Results 1 to 13 of 13

Thread: Using magnum primers in 308 Winchester

  1. #1
    Member highestview's Avatar
    Join Date
    Nov 2007
    Location
    Haines
    Posts
    1,308

    Default Using magnum primers in 308 Winchester

    Just curious if anyone has substituted them for standard large rifle primers in the 308 Winchester. I was considering it for a load that isn't anywhere close to the max and considering the freakishly cold weather, a magnum primer might ignite the powder more like the way it should. Curious if anyone has experience, or experienced high pressure signs in the 308 with this.
    Born in Alaska: The boundary lines have fallen for me in pleasant places; surely I have a delightful inheritance. Psalm 16:6

  2. #2
    Member
    Join Date
    Jan 2007
    Location
    Southwest Alaska
    Posts
    2,145

    Default

    I have used WLRM primers in everything I reload simply because I had nothing else. I use a chronograph to check velocities. I had no problems.
    Great spirits have always found violent opposition from mediocre minds. The latter cannot understand it when a man does not thoughtlessly submit to hereditary prejudices but honestly and courageously uses his intelligence. Albert Einstein

    Better living through chemistry (I'm a chemist)

    You can piddle with the puppies, or run with the wolves...

  3. #3
    Member mainer_in_ak's Avatar
    Join Date
    Sep 2008
    Location
    Delta Junction
    Posts
    4,078

    Default

    Doesn't matter how cold the weather is, you don't need to run a magnum primer in the 308. If you want to, fine, but it isn't needed. My only load development with the 308 winchester has been with heavy for caliber loads using various 200 grain bullets. I Fired the last of them off this past winter during the 20 below zero spell. They all hit the same spot as when they were sighted in.

  4. #4
    Member highestview's Avatar
    Join Date
    Nov 2007
    Location
    Haines
    Posts
    1,308

    Default

    Quote Originally Posted by mainer_in_ak View Post
    Doesn't matter how cold the weather is, you don't need to run a magnum primer in the 308. If you want to, fine, but it isn't needed. My only load development with the 308 winchester has been with heavy for caliber loads using various 200 grain bullets. I Fired the last of them off this past winter during the 20 below zero spell. They all hit the same spot as when they were sighted in.
    I just recently decided to reload the 308 insted of run surplus/cheap 308 ammo. I was considering using the magnum primers because every other caliber I reload for is some sort of belted magnum and it would be just handy to share primers. I'm able to share powder for the 308 with my 416 Taylor.

    Will the magnum primer cause higher pressure than the standard?
    Born in Alaska: The boundary lines have fallen for me in pleasant places; surely I have a delightful inheritance. Psalm 16:6

  5. #5
    Member
    Join Date
    Sep 2011
    Location
    Fairbanks
    Posts
    466

    Default

    I tried some magnum primers with Varget in both .223Remington and .338Federal (.308Win necked up 030), from 0dF down to -30dF last winter.

    At 300 meters in .223 it didn't make a bit of difference, my groups didn't move at all switching between standard and magnum primers, all CCI, using ammuniton cold soaked out in my truck for a couple days versus warm ammunition straight from the house on multiple days at multiple ambient outdoor temperatures.

    At 200 meters in .338Federal, it didn't make a bit of difference, my groups didn't move at all switching between standard and magnum primers, all CCI, using ammuniton cold soaked out in my truck for a couple days versus warm ammunition straight from the house on multiple days at multiple ambient outdoor temperatures.


    I really, really like Varget for cold weather. I had given up on a couple other powders for .223 around 0df, and I was seeing a lot of velocity change with H4xxx in .338 Fed starting at about +15dF and just getting worse as the mercury kept dropping. I'll bump the thread when I get home to see which H4xxx powder it was, by the time I get back to this I am sure it will be too late to edit.

    Coming out the back side of winter into summer I didn't have to adjust either of those two rifle scopes at all, all year.

    Any road, I haven't ever actually loaded 308Win, but I think my data points are not totally irelevant. Different powder, different brand primer, maybe.

  6. #6
    Sponsor ADfields's Avatar
    Join Date
    Nov 2008
    Location
    Missing Palmer AK in Phonix AZ.
    Posts
    6,416

    Default

    First magnum primers arenít so much for magnum rounds as they are for hard lighting powders. In other words you donít always need a magnum primer in a 338WM and you could need a magnum primer in a 30-30 depending on the powder your using. Pick primer based on the powder your using. Hard lighting powder always needs a hot primer, hard cold lighting powder should just as well have a hot primer even if itís worm out. The exception to that would be extreme heat like 115* summer heat in Arizona where a top load with a hot primer could give problems . . . trust me, at 115*.in the sun things just want to burn!

