Federal GMM issues in a semi auto 308?

Fenix Mike

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I have two Sig 716 rifles that I shoot, one setup for distance with a NF and one with a red dot. Anyway ive been shooting a steady diet of Hornady Amax 168 through the one for long range, and mostly CBC or similar 147 gr stuff out of the red dot. Last week I brought a few different kinds of ammo out to see what grouped better in the long range setup - Federal GMM 168 gr, GMM 175 gr, and the Hornady Amax 168 it was using. This rifle gets shot to 1000m when I take it out so I wanted to see if it would take the 175s instead since the 168s go subsonic at about 900-950 meters depending on the day. Out of the 3, the Federal GMM 168s grouped best with 1/2 MOA, followed by Hornady at 3/4 MOA and lastly the 175s which would be 3/4-1 inch at best, always seemed to be a flyer opening up the group. Thats the back story, so I went and bought 200 rounds of 168 Federal GMM and decided to stop using the hornady.

Went out today and loaded up a couple mags with the 168s and about 1 in every 10 rounds blew the primer out, and almost all of them had some pretty severe ejection marks on them. I also noticed when I zero'd that I had to come down a decent amount from where the 168 Amax rounds were to get on center. They grouped just fine with most groups being 1/2 to 3/4 MOA, and it did fine at 700, 800 and 1000m even with a decent wind. Just to see if it was the gun, I took my other sig, loaded up a mag and got the exact same issue with about 2-3 rounds out of every mag blowing out the primers.

Prior to this, the scoped gun had about 200 or so rounds of Hornady Amax, other than the two boxes I used last week to see which grouped better, if there was a popped primer last week, I didnt notice it. I still have to go through the brass to see if there were any ejector marks like these, but im also told the Federal brass is very soft and tends to get marks like that on semi auto guns. I have been shooting the 168 and 175 gr GMM in my savage bolt gun with no issues, and have a new remington 700p to try out this weekend to see if it has similar issues or not. I might call federal with the LOT number to see if there are any issues with the 200 rounds I got and I have a couple boxes from a separate lot to try out in the Sigs to see if they have similar issues.

Anyone have any ideas? I have plenty of Hornady if I should just go back to that but the GMM seems to do better on paper and at long range
 

FailureToStart

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I've been told the opposite - Federal brass is hard and Hornady is soft. My OBR leaves ejector swipes in all of its victims... er, spent casings - enough so that between the ejector gouge and the light spiral flute imprint on the side I can pick my brass out of a pile. The swipes in the Hornady brass are more like gouges with nearly 1mm of material sticking up in some cases. All of the Federal stuff I've shot comes out better, usually with just a 'polish' rather than a gouge. I can sometimes catch a fingernail on the end of it but not always.

It could be something as stupid as bullet setback from hitting the feed ramps causing a slight variation in pressure. You might try hand loading a few rounds into the chamber and seeing if you have any drastic changes in the condition of the spent casings or POI.

If all else fails I'd call Federal and ask them whats up. I just hope you don't get some righteous goober who rants about the need for crimped bullets and primers in semi-auto weapons.
 
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fdkay

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    I suggest you try a few boxes of American Eagle 168OTM, it is loaded with the speer 168, tends to be very accurate and is made for semi-auto match rifles (crimped primers)
     

    Fenix Mike

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    I suggest you try a few boxes of American Eagle 168OTM, it is loaded with the speer 168, tends to be very accurate and is made for semi-auto match rifles (crimped primers)

    I dont think ive seen anything with the words "308" or "7.62x51" on the shelves for a while, but I will keep my eyes open! I see cases in bulk online once in a while and usually snag them if they are decent and thats how I got the Hornady and GMM, but I havent seen much else other than Prvi match. I do have a box of black hills 168 that I think I got on trade a while back, I will give that stuff a try.
    I wish primers, powder and bullets would just become available again so I can start loading these on my own... Then I have to hope this brass isnt destroyed :(
     

    powereng

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    I just went through this same issue with blown/cratered primers and my GAP-10. I sent a 100 rounds of the same lot of FGMM back to Federal this past February. They tested all the ammo and it tested good with an average pressure in the 56,000 psi range. They even replace all the ammo I had sent them with new stuff. I shot this same lot of ammo in my Noveske N6 and never had a problem. My buddy shoots all FGMM in this OBR and has never had a problem. I wont go into details here, but I have since sold the rifle. What I can tell you is to contact ATK/Federal Premium, follow the prompt to their customer technical support and ask for Ryan. They will do their best to help you.
     

    Fenix Mike

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    I just went through this same issue with blown/cratered primers and my GAP-10. I sent a 100 rounds of the same lot of FGMM back to Federal this past February. They tested all the ammo and it tested good with an average pressure in the 56,000 psi range. They even replace all the ammo I had sent them with new stuff. I shot this same lot of ammo in my Noveske N6 and never had a problem. My buddy shoots all FGMM in this OBR and has never had a problem. I wont go into details here, but I have since sold the rifle. What I can tell you is to contact ATK/Federal Premium, follow the prompt to their customer technical support and ask for Ryan. They will do their best to help you.
    Thats what I was afraid of... Both Sigs do it, and both have pretty low round counts so might just be a problem with their chambers. I suppose I should call and ask them as well if they have test fired any specific ammo in their guns. My buddy is going to bring his bushmaster 308 out and test the rounds in those too, I may just switch back to the TAP ammo since I really dont care about groups other than when I zero but I was just impressed how the GMM ran out of that gun.
     

    powereng

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    Thats what I was afraid of... Both Sigs do it, and both have pretty low round counts so might just be a problem with their chambers. I suppose I should call and ask them as well if they have test fired any specific ammo in their guns. My buddy is going to bring his bushmaster 308 out and test the rounds in those too, I may just switch back to the TAP ammo since I really dont care about groups other than when I zero but I was just impressed how the GMM ran out of that gun.

    Yes, FGMM shot excellent in terms of groups in both my GAP-10 and my N6. Not being able to shoot my large surplus of FGMM was one of the contributing factors in selling my GAP.

    Just a word of caution. Keep a close eye on your firing pin. The hot gasses from the blown primers will damage your firing pin over time. Plus the small pieces of primer, pierced by the firing pin, get pulled back into the bolt carrier. Collect enough of them and you and can start to having reliability issues.
     

    Fenix Mike

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    Yes, FGMM shot excellent in terms of groups in both my GAP-10 and my N6. Not being able to shoot my large surplus of FGMM was one of the contributing factors in selling my GAP.

    Just a word of caution. Keep a close eye on your firing pin. The hot gasses from the blown primers will damage your firing pin over time. Plus the small pieces of primer, pierced by the firing pin, get pulled back into the bolt carrier. Collect enough of them and you and can start to having reliability issues.

    I actually sold one of the Sigs to my buddy yesterday after shooting, so I was thinking about looking for a SCAR 17 to replace it. I like the rifle overall too much to get rid of both of them but he wanted the FDE gun bad, and I really dont care what color it is so I figured id buy another black one. It seems to be perfect with every other ammo ive tried so I might just have to avoid the GMM in that gun. Did the GAP shoot everything else ok?
     

    insight3b

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    FGMM is hot ammo. Through my bolt 700 when the ambient temp is above 70 I get cratered firing pin marks on the primers and ejector marks...above 80 degrees and the bolt handle is sticky. I guess thats why recently they started crimping the primers.
     

    Fenix Mike

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    FGMM is hot ammo. Through my bolt 700 when the ambient temp is above 70 I get cratered firing pin marks on the primers and ejector marks...above 80 degrees and the bolt handle is sticky. I guess thats why recently they started crimping the primers.

    im going to have to go look though the brass I fired out of my bolt gun and see how the primer pockets look. I figured it was hot judging by how high it was even over the TAP 168s, but its a pain in the ass stopping and looking for a primer each time it blows one out.
     

    powereng

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    I actually sold one of the Sigs to my buddy yesterday after shooting, so I was thinking about looking for a SCAR 17 to replace it. I like the rifle overall too much to get rid of both of them but he wanted the FDE gun bad, and I really dont care what color it is so I figured id buy another black one. It seems to be perfect with every other ammo ive tried so I might just have to avoid the GMM in that gun. Did the GAP shoot everything else ok?



