asked more questions while I could......

    I still use Federal 215's, and they still work great

  5. #5
    Member
    Join Date
    Jul 2009
    Location
    MN
    Posts
    739

    Default How many were shot?

    Float,
    How many rounds were shot to get those "averages"? The more rounds with each primer, the more valid the test. Fed 215 are the hottest for the reason previously mentioned. However I would trade accuracy for 100 fps more velocity any day.

  6. #6
    Member Float Pilot's Avatar
    Join Date
    Oct 2006
    Location
    Kachemak Bay Alaska
    Posts
    4,218

    Default

    15 each. Three groups of five shots each type.
    This rifle is still not as accurate as I wish.
    Floatplane,Tailwheel and Firearms Instructor- Dragonfly Aero
    Experimental Hand-Loader, NRA Life Member
    http://site.dragonflyaero.com

  7. #7
    Member
    Join Date
    Aug 2007
    Location
    Eureka MT
    Posts
    3,048

    Default

    I think there are too many variables to say different primers will make a difference. I am sure they will in some cases but just as sure they won't in other cases. Powder type, case volume, bullet weight and caliber, barrel length and other things all have an affect on wheather the primer will make any real difference or not.

Bookmarks

Posting Permissions

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