'Soft' Primers

Discussion in 'Technical Questions & Information' started by CountryGunsmith, Feb 24, 2003.

  1. CountryGunsmith

    CountryGunsmith New Member

    Jan 29, 2003
    Deep Piney Woods of East Texas
    V.I.P. Member
    Posts: 368
    (10/29/02 10:35:54 pm)
    Reply | Edit | Del All So tell me about 'soft' primers
    reading some tales of slamfires, 'soft' primers mentioned as possible cause, wth? Is there such a thing (in the last 20-40yrs)?
    Reloading for ~15yrs, and I've never come across anything about this with modern components.

    V.I.P. Member
    Posts: 383
    (10/30/02 8:34:14 am)
    Reply | Edit | Del Re: So tell me about 'soft' primers
    Here's my take on it: in my experience with 7.62x39 ammo in SKS's, the milsurp stuff uses Berdan primers. These are military spec primers. They can withstand harder conditions, as in military use. The new production American ammo uses softer primers (i.e. thinner metal on the cap), which tends to sometimes slam-fire when the rifle chambers a new round. This is caused by the inertial tap of the firing pin as the bolt slams into battery.

    The milsurp primers can take this tap with no problem. But the softer primers are being detonated by the tap. If you load two rounds and only fire the first one (but let the second one be chambered), you can eject the second unfired round and look at the primer. You will most likely see a dent in the primer from this inertial tap. This is normal, at least for an SKS. It shouldn't set off the round with milsurp ammo or any ammo that uses mil-spec primers. IMHO the American manufacturers need to do a little more testing before selling this stuff for use in semi-auto rifles.
    Macht kaputt, was euch kaputt macht!

    gun runner john
    *TFF Staff*
    Posts: 704
    (10/30/02 1:35:03 pm)
    Reply | Edit | Del Re: So tell me about 'soft' primers
    Federal primers are considerably softer than CCI primers. I've loaded with both, and never experienced any problems. I've had old guns that will misfire with CCI primers, but function 100% with Federal primers. Some competition shooters that liked to lighten the hammer springs on their revolvers would shoot Federal primers exclusively because they'd get reliable ignition at lighter spring tensions than other primers.

    I've loaded .223 with both Federal and CCI, and if you examine a round after it's been chambered, the Federal does indeed have a larger "dimple" from the firing pin inertia. OTOH, I've never had them slam-fire, and I don't lose a lot of sleep worrying about it.

    V.I.P. Member
    Posts: 369
    (10/30/02 2:55:28 pm)
    Reply | Edit | Del Re: So tell me about 'soft' primers
    1952 - is that SKS issue one of softer primer metal, or one of 50yr-old springs? ( )

    Thanks, both of you, that's the kind of anecdotal info I'm seeking.

    *TFF Senior Staff*
    Posts: 1410
    (10/30/02 3:43:24 pm)
    Reply | Edit | Del Re: So tell me about 'soft' primers
    Only difference in primers that I've been aware of is that pistol primer cups are softer than rifle cups, due to the softer hammer fall on handguns.
    "Keep Off The Ridgeline"

    V.I.P. Member
    Posts: 57
    (10/30/02 4:29:17 pm)
    Reply | Edit | Del Re: So tell me about 'soft' primers
    Can't tell you about soft primers but I bought a few cases of British 9M/M MarkIIz made in 1944, a few years back, that has very hard primers. This stuff was for 9mm SMGs that fired from an open bolt such as the various STEN guns, Lancasters, etc. I bought it to use in open bolt SMGs and it works fine. It won't work in Beretta's, Glocks or S&W 9s. I've found that it will function in Canadian Inglis HPs.
    If you believe it is reprehensible to possess the will and means to repel a criminal assault...how can you rightfully ask another to risk his life to protect yours?
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