    Good choice on the SCAR 17. I have a SCAR 16 that I absolutely love.

    The only other ammo I shot thru the GAP was one box or Hornady Super Performance Match and a few reloads. All had problems. I only owned the rifle January thru March of this year, so I couldn't find a lot of other ammo to test during that time. However, in my mind if a rifle can't shoot one of the most popular brands of factory match ammo, it isn't worth owning. Not to say ammo can't be at fault. However, once you remove ammo from the equation, you now have to start dealing with the rifle itself, which can be a royal PITA!
     

    insight3b

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    im going to have to go look though the brass I fired out of my bolt gun and see how the primer pockets look. I figured it was hot judging by how high it was even over the TAP 168s, but its a pain in the ass stopping and looking for a primer each time it blows one out.
    That would suck to try and find a popped primer at the range...theres a pic in the reloading section that shows a cratered firing pin mark on a stout load for reference
     

    pmclaine

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    Hmmm, I just picked up two boxes of FGGM 168 to fire through my LMT MWS.

    I'll watch for issues.
     

    Fenix Mike

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    Hmmm, I just picked up two boxes of FGGM 168 to fire through my LMT MWS.

    I'll watch for issues.

    please let me know how it shoots... unfortunately not many people I know (locally at least) really put these rifles to distance with expensive ammo, most just shoot surplus and plink so I dont have anyone to compare it to.
     

    Fenix Mike

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    Good choice on the SCAR 17. I have a SCAR 16 that I absolutely love.

    The only other ammo I shot thru the GAP was one box or Hornady Super Performance Match and a few reloads. All had problems. I only owned the rifle January thru March of this year, so I couldn't find a lot of other ammo to test during that time. However, in my mind if a rifle can't shoot one of the most popular brands of factory match ammo, it isn't worth owning. Not to say ammo can't be at fault. However, once you remove ammo from the equation, you now have to start dealing with the rifle itself, which can be a royal PITA!

    I hated scars for the space boot butt stock, but my buddy down here has one with the VLTOR kit and standard butt stock and it looks AWESOME! So that pretty much sold me on wanting one after the video game look was gone. Sucks about the triggers too, but I had planned on dropping a trigger in it anyway.
     

    pmclaine

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    please let me know how it shoots... unfortunately not many people I know (locally at least) really put these rifles to distance with expensive ammo, most just shoot surplus and plink so I dont have anyone to compare it to.

    I think FGMM is the .308 standard for precision shooters that dont reload based on everything I have read. I have been using ammo bought through the CMP, Atomic Ammo 168 grn over Varget at +/- 2600 fps. It is remanufactured using mixed NATO brass. It has worked well and shoots about 1.5" for me, it would shoot better for others.

    I bought the FGMM as I expect its homogeniety will shoot better than the reman. Otherwise it is supposed to be the "vanilla ice cream" load that shoots well in every .308. Never heard any pressure issues mentioned with it.
     

    Graham

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    FGMM is hot ammo. Through my bolt 700 when the ambient temp is above 70 I get cratered firing pin marks on the primers and ejector marks...above 80 degrees and the bolt handle is sticky. I guess thats why recently they started crimping the primers.
    Nope. And nope. FGMM is not hot ammo and crimping the primers has nothing to do with it.

    That, and SIG is blowing-off the OP and hoping that he goes away.

    Federal did have a problem with a few lots, though. Maybe give them a call and read them the lot numbers to rule out an ammo issue.
     

    insight3b

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    Nope. And nope. FGMM is not hot ammo and crimping the primers has nothing to do with it.

    That, and SIG is blowing-off the OP and hoping that he goes away.

    Federal did have a problem with a few lots, though. Maybe give them a call and read them the lot numbers to rule out an ammo issue.

