I've Never Had This Happen Before - What Happened to These Primers?

[markr6754]

I was prepping brass from my last outing, where I also fired my newly completed AR-9. I'm pretty sure that these pieces came from that pistol, as the 9mm handguns we brought have seen multiple outings without any unusual primer markings.

These cases, the FC headstamps, were loaded with 124gr HiTek coated bullets over 4.0gr of Hi-Skor 700-X, at 1.070". That's a bit deeper than I wanted to seat them, but that's the problem I run into with these bullets. Otherwise, they don't fit most of my barrels. I didn't plunk my Rosco barrel in my AR9. These are Winchester WSP primers.

The first picture shows several of these cases against one GFL case, a factory 115 gr Fiocchi round. I shot 50 rounds of new factory 115 gr Fiocchi Range Dynamics, and all of them have "normal" primer strike marks as in the sample shown.

The 3rd photo shows that the 5 FC headstamp cases with pierced primers, as indicated by the light shining through in the last. That's one of the 5 before I decapped it. Obviously, another 50 or so cases did not show anything unusual...or not unusual enough to catch my eye.

I used an Odin Works Enhanced 9mm BCG with a standard carbine spring and an Odin Works adjustable buffer loaded to 5.4oz for 9mm, per their instructions. This was the first time out for this configuration.

I'd appreciate any thoughts on things to look at to ensure that this never happens again.

 

[illinoisburt]

Could be lighting but some of those primer strikes appear to be cratered on both reloads and factory. I wonder if the firing pin hole is oversized in the bolt, or you have a headspace issue. Could also be opening too soon.

 

[denton]

Too much pressure for a thin primer.

At one point, the firing pin strike dimple will iron itself flat. Add a little pressure and it will extrude back into the firing pin hole. Add a tiny bit more and the extrusion will break off at the base, leaving a round hole in the primer and a loose metal particle that may jam up your firearm.

Either back down a grain or switch to primers with thicker cups.

 

[fxvr5]

Your load might be too high. Hodgdon shows most loads with 124/125 bullets with a max of well under 4.0 grains, and your short OAL is only going to increase pressure.

 

[EricBu]

If they are only doing it in your newly built AR9, might be a bit of a head space issue on that gun. I'd prime a couple of pieces of brass and pop them off in your basement, that should tell you if it's a build issue. If the primers look good there, then revisit your load and load data, and try to verify if it is only in that one gun.

 

[243winxb]

3.4 gr 700x is maximum with 125 gr lead, in 9mm. Hodgdon & Speer data.

3.2 grs of 700x worked the action of my Taurus G3C with cast. https://www.thehighroad.org/index.php?media/albums/taurus-g3c-9mm-luger.317/

The carbine may have a straight blow back action. They may require a heavier bolt assemble then my G3C that is delayed blow back?

Your carbine may need more powder then my 3.2 grs?

https://www.thehighroad.org/index.php?threads/ar9-virgin-assembly-ka-boom.844227/



Carbines may fire out of battery.

 

[LiveLife]

AR-9 ... 9mm ... 124 gr HiTek coated bullets over 4.0 gr of Hi-Skor 700-X, at 1.070"

Most coated bullets are sized larger at .356" and work well with lead load data.

Since you are using shorter OAL/COL that seats the bullet deeper (and raising pressure), as other members suggested, try reducing start/max charges and see if you get reliable cycling of bolt. Note that even for FMJ bullet, due to shorter OAL, max charge is 3.6 gr and max charges showing higher are using longer OAL.

• 9mm 125 gr Lead RN 700-X COL 1.130" Start 3.2 gr (920 fps) - Max 3.4 gr (977 fps) - https://reloadingdata.speer.com/downloads/speer/reloading-pdfs/handgun/9mm_Luger_125.pdf

• 9mm 125 gr Lead CN 700-X COL 1.125" Start 2.9 gr (899 fps) - Max 3.4 gr (1,003 fps) - https://www.hodgdonreloading.com/reloading-data-center

• 9mm 125 gr Sierra FMJ 700-X COL 1.090" Start 3.0 gr (845 fps) - Max 3.6 gr (1,007 fps) - https://www.hodgdonreloading.com/reloading-data-center

• 9mm 124 gr Berry's HBRN-TP 700-X COL 1.150" Start 3.7 gr (894 fps) - Max 4.2 gr (1,068 fps) - https://www.hodgdonreloading.com/reloading-data-center

• 9mm 124 gr TMJ RN 700-X COL 1.135" Start 3.9 gr (989 fps) - Max 4.3 gr (1067 fps) - https://reloadingdata.speer.com/downloads/speer/reloading-pdfs/handgun/9mm_Luger__124_rev1.pdf

 

[Slamfire]

Cut your load. I called Winchester in 1999 and asked them about their "new" brass finish primers. Before 1999 the whole product line was silver colored. I thought they told me the coating was zinc. One of the things they did was to make the primers more sensitive to "combat offset firing pin hits." What I found was the new brass finish WSR primers pierced at loads that never bothered the zinc plated WSR.

Winchester thinned out the primer cups on all of their primers, WSP included. Now I am going to tell you, to pierce a small pistol primer, regardless of make, your pressures are way too hot. Cut the load.

Cut the load by a half a grain till the primers stop piercing. Ignore book values, book values are a guide, but each and every barrel and chamber are different. I know this is not what you want to hear. Most reloaders want a magic rabbit's foot waived over their bench to make their problems go away. No amount of hand waiving is going to make high pressures disappear. But cutting your load will.

 

[Akula69]

Most reloaders want a magic rabbit's foot waived over their bench to make their problems go away.

Can I have my foot back now?

 

[Palladan44]

Start at starting published load

 

[longdayjake]

You probably need to put more weight in your buffer. Looks to me like it's got some bad timing and the casing is starting to come back before bullet has left the barrel.

 

[markr6754]

These are some well thought out answers. I appreciate them, including the Magic Rabbit Foot reference. I've found that a Rubber Chicken works better, and doesn't maim any rodents. This is a case of doing everything wrong for all the wrong reasons. I hate these Summit City bullets, so I was just focused on getting rid of them as soon as possible. I hate loading them, and I couldn't get them to fit in my handgun barrels until I seated them well past my comfort level....which is why I decided to shoot them in my new build AR9. Didn't give enough thought to what would happen when a hot load with a fast powder was coupled with a heavier bullet and a too short OAL. Considering what I spent on that build it was rather stupid decision. It would certainly be cheaper to just toss those bullets in the trash.

Considering the photo posted by @243winxb I'll consider myself quite fortunate that all I did was put some pukas in a few perhaps too soft primers.

Regarding the buffer, I just re-checked the weight...it is 7.5oz, the maximum achievable in this buffer. I also removed and checked the firing pin. I was surprised, and delighted to discover that it isn't free floating...it is springed, so the firing pin retracts after being struck.

 

[LiveLife]

124 gr HiTek coated bullets over 4.0 gr of Hi-Skor 700-X, at 1.070"

pierced primers ... to ensure that this never happens again

Didn't give enough thought to what would happen when a hot load with a fast powder was coupled with a heavier bullet and a too short OAL

Referencing more conservative lead and jacketed load data, if shooting test rounds at 3.0, 3.2, 3.4 and 3.6 didn't produce pierced primers, then you could ensure pierced primers never happen again with this particular combination of bullet/powder using mixed range brass - https://www.thehighroad.org/index.p...ppened-to-these-primers.914104/#post-12502787

And that's the thing with mixed range brass, we just don't know how many times they were reloaded and how much work hardening they experienced to expand with remaining malleability or not. Some of the cases experiencing pierced primers and some not could be the result of mixed range brass with different reload history.

I couldn't get them to fit in my handgun barrels until I seated them well past my comfort level....which is why I decided to shoot them in my new build AR9

Had the "plunk test" been done with AR9 barrel to perhaps use longer OAL, could have worked with higher 4.0 gr charge without piercing primers.

There's one way to find out ... Load some rounds longer to max/working OAL for the barrel/magazine and reuse the brass that produced pierced primers. (And I would also test 3.8 and 3.6 gr charges at longer OAL)

If no pierced primers with same headstamp brass at longer OAL and/or lower powder charges, then the rounds were overcharged.

You probably need to put more weight in your buffer. Looks to me like it's got some bad timing and the casing is starting to come back before bullet has left the barrel.

That was my initial thought as well and was going to ask OP what the combined bolt/buffer weight was until I read buffer weight of 5.4 oz was being used (H3 buffer weight) and should bring the combined weight to around 20 oz and fall within ideal 20-22 oz for less harsh recoil and increased bolt contact dwell time with chamber - https://www.thehighroad.org/index.p...troke-bolt-for-9mm-pccs.913393/#post-12484268

Odin Works Enhanced 9mm BCG with a standard carbine spring and an Odin Works adjustable buffer loaded to 5.4 oz for 9mm, per their instructions. This was the first time out for this configuration.

Then OP posted

Odin Works adjustable buffer ... I just re-checked the weight...it is 7.5 oz, the maximum achievable in this buffer

So heavier 7.5 oz buffer should bring the combined bolt/buffer weight around/above 22 oz which should provide enhanced bolt contact dwell time with chamber and softer recoil over 5.4 oz buffer weight.

 

[markr6754]

Referencing more conservative lead and jacketed load data, if shooting test rounds at 3.0, 3.2, 3.4 and 3.6 didn't produce pierced primers, then you could ensure pierced primers never happen again with this particular combination of bullet/powder using mixed range brass - https://www.thehighroad.org/index.p...ppened-to-these-primers.914104/#post-12502787

And that's the thing with mixed range brass, we just don't know how many times they were reloaded and how much work hardening they experienced to expand with remaining malleability or not. Some of the cases experiencing pierced primers and some not could be the result of mixed range brass with different reload history.

Had the "plunk test" been done with AR9 barrel to perhaps use longer OAL, could have worked with higher 4.0 gr charge without piercing primers.

There's one way to find out ... Load some rounds longer to max/working OAL for the barrel/magazine and reuse the brass that produced pierced primers. (And I would also test 3.8 and 3.6 gr charges at longer OAL)

If no pierced primers with same headstamp brass at longer OAL and/or lower powder charges, then the rounds were overcharged.

That was my initial thought as well and was going to ask OP what the combined bolt/buffer weight was until I read buffer weight of 5.4 oz was being used (H3 buffer weight) and should bring the combined weight to around 20 oz and fall within ideal 20-22 oz for less harsh recoil and increased bolt contact dwell time with chamber - https://www.thehighroad.org/index.p...troke-bolt-for-9mm-pccs.913393/#post-12484268

​

Then OP posted

​

So heavier 7.5 oz buffer should bring the combined bolt/buffer weight around/above 22 oz which should provide enhanced bolt contact dwell time with chamber and softer recoil over 5.4 oz buffer weight.

Quite a collection of good ideas. I'll make up a new load ladder with the hated bullets specifically for this AR9. I'll start with a few dummy rounds to get the max OAL set, then build from there.

I have 20 offending rounds remaining with the 4.0gr 700-X load. The original source for this load was Hodgdon 124gr BERB HBRN which specifies 3.7gr to 4.2gr, at 1.150" OAL. Clearly, I deviated significantly when I replaced a plated bullet with a coated lead bullet, and then shaved a 0.080" off the OAL. As published the max charge would have been suitable, but there's no way of telling what the final pressure was. This case would also show that reading primers is voodoo, not science. I supposed that with beautifully rounded edges, these rounds were not subjected to excess pressure...but since the primer was clearly pierced, and may have been pierced and reclosed in the other rounds, that pressure did not force the primer back into the bolt face to flatten, if allowed the gases to go everywhere, and mostly back along the underside of the bolt carrier...which was thoroughly blackened on the extractor side of the carrier, while the opposite side was clean as a whistle.

Lastly, the combined BCG and buffer weigh 21.5oz. I can attest that it produced soft, pleasurable recoil...which should not be interpreted (as I did) as safe, fun shooting.

 

[LiveLife]

the combined BCG and buffer weigh 21.5oz. I can attest that it produced soft, pleasurable recoil

Very good.

combined weight to ... fall within ideal 20-22 oz for less harsh recoil and increased bolt contact dwell time with chamber

original source for this load was Hodgdon 124gr BERB HBRN which specifies 3.7gr to 4.2gr, at 1.150" OAL. Clearly, I deviated significantly when I replaced a plated bullet with a coated lead bullet, and then shaved a 0.080" off the OAL

While Berry's Hollow Base Round Nose is plated bullet, load data was produced using Thick Plated bullet (Like Speer Gold Dot/TMJ) which was meant to be driven hard at jacketed velocities.

