Soft primers/easy slam fire?

[Tactical30]

I heard if you use soft primers such as Federal Match you can have easy slam fires. True?
I have been reloading with Federal match primers for awhile in my AR-15 and had no slam fires. Im just wondering if this is true or not if so which primers are the soft ones?
Anyway I would only be worried about it if I had a floating primers such as a AR-15,M14 etc. Now that I posted this the first time i go to the range again im going to have a slam fire! Ill be pissed!

 

[kchu02]

Re: Soft primers/easy slam fire?

It all depends on the AR. Honestly some people have problems and some people don't, for soft primers. I think Winchester ones are the softest (correct me if i'm wrong).

Hardest ones are CCI 41 - these are made for AR15, they are labeled as for 5.56 NATO rounds. CCI 450 (Small Rifle Magnums) are also harder, but you would have to decrease your current load a bit to replicate same velocity. Overall I think CCI primers are rated slightly harder, even their regular Small Rifle (CCI400) Primers. I've never had a problem with them, so I really never tried Federals or Winchester primers. I currently use CCI 450 and haven't had a problem yet (I run it out of a Colt 6920)

 

[EddieNFL]

Re: Soft primers/easy slam fire?

I've used tens of thousands of Fed (standard and match) primers without issue (knock on wood). More recently I've used Wolf, which I think are softer than Fed. So far, so good.

 

[427Cobra]

Re: Soft primers/easy slam fire?

I have used about 3k of Winchester WSR primers in my AR's with no problems what so ever, I not saying a slam cannot happen, but I have never seen one, I think this is a somewhat false rumor.

 

[Greg Langelius *]

Re: Soft primers/easy slam fire?

IMHO, slamfires (which I have neither witnessed, nor had related to me by someone I personally know) are less a matter of primer composition, and more a matter of shooter technique.

Semis should never be hand chambered, i.e. the round hand fed into the chamber, then the bolt released to slam home.

The round should be fed into the magazine, then the bolt released to strip the round out of the mag, fed, and the bolt enter battery the way the system was designed. This incorporates the deceleration forces inherent in the magazine feeding process, keeping the inetria of the firing pin below the degree of force necessary to trigger a primer.

Although nothing is impossible, a properly handled firearm should not slamfire.

Military primers hardness specs are intended to protect soldiers from their own stupidity and willful defiance of painfully repetitious firearm and ammunition handling instructions. Our government values its soldiers' well being, regardless of their degree of inherent and willful stupidity, above ideal ammunition accuracy capability.

Greg

 

[treebasher]

Re: Soft primers/easy slam fire?

"CCI® No. 34 and No. 41 MILITARY RIFLE PRIMERS

Military-style semi-auto rifles seldom have firing pin retraction springs. If care is not used in assembling ammunition, a “slam-fire” can occur before the bolt locks. The military arsenals accomplish this using different techniques and components—including different primer sensitivity specifications—from their commercial counterparts. CCI makes rifle primers for commercial sale that matches military sensitivity specs that reduce the chance of a slam-fire when other factors go out of control*. If you’re reloading for a military semi-auto, look to CCI Military primers.
*Effective slam-fire prevention requires more than special primers. Headspace, chamber condition, firing pin shape and protrusion, bolt velocity, cartridge case condition, and other factors can affect slam-fire potential. "

http://www.cci-ammunition.com/products/primers/primers_prod.aspx?id=30

Now here is the thing, I have NEVER used these military primers in any of my AR's and have even used CCI benchrest primers without issue. Could a slam fire happen? Of course it could. Likelihood of it happening? Who knows but my guess is pretty slim.

Let the bolt go home on a round sometime at the range and then extract it. You WILL see a light firing pin hit on the primer. Match primers are more sensitive than standard primers and that is why it is recommended that a less sensitive primer be used.

 

[MAUSER88]

Re: Soft primers/easy slam fire?

I use Winchester primers exclusively in my AR. Never had a slam fire in over 10,000 reloaded rounds.

 

[Natep]

Re: Soft primers/easy slam fire?

I dont think that a slam fire has as much to do with a soft primer as one might think. Probably an issue with the weapon. Im also inclined to believe that primers are so similar in the material composition of the cup that the difference will never have a measurable effect on performance.

 

[EddieNFL]

Re: Soft primers/easy slam fire?

