Federal small rifle AR primers

[RJBain]

I was at the local shop this past weekend looking for some primers for my 6 and 22 BRs. I have been using Federal 205M small rifle match primers and I am getting low on them. The only 205m's they have in stock are Federal Premium AR small rifle match primers (part number GM205MAR). I looked on Fereral's web site and they show them as a new product, but do not give much info on them. I am thinking they have a thicker cup to prevent slam fires in the AR, but I do not know for sure. Do any of you folks have any experiance with these? Do the preform like the 205M's?

Thanks in advance,Bob

 

[Curt L.]

bump would love to hear on this as well

 

[mgdietrich]

They have a harder cup than normal 205/205m. Designed for AR's so a light hit when the bolt goes forward doesn't cause detonation.

Compound is the same, so if you like Fed primers no reason these would not be a good fit as well.

 

[Garrison smith]

I have had experience with both 205m and the 205 ar match. In my experience they seem slightly harder to prime than the non ar fed primers. Just a heads up

 

[762plinker]

i tried them, did not like the results, maybe for ftr guys, not for me

 

[markm87]

These have run GREAT for me in small rifle primer 6.5cm Lapua brass. I've had a thousand in the cabinet for some time and gave them a try.

I did a head to head in .223 against WOLF SRMs (which are mild), and the Fed AR match goosed the velocity 40 fps all things equal.

I'd love to get a few thousand more if I find them.

 

[RegionRat]

Agree they are not identical to 205M and you will want to treat them like any other primer, meaning a different one.

I got a stack when they first came out but have not needed to break into them yet. The sample I tested did fine in relation to other small rifle primers including CCI 450 and CCI 41, and REM 7 1/2, with RE-15, Varget and H4350. Pretty soon, I will test them with ball powder in cold weather to see how they do.

I tested in a custom Pierce action in 6 Dasher, and a WOA Service Rifle Upper in 5.56 where the lower has a Geiselle service rifle trigger. These actions all have a very reliable ignition. I have other rifles (Factory Savage) that did not and I had to rework the firing pins and springs to make sure they work with all primers.

I just took a quick look, not an in depth sample. I intended to screen these for weight distribution but have not had the need to just yet. If these were all I could find in quantity, I would take them.

 

[dryhumor]

I have a few thousand of them. One thing I’ve noticed is that the amount of compound in the cup is not consistent. I visually inspect them for consistency before using them, and I use them in several rifles. A few times I haven’t done that and have experienced fail to fires. Likely light primer strikes on less filled cups. Other than that they are pretty consistent.

I just tipped these out. To my eye, the ones on the left appear to have less compound to a degree. These will fire in a couple of my rifles, in a couple more they might not ignite.

 

[Ray123]

The SR brass cups are thicker on AR primers .025" same thickness as BR4, CCI 450, CCI 41, Remington 7 1/2...Mil spec... And magnum or higher pressure loads use the thicker cups, as well as the floating firing pin AR...most of the rest of the SR primer cups are .022" ... there are information "charts" comparing most primer cup thicknesses, & amount of "flash generally produced" ...which reloaders call "hot" or "cool" primers from these primer manufacturers.

 

[Stugots]

This Pix has no information on the Fed 205MAR primers but I thought it might be of some interest to a few.

 

[Benchrest Braxton]

I have a few thousand of them. One thing I’ve noticed is that the amount of compound in the cup is not consistent. I visually inspect them for consistency before using them, and I use them in several rifles. A few times I haven’t done that and have experienced fail to fires. Likely light primer strikes on less filled cups. Other than that they are pretty consistent.

I just tipped these out. To my eye, the ones on the left appear to have less compound to a degree. These will fire in a couple of my rifles, in a couple more they might not ignite.

View attachment 1401851

do 10 of the weird ones then 10 normal. measure groups and velocities on both. might save you alot of time sorting if there is no difference

 

[fkimble@charter.net]

Hard to tell about the compound actually in the primers from the pic, but the green coloring is more prominent on the right side group!

Frank

 

[jepp2]

but the green coloring is more prominent on the right side group!

I think the compound is just under the anvil. The green is just something on the anvil, not the compound.

 

[divingin]

I saw no difference between the Federal AR Match primers and standard CCI's. Both ignite fine from my Bat B, and my R700. Didn't see any noticeable difference on the target.

 

[dryhumor]

do 10 of the weird ones then 10 normal. measure groups and velocities on both. might save you alot of time sorting if there is no difference

That sounds like work…. I just do a quick separation as pictured in the tray. Use the ones as seen on the right when I want consistency and the ones on the left for plinking. It works well.

I am curious though what other peoples Federal AR primers look like. Those of you that have them are they like the ones I pictured or are they all the same?

 

[divingin]

I have a few thousand of them. One thing I’ve noticed is that the amount of compound in the cup is not consistent.

Took a look at mine; the green (I assume that's what you're talking about) appears to be paint on the inside arch of the anvil. The primer compound itself is, like most primers, hidden beneath the anvil and a layer of paper.

 

[Jeff Porter]

I have used several thousand 205MAR and find them very consistent and reliable. No difference in my 223 77gr loads from Wolf magnum Rem 7 1-2 or CCI 450.

 

[DR_2297]

The FGGMAR is also shorter. I believe the anvil is also set further in to help avoid slam fires.

 

[dryhumor]

do 10 of the weird ones then 10 normal. measure groups and velocities on both. might save you alot of time sorting if there is no difference

Even though that sounds a bit like work, and might generate more depending on results, I might go o ahead and do that this spring.

Didn’t intend to push the thread off on a side road. …

 

[divingin]

Took a look at mine; the green (I assume that's what you're talking about) appears to be paint on the inside arch of the anvil. The primer compound itself is, like most primers, hidden beneath the anvil and a layer of paper.

Some pics: