Federal AR Match Grade Primers GM205MAR

[SS427]

Are Federal AR match grade primers SKU:GM205MAR pretty much the same as Federal match grade small rifle primers SKU: GM205M?

 

[Buzz]

In theory the cups are harder to avoid slam fires.. in reality, who knows. I use Wolf SRM and have yet to have any issues. They're coming back into stock at retailers now, might want to give them a try.

 

[stool]

and it is next to impossible to get a slam fire in an ar.
drop a loaded rifle from 2 or 3 stories up muzzle down ..maybe the mass of the firing pin will set off the primer.

in bolt closing, the geometry prevents the fp from moving forward till the bolt lugs are engaged.....there is a reason the carrier has the angled cut for the guide pin....

 

[37Lincoln1]

and it is next to impossible to get a slam fire in an ar.

No, it is not.

 

[afrench]

and it is next to impossible to get a slam fire in an ar.

with federal primers, it's very possible. i've seen it with others and have experienced it myself until i switched to something with a harder cup.

 

[Buzz]

and it is next to impossible to get a slam fire in an ar.
drop a loaded rifle from 2 or 3 stories up muzzle down ..maybe the mass of the firing pin will set off the primer.

in bolt closing, the geometry prevents the fp from moving forward till the bolt lugs are engaged.....there is a reason the carrier has the angled cut for the guide pin....

It's enough to dimple some primers. Would it be enough to set off a primer known for soft cups? I don't know, but I'm not going to be the guinea pig. The wolf primers perform well and are a few bucks cheaper.

 

[gtl1946]

Don't ever think it's impossible that a slam fire is impossible with AR's . Thru my own stupidity with an improperly seated FLUSH primer rather than slightly ressesed primer I ended up with a blown mag. and a reformed "belted .223 case and an open bolt . Stupidity got my attention !!!! If you eject a chambered but non fired round you will see a slight "tick" mark on the primer where the firing pin marked it. Always make sure primers are seated below flush and - yes- I use hard cup primers NOW .

 

[stool]

say what you want ,beleive what you want..
go look at the metal involved....
the cam keeps the firing pin back until the lugs engage....
its a mechanical design..not an opinon.

the dimple is all the pin can do..it has not enough mass to do more in the short distance it can move on its own..

 

[BigDMT]

Well then what about CCI 450s or Rem 7 1/2s? Is there troubles with slam fires using them or is it just Federal mostly? I know the 450s and 7 1/2s are designed with harder cups than their 400 and 6 1/2 counterparts respectively.

 

[afrench]

Well then what about CCI 450s or Rem 7 1/2s? Is there troubles with slam fires using them or is it just Federal mostly? I know the 450s and 7 1/2s are designed with harder cups than their 400 and 6 1/2 counterparts respectively.

i only had trouble with the fed 210 and suspect the 205 could give similar results. the 450 is cci's mag primer and should be fine. never tried any of the 7 1/2s, so can't give input there.

 

[afrench]

say what you want ,beleive what you want..

will do.

 

[BigDMT]

I haven't reloaded for my 5.56 ARs yet because I got a really good deal on a bunch of match grade factory ammo, but this thread concerns me because I have been loading my 6.8 SPC with GM210M primers. Though I have only loaded single shot in the magazine for load development, I did find an accurate load and loaded up 50 rounds to run through my 2 Barrett magazines at full capacity for a function test.

I guess I'll just have to be careful and see what happens...

 

[SS427]

Start your own thread if you want an AR slam fire pissing match. I just want to know if these two primers are the same.

 

[BoydAllen]

http://68forums.com/forums/showthread.php?32572-Here-s-the-skinny-on-the-Federal-GM205MAR-primer

 

[chapstix97]

I bought 5 k from wideners when no other primers had been available. I used 2k to date,
they seen a little harder to seat then the fed standard match especially if I was using swaged lake city brass. The standard match, winchester primers seated easier. I like the standard fed match. I wouldn't spend the extra $ because so called slam fire. Never had one in 30 yrs. I just bought them they were the only ones available

 

[BigDMT]

Start your own thread if you want an AR slam fire pissing match. I just want to know if these two primers are the same.

You already got your answer in the first post. Now we are moving on with more info and opinions. Threads evolve and that's how people learn new and unexpected information.

I knew about "cook offs" from the military and slam fires in bolt rifles due to trigger issues, but I have never heard about a slam fire in an AR before this thread. It's nice to know the possibility is there. By keeping that thought in the back of my mind when operating one of my AR's I am now much more likely to handle a slam fire safely.

I hope I never have a slam fire, but someone trying to inform folks of a possible safety issue should NEVER be ignored or discredited. So thank you all for the info

 

[Minesweeper3433]

My unit had several issues over seas with soldiers coming in for maintenance on their rifles complaining of slam fires. Every single time it was someone who got it in their head to dink around with their trigger or replace it all together. I am honestly still not sold on the issue. As far as primers go I take what I can get at reasonable price which at the moment is those tulamo primers. ATF did do a test once on someone's gun who had installed an automatic trigger and selector. The gun would go full auto with 223 ammo that had soft enough primers. But when tested with winchester ammo it didn't shoot full auto the hammer just followed the bolt forward and came to rest on the firing pin in a more gradual manner. This is the closest thing I have found in documented form that came to "slam firing". The hammer was just following the bolt forward however so this doesn't quite count in my book.

 

[akajun]

The only time I have ever seen a slam fire in an ar or ar 10 is from single loading without a magazine by letting the bolt close from all the way back. Evidently the mag slows down the bolt enough to prevent that.
The real issue with .223/556 or military type primers is to prevent pierced primers. The only primers I have pierced are Winchester sr, and then I think it had more to do with my load than the primer. Still since switching to wolf sr or cci mag, I have not pierced a primer yet, but have blown out a primer pocket or two with some 600 yd experimentation loads .

 

[SS427]

You already got your answer in the first post. ....

You need to read that again. I got a theory at best and even that post confesses he doesn't really know.

As usual, Boyd's post was helpful. Up until then it was turning into a typical pissing match that often seems to develop on this forum these days. While Boyd's link was helpful, I put a lot more trust in most the members of this forum and was hoping someone would really know.

I will try and contact Federal and find out. Will post response here if I find out anything useful.

 

[searcher]

I would say the A/R match primers are not the same as the regular small rifle primer. Most folks on this thread have referenced a harder cup as being associated with the A/R primer but I was told by a wholesaler that a priming mixture that is not as sensitive is more likely the change (he too was not positive). I do know that looking at the primer, there are at least two visible differences - one the imprint on the outside of the cup indicating A/R, and the other the color of the priming compound - which is different. I surely doubt ATK would go to all the trouble of running seperate cups (or imprinting the same ones) and changing the color of the priming compound for no reason. I do know they work exceptionally well in the several A/R's I shoot them in (.223, .556, 6.5 Grendel, .20 Practical) I get consistent velocities and not a dud in over 4,000 so far. As an ex-Marine who spent some time as an armorer, I can attest it is surely not easy to get a slamfire out of an A/R (or at least an M-16), then again the military does not use ammo with high primers, nor chambers not checked for headspace, sensitive primers, etc. I would think the greatest chance would be single loading a high-primered round.