Cardinal Armory LW grunt 6.8 mounted on a Armalite lower with DPMS Trigger/hammer/disconnect modified by Bill Springfield for 3 lb pull. (including lighter weight springs that he provides).   Cardinal bolt in a Colt bolt carrier with new firing pin.  Millet DMS-1, C Products Mag and SSA 110 Prohunter.



When loading the new C Products mag from Cardinal Armory the first 5 or 6 rounds will not naturally stay flush with the lips. they tend to point tip up.  The next six seem to load correctly and the reminder load tip down.   The 18 round mag only holds 17 rounds.  Tapped the mag on the primer side and went on with the sight in.  Last three rounds would not load into gun while firing.  Photo shows mag after manually working the action.  It will consistently stop loading at the last third or fourth round.   Lead tips of the bullets seem to get overly deformed by hitting the front of the mag when loading from a full mag.  No evidence of damage to the lips spring or follower.  




I had three duds in the first 12 shots.  Had primer strike but no boom.  Photo show three duds and three fired brass.    I changed to another lower with 4 lb Bill Springfield trigger for the remaining 10 shots with no problems.

Note the original lower with 5.56 upper has been through 300 rounds with the BS trigger with no problems shooting Wolf and commercial reloads.



Checked firing pin. No apparent problems.



DMS-1.  I like it so far.  Instructions say 1/4 inch clicks, turrets say 1/2.  turret is right

The Light weight Grunt is very nice and seemed to function well.

No accuracy reports since I never got past a basic sight in.  With all of the problems it seemed pointless.  

QUESTION :  Are my problems with the mag and the ammo/trigger combo typical?

My general feeling is that the mags are the #1 culprit in this problem that you saw, but they won't likely affect the primer strikes per se.  If the bullet is deformed badly enough to obturate in the chamber that might change the relative headspacing and cause this. Did you try banging on the forward assist?

You should try again with either the TSX or the SMK, which won't deform.  Then you should chunk the CP mags and get PRI's  ( I Know, I know I hate to say that, but I have never, ever seen a problem with the PRI's)

The lighter weight springs could potentially result in light primer strikes, but I have actually seen a few "dud" primers in the SSA loads lately.  Jury still out on this.

As mentioned by Hi-Tech the last three to four rounds in your mag having feeding problems is more than likely related to the spring in your mag, which as taken a set (weaken). The cartridge can not get into position in time for the bolt to pick it up properly, therefore the tip is being jammed into the feed ramps, this is not an uncommon problem.

Here at SSA we never load our mags fully, besides we are not in combat. A big no-no is to load the mag and just let it sit around.

We only use Mil-Spec primers on all our rounds and the hammer spring must be able to handle it. The Mil-Spec primer has a harder base than a commercial primer to avoid taping. Because an AR and M16 has a free floating firing pin in a semi or full auto weapon when you stop firing the firing pin thru inertia can move forward and hit the primer, a commercial primer (soft base) can send the weapon into full auto with your finger off the trigger. Many times you can see this light hit (taping) if you eject a round that has been chambered during firing.

Just last week we had to replace a hammer spring in a lower that started producing light hits during testing, this lower had several thousand rounds thru it of various calibers. You had mentioned that when you went to a different lower the next 10 rounds fired had no issues. From your photo the rounds that fired seems to have a wider and deeper hit then the ones that did not fire. That ones that fired were they thru the second lower?

Early on TC'S were producing light hits (50%) and many owners had to change out the springs to shoot our rounds. we had talked to TC way back and for 1 1/2 years we have not heard on any more light hits.

We preform a Military drop test on the primers when we recieve them and to date none have failed the test.

I hope this helps and if you still having issues please feel free to contact us.

Art-SSA





 

Military primers ARE harder, but are required in a combat weapon.  Light triggers are nice for matches, but may not have enough power to initiate military primers.  As Pat Rogers has remarked numerous times, match triggers have no place on real deal working carbines...

SSA and Ko-Tonics/Cardinal are an excellent combination though.

Yes, I'm a self-proclaimed fan-boi of both.

It may be a dumb question, but is the magazine spring directional and could it be seated the wrong way? I have never seen rounds sit that way in a mag before, and it appears that pressure from the spring in not evenly distributed on the follower....

As for the primer strikes, the unfired rounds appear to have a much lighter strike to them as someone else pointed out.

The mag could be either the spring or the mag body could have spots that are bit tight causing the follower not to run smoothly.  I would normally say the spring as CP other then the magpul followers uses lower in components then PRI.  But given that unusual tilt issue I think it may be more to do with follower binding.  You could take the follower out and lightly sand all the edges jsut enough to slightly radius them.

As for the primer stirkes those are much lighter then any of my fired SSA, Hrdy, and hand load primer strike dents appear.  I use a Timney drop in trigger so if they are lighter then mine you are getting light strikes for sure.  If I recall correct Bills mods tot he trigger it  included cutting the hammer and using reduced springs so if one is a bit weak or the hammer has a tad to little mass it will certainly cause this.  Given the other lower had no issues I think points tot he culprit.  You could always try those light strike ones in the other lower and see if the fire.  Actually thats is what I would have done first.  

I know the frustration of having a first outing be filled mis such mishaps.  I sucks.  But I think if you switch  mags and send back the trigger to B to replace and use the other lower in the mean time you will be much happier with the next outing.  Give us an update to the issue and how the next time goes.  Hope it all goes well.

Thanks for the input guys.  

As far as the light primer strikes in the photo.  I don't know which lower the fired brass came from, but all the fired brass looks the same.  

I would assume that had the duds fired the primer would have flattened against the bolt face causing a larger firing pin dent and filling the gap around the around perimeter of the primer as can be seen on the fired brass in the photo.  

Also, in one of the three duds the bullet is loose enough to push in to contact the powder, and I could almost pull it out by hand.  Possibly a loading problem.   I will try shooting the other two with the 4lb and see what happens.

After thinking about it I remember shooting some Malysian m193 in addition to the wolf and commercial reloads with the 3 lb lower with no problems.  I'm not giving up on it yet.

I compared the mag spring to an old colt 20.  Almost exactly the same spring except the colt was weaker.  I traded springs and it actually seemed to load better with a weaker spring.  Just pisses me off that a brand new mag won't work.  Guess I will get a PRI and go from there.  

It erks me to have a gun I can't depend on.  I grabbed my 556 instead of the new 68 yesterday morning for these little orphans.  Killed their mom two weeks ago.