    FGMM is hot ammo and has ALWAYS shown pressure signs in my rifles over the past twenty years...I guess that isn't enough experience though.
    If there wasn't a problem with the ammo being hot and blowing primers then why in the fuck would they go through the additional step of crimping the primers? Perhaps it is cheaper and less time consuming to crimp the primers during a production cycle?
    yes and yes?
     
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    Graham

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    FGMM is hot ammo and has ALWAYS shown pressure signs in my rifles over the past twenty years...I guess that isn't enough experience though...
    It's not the amount of experience I take issue with, it's the quality of it. If the load it too hot the solution is to modify the load, not crimp the primer, which is exactly what they did when ammo in Iraq was being subjected to unforseen high temperatures. Regular FGMM does not have crimped primers. 7.62 FGMM is crimped, as is the military stuff. Why? Sinister can correct me if I'm wrong, but I think it's a military contract requirement.
     

    Fenix Mike

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    Nope. And nope. FGMM is not hot ammo and crimping the primers has nothing to do with it.

    That, and SIG is blowing-off the OP and hoping that he goes away.

    Federal did have a problem with a few lots, though. Maybe give them a call and read them the lot numbers to rule out an ammo issue.

    I meant to grab a LOT number this morning before heading to work, I plan on calling them tomorrow just to ask. Worst case I will just use it in my bolt guns or trade it to someone for Hornady or black hills.
     

    Fenix Mike

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    It's not the amount of experience I take issue with, it's the quality of it. If the load it too hot the solution is to modify the load, not crimp the primer, which is exactly what they did when ammo in Iraq was being subjected to unforseen high temperatures. Regular FGMM does not have crimped primers. 7.62 FGMM is crimped, as is the military stuff. Why? Sinister can correct me if I'm wrong, but I think it's a military contract requirement.

    Well I am in AZ, this is one of the first "Hot" weeks of the year so far as it was 85-90 degrees this week, and we were shooting mid afternoon around 2-3 pm. Could that be the difference in pressures since the prior few months it was below 75? I have my ammo next to my rifle in the sun, but didnt know that would cause an issue.
     

    Fenix Mike

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    DavidAR10

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    I will have to look into that more. The Sig rifles have a fully adjustable gas system, and we even shut the gas off a few times to see if operating the bolt by hand would change things and it didnt.

    Brutal ejector swipes AND flattened primers AND primers blown out of their pockets in a DI AR...

    da-da-damn Headspace and Overgassed. With your adj. gas system, get your headspace checked.

    I could have thrown in Cracked Case/Seperation at the Swell, but I won't. {that brings up the problem of gas-cutting, da-da-damn}
    Rifle was shooting 3/8" 5rd groups at 100yds while all of this was going on.
    Richard Clancy was told to build a replacement upper from the ground up. The replacement
    sometimes did 1/4" 5rd @ 100yds groups and fired brass looked as if it came from a
    benchrest bolt stick.
     
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    FLIGHT762

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    Fenix Mike,
    I was blowing primers with some of my hand loads in my AR15 and the Tubbs Carrier Weight System stopped the problem and increased accuracy...might work for you too:
    AR-15 Carrier Weight System - AR 15 PRODUCTS by Superior Shooting Systems

    I also use the CWS with the heavy Tungsten weight in my SR-25. It has helped the galling issues with Federal GMM. My early production (1993) SR-25 has always galled badly with 168 FGMM ammo and beats Federal brass badly. When it was new, it would blow 3-4 primers per box of ammo. I was told by Knight's that the rifle will settle in because of the tight chamber, keep shooting it. It did a little bit, but would occasionally blow a primer. Most of the Once FGMM fired cases had primer pockets that were stretched after firing.

    Some of the first lots of Hornady 168 TAP ammo would blow primers in my SR-25. I worked with Hornady's L/E division regarding this and I was sent new lots of ammo and this ammo shot better without blowing primers. I have just over 2K down the tube. I used this rifle on our tactical team for about 15 years.

    I reload for it now after retiring. I do have to keep the powder charges a little lower by a grain or two from my bolt gun loads in the SR-25.