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">I think this is a somewhat false rumor.</div></div>

It may not be common, but it does happen. I've witnessed one.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Semis should never be hand chambered, i.e. the round hand fed into the chamber, then the bolt released to slam home.</div></div>

A very common practice at HP matches. In fact, I've never seen anyone load differently during slow fire stages. Several companies offer magazines and followers just for hand chambering.

 

[Greg Langelius *]

Re: Soft primers/easy slam fire?

I won't dispute that common practice involves what I would personally consider risky technique. My reasons for favoring mag feeding are a direct consequence of instuctions I received in Boot Camp.

When I see it at matches, I pretty much just cringe and bite my tongue; I don't want to get preachy in the middle of a match. Better to lead by example, I feel.

It does not surprise me at all that you have witnessed (a) slamfire(s), I'm thinking you're surrounded with a higher probability.

I learned to shoot H/P N/M with a Garand and a SLED. I also owned and fired an M1A and an AR in the same kinds of comps, but am currently back to a Garand/SLED-only status.

I don't shoot a lot of N/M these days, and my only remaining semis are the Garand and a 20ga shotgun.

I remain convinced that slamfires are significantly less likely with mag feeding.

Greg

 

[gun-rx]

Re: Soft primers/easy slam fire?

I suppose that this reply will show age on my part, but here goes. I carry a scar on my right palm from 13 stitches due to a slam fire back in the 80's. The rifle was a Match Grade M-1 Garand. Shooting NRA highpower requires 22 shots slow fire from 200 yds in the first stage. Loading a Garand single shot is no monumental task, but here is how it all happened.
While shooting the offhand stage, I was at my 6th shot for record with everything going fine. I slid #6 into the chamber, depressed the follower to allow the bolt to run home, and turned loose of the op rod. The bolt moved forward until it hit the rear of the follower and stopped. This is where i made my mistake. Rather than using my thumb to pop the op rod handle, I opted to bump it with the palm of my hand. Upon closing and partially locking into battery, the firing pin tapped the primer and ignited it. The op rod handle slammed into my palm and opened it up like a sardine can. Wrapped up the hand, went to the saw bones, and 13 stitches later I a fixed man.
That year I personally witnessed 2 other slam fires in matches. All with M-1 garands, and all using Federal 210M primers. One of the other guys has a scar identical to mine, the other person was smarter and got his meat hook out of the way. I notified Federal at the time of my accident to see if they had changed anything in their primer cups. They wanted me to send my rifle back for inspection, but I declined since I was shooting matches with it. Later that year I see an article in American Rifleman about how they had thickened their primer cups due to this problem.
I've never heard of slam fires on M-1A's, M-14's, or Ar's, but feel that it's allways a possibility. After my incident, I learned to allways bump the op rod with my thumb, palm up. That way all meat is out of the way.
You can readily tell if a Garand has ever slam fired. When it happens, it blows the windage knob clear off the sight and removes the top corner of the right locking lug recess in the receiver. I hope I've cleared this up for some. Kevin

 

[Shady_Jay]

Re: Soft primers/easy slam fire?

I used G210M primers in a M1A and I had slamfires

match primers in a AR-15 have never slamfired

Armalite AR-10 with firing pin equipped with spring = dented primer cup with no ignition until hammer dropped

 

[CavalrySoldier3ACR]

Re: Soft primers/easy slam fire?

If you are worried about slam fires in an AR platform, you can try the lighter titanium firing pins. Since they are lighter, there is less inertia when the bold closes and they bump the primer, but still are rigid enough to function when the hammer falls on them.

 

[general_purpose]

Re: Soft primers/easy slam fire?

I've been using Winchester for years and several thousands or rounds in my three AR's. I've had dimpled primer cups, but never had any slamfires.

 

[Greg Langelius *]

Re: Soft primers/easy slam fire?

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Semis should never be hand chambered, i.e. the round hand fed into the chamber, then the bolt released to slam home.
</div></div>

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">While shooting the offhand stage, I was at my 6th shot for record with everything going fine. I slid #6 into the chamber, depressed the follower to allow the bolt to run home, and turned loose of the op rod. The bolt moved forward until it hit the rear of the follower and stopped. This is where i made my mistake. Rather than using my thumb to pop the op rod handle, I opted to bump it with the palm of my hand. Upon closing and partially locking into battery, the firing pin tapped the primer and ignited it. The op rod handle slammed into my palm and opened it up like a sardine can. Wrapped up the hand, went to the saw bones, and 13 stitches later I a fixed man.
</div></div>

...I rest my case...

Greg