Problem with 5.56 reloads

[the45er]

Well, four days before I leave for north Texas I've got a serious issue with my 5.56 reloads. Probably something simple, but driving me crazy.

I now have 3 5.56 AR-15's. I've been rocking along for months now without a hitch. 25.3 grains of H335 over a 55 grain Hornady V-Max. VERY accurate in all guns. I've reloaded these in "batches" which has complicated my issue.

All of a sudden I started having FTF's in my favorite AR. I'd pull the trigger - the hammer would drop - but no BANG. The round would stick badly in the chamber. I'd get it out and there would not be an indentation on the primer.

First thing I did was take apart the BCG and make sure it was clean, lubed and the firing pin was OK. All good. I fired a few rounds ok and thought all was well. NOT. Tonight I load up a mag and take it out one last time to make sure it was ok. FTF - FTF. Frustrated, I brought out my Stag Arms Varminter which I've fired a bunch of these reloads through - FTF - same symptoms. Live round stuck in chamber.

In short, it's not the guns. I have done something different (and probably stupid) in the last few batches of reloads and I don't know what it is! What's weird is that even the rounds that stuck in two AR's will drop without a hitch into my .223 Thompson Contender barrel!

Measuring them doesn't reveal any differences that I can see. OAL's the same as the ones that fire yadayadayada.

Any suggestions of what I might check or do differently?

 

[243winxb]

{Edit to remove link to copyrighted material. Sorry, but this isn't a workaround for the board policy on posting copyrighted materials because linking through us makes us accessories to the copyright violation.}

To much crimp may bulge the shoulder.

I'd get it out and there would not be an indentation on the primer.

The action was not closed and locked.

 

[Unclenick]

25/3 is Hodgdon's maximum. For reasons having to do with process (working up in productions guns rather than pressure guns) and trying to get multiple bullets to reach the same velocity with the same load, I've found Hornady's data tends to range from about -1% to -9% less than Hodgdon's. This is not to say they are always wrong—these are their bullets they are testing and they could be harder or longer (more deeply seated) than the next guy's—but the overall pattern is pretty clear, so I look at them as extra safe.

In order for the unfired case to be stuck in the chamber, either it isn't properly resized or you adjusted your seater the wrong way and the bullets are jamming into the throat, which will raise pressure, or, as 243winXb suggests, over-crimping has bulged the case at the shoulder. You have no primer indentation because the bolt isn't closing fully on the case, so the firing pin is blocks, which prevents most slamfires. It isn't closing because the case is sticking out of the chamber too far, either due to under resizing, over-crimping, or to the bullet sticking out too far.

Running the loaded rounds through a case gauge will tell if the cases are too long. Checking COL should tell if that's longer than you intended, though it won't necessarily tell you if it's too wide. Painting a round with Magic Marker and chambering and sticking it and then knocking it out backward with a cleaning rod will reveal what surface the cartridge is stopping against and what you need to correct.

If you don't own a cartridge gauge or a comparator, you can improvise with a spacer and a caliper as shown for a .308 Winchester, below. Just pick a spacer whose hole stops in the middle of the shoulder and another that stops on the bullet ogive near the front end of the bearing surface. Use these measurements to compare what you have to commercial ammo. Use the caliper to compare the OD of your case to a new one wherever the Magic Marker is scuffed off.

 

[JeepHammer]

Do you own a head space gauge?

The biggest issue I see with your complaint is shoulder expansion when using a taper/roll crimp.
Seater/crimper in the same die (normal die sets) MUST have EXACT length trimming, no variance at all in length.

Longer brass will crimp harder, screwing up consistency, and sometimes flaring the shoulder bend.

Flared shoulders stick in the chamber really good!
I feel your pain...

Flared shoulders will keep the bolt from reaching full battery, and a properly assembled & fitted bolt/bolt carrier assembly will not allow the firing pin to strike the primer.

You CAN use the wrong shell holder in a single stage press, set your dies up on one shell holder, later use a different shell holder and screw up the crimp.
Not all shell holders are created equal.