    Try the Tubbs Carrier Weight System. It's not expensive and it can be used in other AR guns.
     

    Fenix Mike

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    Brutal ejector swipes AND flattened primers AND primers blown out of their pockets in a DI AR...

    da-da-damn Headspace and Overgassed. With your adj. gas system, get your headspace checked.

    I could have thrown in Cracked Case/Seperation at the Swell, but I won't. {that brings up the problem of gas-cutting, da-da-damn}
    Rifle was shooting 3/8" 5rd groups at 100yds while all of this was going on.
    Richard Clancy was told to build a replacement upper from the ground up. The replacement
    sometimes did 1/4" 5rd @ 100yds groups and fired brass looked as if it came from a
    benchrest bolt stick.


    Its a piston gun... and I would have thought assembly or rifle issue if only one did it, but both guns? Unless the guys at Sig were just asleep at the wheel! One of my Sigs is a year old and the other about 2-3 months old so they are different production times too. Id hate to send them both back to Sig for warranty and sit on a shelf only to get the same "Its your ammo, even though everyone in the world uses it" response. My friend I sold one of the Sigs to is going to make up some custom loads for his and test everything out, if he comes up with something I will probably follow whatever he does. I checked the firing pin and it looks clean still, but im going to switch back to Hornady until I figure this out.
     
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    Fenix Mike

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    I also use the CWS with the heavy Tungsten weight in my SR-25. It has helped the galling issues with Federal GMM. My early production (1993) SR-25 has always galled badly with 168 FGMM ammo and beats Federal brass badly. When it was new, it would blow 3-4 primers per box of ammo. I was told by Knight's that the rifle will settle in because of the tight chamber, keep shooting it. It did a little bit, but would occasionally blow a primer. Most of the Once FGMM fired cases had primer pockets that were stretched after firing.

    Some of the first lots of Hornady 168 TAP ammo would blow primers in my SR-25. I worked with Hornady's L/E division regarding this and I was sent new lots of ammo and this ammo shot better without blowing primers. I have just over 2K down the tube. I used this rifle on our tactical team for about 15 years.

    I reload for it now after retiring. I do have to keep the powder charges a little lower by a grain or two from my bolt gun loads in the SR-25.

    Try the Tubbs Carrier Weight System. It's not expensive and it can be used in other AR guns.

    I guess for $50 I can try it, but im going to inspect the primer pockets from all my other brass, and try a couple boxes of other GMM I have from a different lot. I found 2 boxes of 168 and 4 of 175 that I was using in my Savage from a different LOT. The Sig has 4 gas settings - Off, under, normal and over, and it wasnt helping with the issue, but if this Tubbs CWS will help out anyway, it might be something to look into. It just bothers me how consistent this gun was with Hornady, and the other with anything 147 grain I fed it, then to go nuts with GMM.
     

    mavrick10_2000

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    I actually sold one of the Sigs to my buddy yesterday after shooting, so I was thinking about looking for a SCAR 17 to replace it. I like the rifle overall too much to get rid of both of them but he wanted the FDE gun bad, and I really dont care what color it is so I figured id buy another black one. It seems to be perfect with every other ammo ive tried so I might just have to avoid the GMM in that gun. Did the GAP shoot everything else ok?

    Just remember with the SCAR FDE is a thought more than reality. The most recent batch uppers are OD green, the lower is more of a burnt bronze Cerakote color, the pistol grip is a shade or two darker than Magpul FDE and the stock is pretty close to Magpul FDE, so no one part color matches the other. Something to keep in mind if that sort of thing bothers you.
     

    FLIGHT762

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    Federal brass is soft. I'm lucky to get anymore than 2 loadings out of it in My SR-25 when loading to normal 168 velocities (2650 FPS). Forget loading anything faster in the 168 weight. Call Tubbs and ask them if their CWS will work on a piston gas system. Remington, Hornady and Winchester brass galls much less than Federal.
     