    Then, there is often more variation between brands than between standard and magnum in the same brand. Replacing CCI magnum LR primer with standard Federal LR primer could well be going to a hotter primer. You can use whatever primer you want but always re-work the load all over new to know where you are. Never assume a primer is a primer, yea it usually is but sometimes it ainít.

    I try to only buy one brand of primer to simplify the compound multiplication effect on my inventory of adding in other brands . . . and never having the primer I need. I have also considered just buying nothing but magnums too, it would work just fine for everything but then Iíd need to rework a bunch of loads to mag primers.

    Use the magnums if you want, no problem. Just rework the load and test before you end up with lots of bullets to pull because of pressure or (more likely) groups that look like a shotgun pattern.
    Andy
    On the web= C-lazy-F.co
    Email= Andy@C-lazy-F.co
    Call/Text 602-315-2406
    Phoenix Arizona

  7. #7
    Member
    Join Date
    Apr 2006
    Location
    SwampView AK, Overlooking Mt. Mckinley and Points Beyond.
    Posts
    8,815

    Default

    AD be right.

    When ball powders are used, mag primers are in order.

    308 size case, definitely.

    IME, lighter charges, and cold weather can result in delayed ignition if you're using standard primers.

    Smitty of the North
    Walk Slow, and Drink a Lotta Water.
    Has it ever occurred to you, that Nothing ever occurs to God? Adrien Rodgers.
    You can't out-give God.

  8. #8

    Default

    FWIW, I only use Federal Magnum primers and IMR 4350 in my rifles including 243. the only exception is in my 223, I use standard primers and Benchmark, but I don't like having alot of primers and powders.

  9. #9
    Member marshall's Avatar
    Join Date
    Nov 2007
    Location
    Near Phoenix, AZ
    Posts
    1,814

    Default

    Quote Originally Posted by highestview View Post
    Will the magnum primer cause higher pressure than the standard?

    The simple answer is yes.

    Below is a link to a fairly comprehensive primer test. It's quite lengthy but good data. Towards the bottom it documents a difference of 4600 psi between the test primers.

    You can use magnum primers in place of standard primers but you really need to re-work your load from the bottom up. The increase pressure from the hotter primer will require less powder charge to achieve the same overall pressure. That increase in pressure will change your load and may result in more velocity affecting your accuracy.

    They also show that a powder charge increase to equal the primer pressure increase will produce more velocity than the increase from the primer alone. The tests show that with equal peak pressure the slower primer with more powder charge was faster than the hot primer with less powder. In other words, don't use a hot primer to achieve more pressure thinking it will give more speed. That peak increase in pressure comes at light off and is short lived. It is better to bump your charge if you are seeking more velocity assuming you have room to develop that desire.


    http://riflemansjournal.blogspot.com...mer-study.html

  10. #10

    Default

    I've been using magnum rifle primers (first Rem 91/2M, now Federal 215s) forever. I wanted to crack that magical 3000 fps mark with my 22" barrel BDL in 270 with 150g Partitions. I found a load that would shoot .5 MOA at 3030 fps a long long time ago with H4831. No high pressure signs. Been using it ever since.

  11. #11
    Member marshall's Avatar
    Join Date
    Nov 2007
    Location
    Near Phoenix, AZ
    Posts
    1,814

    Default

    Quote Originally Posted by chuckscap View Post
    I've been using magnum rifle primers (first Rem 91/2M, now Federal 215s) forever. I wanted to crack that magical 3000 fps mark with my 22" barrel BDL in 270 with 150g Partitions. I found a load that would shoot .5 MOA at 3030 fps a long long time ago with H4831. No high pressure signs. Been using it ever since.

    Wow! You're about 300fps faster than published H-4831 data with that bullet and you're doing it from a shorter barrel. I would lean heavily in the direction it's a hefty charge or a chronograph error and not the magnum primer.

  12. #12

    Default

    Quote Originally Posted by marshall View Post
    Wow! You're about 300fps faster than published H-4831 data with that bullet and you're doing it from a shorter barrel. I would lean heavily in the direction it's a hefty charge or a chronograph error and not the magnum primer.
    Look at these links, I'm about 80 fps faster than some of the loads. I'm using one more grain of powder than the handloads.com fastest load (compressed charge), magnum primers in neck sized only cases (they're a bit bigger due to fire forming). My 270 has probably shot 500 of these rounds, no ill effects. Loads have been chron'd with three different chronographs (only one of them mine) all printed just over 3000 fps for 5 shot averages.

    http://www.handloads.com/loaddata/de...=Powder&Source=

    http://www.chuckhawks.com/270win.htm

    I will say my load is a little stiffer than the handloads.com load, work up all loads slowly and stop at any signs of pressure and back off at least two grains...

  13. #13
    Member
    Join Date
    Apr 2006
    Location
    North Pole
    Posts
    296

    Default

    Speer actually specifies magnum primers for many non-magnum caliber loads.

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
  •