• 9mm 125 gr Lead RN 700-X COL 1.130" Start 3.2 gr (920 fps) - Max 3.4 gr (977 fps) - https://reloadingdata.speer.com/downloads/speer/reloading-pdfs/handgun/9mm_Luger_125.pdf

• 9mm 124 gr Berry's HBRN-TP 700-X COL 1.150" Start 3.7 gr (894 fps) - Max 4.2 gr (1,068 fps) - https://www.hodgdonreloading.com/reloading-data-center

• 9mm 124 gr TMJ RN 700-X COL 1.135" Start 3.9 gr (989 fps) - Max 4.3 gr (1067 fps) - https://reloadingdata.speer.com/downloads/speer/reloading-pdfs/handgun/9mm_Luger__124_rev1.pdf

This "Thick Plated" load data is confusing for some reloaders as they may assume it could be safe to use for regular plated bullets but it should be treated as jacketed load data (Like Speer TMJ load data). As to longer 1.150" OAL/COL used for load data, that is likely from hollow base that extends the bullet base length and gets seated deeper in the case neck if same COL is used as with flat base RN bullet.

9mm with small internal case volume is more sensitive to small changes in reloading variables as illustrated by FMJ max charge being 3.6 gr due to shorter COL used. So when larger .356" sized coated bullets are used that will trap high pressure gas better than .355" sized bullets, 3.6 gr may be a practical max charge. And when even shorter 1.070" COL that seats bullet base deeper is used, why I suggested testing lower than 3.6 gr charges.

• 9mm 125 gr Sierra FMJ 700-X COL 1.090" Start 3.0 gr (845 fps) - Max 3.6 gr (1,007 fps) - https://www.hodgdonreloading.com/reloading-data-center

But since I have used lead load data for Hi-Tek coated bullets with good results, I would also reference Speer lead load data which used longer 1.130" COL with max charge of 3.4 gr which means using shorter 1.070" may produce reliable bolt cycling at lower charges.

• 9mm 125 gr Lead RN 700-X COL 1.130" Start 3.2 gr (920 fps) - Max 3.4 gr (977 fps) - https://reloadingdata.speer.com/downloads/speer/reloading-pdfs/handgun/9mm_Luger_125.pdf

Personally, if I was conducting powder workup at shorter 1.070" similar to COL used for MBC Hi-Tek coated bullet with nose profile that requires shorter COL (Or for barrels with short leade), I would use 3.0 gr and even 2.8/2.9 gr as start charge and test up to 3.2, 3.4 gr.

 

[markr6754]

@LiveLife - once again, very solid and sound advice. Your pic looks quite similar to mine. The Hi Tek projectile measures 0.563" while the CPRN round is 0.586". That longer profile allows me to chamber the CPRN rounds at 1.125" despite the 0.023" difference in bullet length. Ogives matter.

 

[markr6754]

@LiveLife I've determined that this AR9 Rosco barrel has quite the generous chamber. I loaded a couple of dummy rounds, seating the Hi Tek bullet to 1.166" C.O.L. It plunks. I started at 1.174" and it did not plunk...the bullet contacted the rifling. Then I seated (attempted 1.169") and it came out to 1.166". The round would not pass 2 of the 3 case gauges I have, standing proud by some 1/8", but it does fit in my Lyman Handgun Ammo block. It also sticks in my spare Beretta 92FS barrel, just a hair, as it does plunk, but won't turn in the chamber. Since that is my most generous handgun barrel I know it will stick in everything else. But no matter as this is a test of my AR9.

I'm going to avoid replicating the original load, not even using the same powder as I have no desire to puncture any other primers. However, rather than attempting to load these hated (by me) bullets to fit in my handgun chambers I'll dedicate them to this AR, working up loads with slower powders and seating them long, knowing they'll fit in this barrel.

When I cycled the 2 dummy rounds through the AR9, one of them shortened to 1.165" while the other remained at 1.166", thus I believe I have the taper crimp set about right. I may turn it another 1/8 turn just to be sure.