    GONIF

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    About 4 or 5 years ago I had a problem with FGMM 168 that I bought from CDNN for $18.99 a box of 20 in a case lot in a very early production PTR i have .The head space was dead on and only the FGMM was a problem with blown out primers. I just stopped shooting it in the PTR and used it in my 5R bolt gun untill that batch was all gone . I also have a SIG 716p and it will digest ANY ammo I feed it ( includeinf FGMM,though not the same batch ) with no problem . I never did find out why that batch of FGMM was a problem in the PTR. My PTR is #xx48 and has the original match barrel with the so called tight chamber ,that has not been a problem with with any other ammo I have shot includeing match or surp ammo of every kind of brass cased except that 1 batch of FGMM ammo . So you can take that for what it's worth .
     

    Fenix Mike

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    About 4 or 5 years ago I had a problem with FGMM 168 that I bought from CDNN for $18.99 a box of 20 in a case lot in a very early production PTR i have .The head space was dead on and only the FGMM was a problem with blown out primers. I just stopped shooting it in the PTR and used it in my 5R bolt gun untill that batch was all gone . I also have a SIG 716p and it will digest ANY ammo I feed it ( includeinf FGMM,though not the same batch ) with no problem . I never did find out why that batch of FGMM was a problem in the PTR. My PTR is #xx48 and has the original match barrel with the so called tight chamber ,that has not been a problem with with any other ammo I have shot includeing match or surp ammo of every kind of brass cased except that 1 batch of FGMM ammo . So you can take that for what it's worth .

    I ended up just selling it all this morning. Found Hornady super match at one of my suppliers so might order a bunch of that and try it.
     

    FLIGHT762

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    I don't know if the super Match you're looking to buy is the Superformance Match ammo. I've read on the net that the Superformance match stuff is not good in a gas gun due to the powder being slower burning than a gas gun likes. I've not tried it myself.
     

    Fenix Mike

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    I don't know if the super Match you're looking to buy is the Superformance Match ammo. I've read on the net that the Superformance match stuff is not good in a gas gun due to the powder being slower burning than a gas gun likes. I've not tried it myself.

    Hmm I have one box at home I will have to try first. The gun LOVES TAP 168 Amax but its getting harder and harder to find lately. I had a gift card to Bass Pro and it was the only 308 ammo they had at $38 a box so I snagged that and two bags of jerkey, almost forgot I had it!
     

    GhostFace

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    Mike get the Mornady match #8105 and stay away from that Superformance in a semi. the pressure curve seem to be giving a bunch of guys fits in their semis. Not all but enough guys have had problem, so much so that I wouldn't put it through my rifle. The #8105 is standard pressure 178 BTHP, it runs 2568 through my 18 inch AR-10T.
     

    cb4017

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    I've shot FGMM through several Armalite AR-10s, a Colt LE901, a S&W M&P-10 and a SCAR-17 with no problems. Works good in my issue 700P and personal 700 SPS Tactical too.
     

    BLDTYLRY

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    The Sig 716 is a 7.62x51 chamber and could running higher pressure 308win ammo cause these issues?
     

    EZTundra77

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    It's not the amount of experience I take issue with, it's the quality of it. If the load it too hot the solution is to modify the load, not crimp the primer, which is exactly what they did when ammo in Iraq was being subjected to unforseen high temperatures. Regular FGMM does not have crimped primers. 7.62 FGMM is crimped, as is the military stuff. Why? Sinister can correct me if I'm wrong, but I think it's a military contract requirement.

    FGMM 7.62 NATO does use a different case than FGMM .308. The primers are staked in the NATO rounds, not so in the .308 to my knowledge. The brass is dull in the NATO FGMM. It's polished in the .308. Federal claims on their website that the 2 rounds are loaded to create the same pressure, even though the case thicknesses differ. I find that hard to believe. The boxes even show varying ballistics between the 2 rounds. I can't confirm or deny that they're loaded hot. My Saiga .308 eats 'em both up, as does my R700SS r5 milspec.
     