A drop in case head space gauge is your 'Last Word' check, drop loaded rounds into the gauge and it will tell you right away if anything went wrong before you find the issue stuck in the chamber...

 

[JeepHammer]

A work around to trimming every single case is a collet type crimper,
Also called a Factory Crimp Die.
Seat bullet & crimp in two steps instead of one.

For range ammo, I usually run brass through the trimmer, most fired brass will be short anyway, cut them to minimum since neck length, minus 0.010" from SAAMI doesn't effect accuracy, and with a 'Factory Crimp' die I don't have to screw with it again.

 

[the45er]

Forgot to mention

I have a 5.56 case gauge and every one of the shells that stuck in the chamber and had to be forcefully removed fall easily into the gauge. Go figure that one!

I have been trimming these cases every time prior to loading. Could I not be chamfering them well enough?

I set the die to give a tiny roll crimp and ran seven of the cases that stuck in the chamber through them. Six fired without a hitch and the seventh one experience a crushed case. I was surprised since I do trim after polishing and depriming.

 

[the45er]

Load data

55 GR. SPR SP

The Hodgdon Reloading site states that the max load for this bullet description is 25.3 grains. Isn't the Hornady 55 grain V-Max pretty much this bullet?

 

[JeepHammer]

If the rounds fit into a case gauge, then look at the bullets once removed, see if they show signs of being jammed into the rifling.

Outside of bench rifle chambers where you have to turn necks thinner, I've never heard of a chamber throat tight enough that a bad champfer would jam.

 

[JeepHammer]

For a case to be trimmed to the MAXIMUM length, it has to be sized first.
Trimming before sizing, when sized, case walls pushed back in, the case gets longer.
I found that one out the hard way about 35 years ago.

 

[Mobuck]

Your cases aren't being fully (or adequately) sized. I have a fairly big "batch" of reloaded ammo that does exactly the same thing in my primary EDC AR. ARRGGG!!!! The cause was a worn sizing die and the result is a batch of ammo that I can't use in that carbine.
The bolt isn't fully closed and the hammer falls but the FP doesn't reach the primer--A VERY GOOD THING IT DOESN'T.

 

[MarkGlazer]

Checklist:
Case fits your case gage
Case length is within spec
Primer seats properly
Powder load meets data requirements (not really a factor)

If all of the above are satisfactory you only have one thing left to do, load a few test rounds and DO NOT crimp. I know there are arguments for both but this is your last variable. Change your process and see what results. I never crimp and have never had a misfired round in my own AR.

PS - have you test fired a factory round? Any issues there?

Good luck

 

[the45er]

As usual, I'm pretty sure the screw up was me!

I now believe carelessness caused the problems with chambering the rounds in my AR's. Instead of setting the resizing die where it would cam over and fully resize, I set it where it barely bottomed out on the shell holder, thereby not allowing a full resize. Because I'd mixed these poorly reloaded shells in with good ones, I had to take 120 rounds and put them in the resizer die with the decapping pin removed. By barely running them up into the sizer a short distance (by feel), I was able to get the shells were they could fully chamber without sticking. Whew! You can bet I'll be more careful in the future.

Regarding 25.3 grains of H335 being too hot, I went on the internet and found several loads that included this amount. In fact, the 8 LB keg of H335 I have has written on the front label 25.3 grains for a 55 grain bullet!

 

[Metal god]

I now believe carelessness caused the problems with chambering the rounds in my AR's. Instead of setting the resizing die where it would cam over and fully resize, I set it where it barely bottomed out on the shell holder,

Depending on the press if you don't have solid contact with cam over . You can have varying case head space from case to case . This is do to press deflection . Some presses are worse then others with this issue . Here is a Hornady single stage press with the die set as you explained above .

First pick shows the ram fully up with no case in the die . As you can see the die and shell holder are making contact with cam over . How ever they are just barely touching .

This pic shows the press set up the same but this time when sizing a case . Notice the gap that is now present between the die and shell holder . That is do to the deflection/stretch/flex of the press and linkage . Now depending on the case and how work hardened it may be . The harder it is to size a case . the more deflection you will get .