    EZTundra77

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    Jul 2, 2012
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    Assuming there is higher pressure in that particular .308...that's possible but unlikely. You would usually see that type of problem in older rifles designed for 7.62 x 51. However, the neck placement and angle are slightly different between the 2, so if your tolerence is very tight on a gun designed for NATO rounds, .308's could have issues fitting properly. I believe I've heard that some M-60's don't like .308 loads. I wish i could confirm that 1st hand. If only I had an M60, I wouldn't have to worry about which college to send my girls to.
     

    Fenix Mike

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    Aug 19, 2012
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    Yeah, but was it FGMM .308 or FGMM 7.62 x 51. Federal says they're the same, but they're not.

    Mine was 308, I sold it to two guys with bolt guns and told them about the issue I had... With ammo being this hard to find they didnt seem to care. I wish there was more available at a decent price, id love to find the NATO stuff with the staked primers and give it a run. I havent found a more accurate round yet out of this gun, but I dont want to chance damaging it with the primers going into my rifle or destroying the firing pin.
     

    Fenix Mike

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    Mike get the Mornady match #8105 and stay away from that Superformance in a semi. the pressure curve seem to be giving a bunch of guys fits in their semis. Not all but enough guys have had problem, so much so that I wouldn't put it through my rifle. The #8105 is standard pressure 178 BTHP, it runs 2568 through my 18 inch AR-10T.

    I will keep my eyes open! My Hornady distributor only has the super match 168 in stock right now so I will wait until I find some of that stuff.
     

    pmclaine

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    I took a look at the brass from the CMP sourced Atomic Ammo, Nosler CC 168's over Varget at 2600 fps +/-. The brass looked great no ejector marks or signs of pressure on the primers. My LMT has 150 plus rounds through it so it is still fresh. The chamber is cut as a 7.62x51.

    When I picked up the 168 FGMM I also bought a box of the Hornady Zombie Max (168 AMAX) .308. I'll try to shoot some of these Saturday as this thread has me curious what is going on. I'll post what I find.
     

    pmclaine

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    Sorry it took awhile to try the FGMM and Zombie Max ammo in my MWS to determine if there were issues like you are having.

    I just fired 3 10 round groups.



    The top right was Atomic Ammo reman .308 using Nosler CC 168 and Varget. The top right was the Hornady Z Max which I think loads a 168 Amax and comes in a stupid box with the stupid green tip, the center target was FGMM 168. The FGMM gave noticeably more recoil. I do have Slash's heavy buffer in my rifle and could tell the FGMM pushed more, not crazy like my 30-06 1903's but just a bit stiffer than the soft push of the Atomic and Z Max ammo.

    The brass showed nothing spectacular



    I'm pretty impressed with the Atomic Ammo. I hope the CMP can get more. It wasnt a bad price, it shoots just fine, its good brass and there is no better service. There are ten in there somewhere. I knew I threw the bolt lock back shot but I didnt have one completely leave the paper. Somewhere in that knot there is a round on top of a round. I think FGMM can do better, I dont know what I was doing to walk that line.
     
    Last edited:

    Fenix Mike

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    Sorry it took awhile to try the FGMM and Zombie Max ammo in my MWS to determine if there were issues like you are having.

    I just fired 3 10 round groups.



    The top right was Atomic Ammo reman .308 using Nosler CC 168 and Varget. The top right was the Hornady Z Max which I think loads a 168 Amax and comes in a stupid box with the stupid green tip, the center target was FGMM 168. The FGMM gave noticeably more recoil. I do have Slash's heavy buffer in my rifle and could tell the FGMM pushed more, not crazy like my 30-06 1903's but just a bit stiffer than the soft push of the Atomic and Z Max ammo.

    The brass showed nothing spectacular



    I'm pretty impressed with the Atomic Ammo. I hope the CMP can get more. It wasnt a bad price, it shoots just fine, its good brass and there is no better service. There are ten in there somewhere. I knew I threw the bolt lock back shot but I didnt have one completely leave the paper. Somewhere in that knot there is a round on top of a round. I think FGMM can do better, I dont know what I was doing to walk that line.

    The Amax worked great in my gun too, it was just the GMM that had the problem so far. I have a box of black hills im going to try too, just got too busy last weekend. If I get time I Will snap a few pics of the brass from the GMM.