I personally use the Redding competition shell holders . They allow you to have hard contact between the die and shell holder while being able to custom size your cases in .002" increments . I love them and would not size a case with out them .

 

[Xdm nut]

I definitely think it's something with your sizing die. I had the same problem with my AR but the rounds functioned with my wife's AR. What I did was take a sized but unloaded case and inserted it into the chamber then let the bcg close. I found even the empty case was sticking. I has to reset my die until the bcg would close and eject the case.

Jeremy

 

[mcintosh]

I have been having the same problem. I've been loading 55fmj in bulk for competition, and had a case stick in the chamber, just out of battery, so that the hammer would fall, but not contact the firing pin. I had to mortar the round out/smack the forward assist with a rock to get the gun open.

What I've found is that my sizing die was not screwed down far enough, leaving my case neck ever so slightly flared out after sizing. Deburring was not enough to remove it, and factory crimp couldn't sufficiently crush it down. The only way to fix it was to re-set the sizing die so that it fully resized the case mouth.

 

[CTSixshot]

Your case diameter should be < .354" at the shoulder. Usually the micrometer, set at .354", will run about 1/4" beyond the shoulder area on a properly sized case..

 

[Reloadron]

Forgot to mention
I have a 5.56 case gauge and every one of the shells that stuck in the chamber and had to be forcefully removed fall easily into the gauge. Go figure that one!

I have been trimming these cases every time prior to loading. Could I not be chamfering them well enough?

I set the die to give a tiny roll crimp and ran seven of the cases that stuck in the chamber through them. Six fired without a hitch and the seventh one experience a crushed case. I was surprised since I do trim after polishing and depriming.

I will take a shot at figuring that one. You have a 5.56 Case Gauge so maybe since your cases passed the gauge you should look at something the gauge doesn't check.

You mention a tiny roll crimp? Personally I just rely on bullet hold or neck tension. Something most case gauges do ot check is the case diameter, both just forward of the case head and right where the case shoulder begins. Case gauges like the L.E. Wilson and similar make it a point to mentiopn:

One piece gage that will check overall length to indicate the need for trimming, datum to head length to assure correct headspace and to prevent over sizing. Available for most popular rimless cases.

Note: Does not measure body diameters. This gage is intended to be used with fired cases to determine a basis for full length sizing and trimming.

What can happen here is if during your bullet seating the seating die is set too low the case at the base of the shoulder becomes slightly enlarged. Measuring a .223 Remington case just as an example it should look like this. You may want to get out your calipers and compare some of the case dimensions in the drawing to your problem cases. Enter the .354 dimension mentioned above.

Sheridan Engineering does have a line of case gauges which are cut using a reamer as was used to cut a chamber including the case diameters. Anyway, since your gauges passed your case gauge I would be looking at dimensions the case gauge doesn't look at.

I believe I also saw mentioned using a black magic marker to blacken a problem case and then try to chamber it. Remove the case and not where the blackening has been rubbed. That would be the problem spot. You have likely loaded plenty of non problematic .223 Remington in the past and all of a sudden there is a problem. Something has changed.

Ron

 

[Xdm nut]

On mine it was the shoulder not being bumped back enough not the case neck. Lowering the die bumped the shoulder back slightly and it worked fine.

 

[CTSixshot]

I can't speak for case gauges other than L.E. Wilson, but Wilson's do not measure case diameters, but shoulder positioning. You can have cases that drop into the headspace gauge just fine and bind while chambering.
Check your case dimensions...



Both check fine in the Wilson gauge, but the red marked case (in this case, I neck-sized it only) will likely bind in an AR chamber. Different guns may have variable chambers, but you must check dimensdions on your sized cases, not just shoulder positioning.


I guess what I'm driving at is that a case may drop into the Wilson gauge as advertised, but it may not be within SAAMI specs.

 

[Reloadron]

CTSixShot, thanks for illustrating that so well. One or two pictures is worth.... The problems often happen after the resizing and during bullet seating.

Ron