As to my 700-X, I love this powder...but I'll stick with the jacketed and plated rounds that I've used in the past and avoid using it with coated lead.

 

[markr6754]

As a final update on this thread I just returned from the range. I had a box of the 124gr HiTek bullets with 4.0gr 700-X and WSP loaded unusually low to 1.070" - my original problem load.

I also made up a 4 step load last night with 3.0gr to 3.6gr of 700-X in 0.2 gr increments. I intentionally seated these to 1.150" as they did plunk in my AR9 barrel.

First the shorties in my AR9 - they fired nice and sweet, so primer signs, no pressure signs, all cases look well struck, and the rounds were wonderfully accurate.

Next, I shot a magzine of them in my Springfield EMP. It turns out...THIS IS THE PROBLEM PISTOL. While there were no punctures, the firing pin strikes were all blown flat, as in the first set of pictures in Post #1. Furthermore, each following shot resulted in a click, no bang, cock the hammer, bang. I'm not going to troublshoot this further...clearly, this round is far too hot, the bullet seated far too deep, for safe and reliable shooting. I don't care if it is juts shooting paper...click, no bang is not fun at the range. Despite knowing that these rounds are eaten up by my AR9, I will not be repeating this load.

Now the longies:

3.0gr - I believe I could throw the bullet further. Unbelievably soft, very slow cycling, and although the round is accurate at 10 yds I wouldn't repeat this charge/COL combination.

3.2gr - better, a starting load, good cycling, decent felt recoil, quite appropriate for my wife or my grandson to use

3.4gr - this was a nice charge. Accurate, nice cycling, decent load for fun shooting

3.6gr - I expected this to be a bit harder hitting. It just felt right, but unnecessary for rtange shooting when 3.4gr seemed to do the trick.

My conclusion is that I was stupid to ever try 4.0gr and 1.070", and I won't swap a plated load for a coated lead load ever again.

Though I won't drag this on needlessly, I intend to repeat my ladder (save 3.0gr) and seat the bullets to the 1.125" COL specified in the manual. Since my AR9 seems to enjoy these rounds I'll plan to dedicate them to it, and avoid trying to make the rounds to fit in any of my handguns.

Thanks for the tips and advice along the way.

 

[GeoDudeFlorida]

These are some well thought out answers. I appreciate them, including the Magic Rabbit Foot reference. I've found that a Rubber Chicken works better, and doesn't maim any rodents.

Sorry for the interruption but I have to set the record straight: rabbits are lagomorphs, not rodents.
Carry on…

 

[chevrofreak]

Oddly I have only had this happen with light charges. When experimenting with loads for my PCC I found that a light load of slow powder (4.4gr of N350) with a light bullet (115gr) felt the best with the best dot tracking, but this was obviously supposed to be a very low pressure load but it resulted in almost every single primer being pierced like this. That was likely a completely different problem called detonation, and both can be equally dangerous.

 

[243winxb]

Springfield EMP. It turns out...THIS IS THE PROBLEM PISTOL.

124gr HiTek bullets

Bullet diameter needs to be smaller then the chambers throat diameter. If bullet is larger, the COL will have to be shorter, to chamber.

The EMP, being a 1911 type, may have an inertia firing pin. Meaning, after the pin strike on the primer, pin retracts immediately. This leaves room for the primer to flow into the firing pin hole, at high pressure. When over pressure, primer blanks.

Misfires. The action may not fully close, at times, if bullet diameter is larger then the chamber throat.

 

[243winxb]

Springfields are chambered tight, to work with jacketed bullet diameter. Toss in a FAT lead/coated bullet, it may produce issues.

https://castboolits.gunloads.com/sh...he-Chamber(s)-Just-As-Important-As-The-Throat

The other one was a Springfield EMP in 9mm caliber. This one came in and none of my dummies would plunk, none of his handloads would plunk, I pulled one of his dummies and the boolit was down to .353" on one side and in the case all eccentric. The chamber would take a .379" gage pin at the largest. If you subtract the .012" case walls from the gage pin's diameter, you come up with .355" which will be too small to perform well in the barrel once fired. His empty cases were .379" and barely fit in the chamber.

Dave Manson sent me a finishing reamer with the throat section made onto it so it cuts the chamber and the throat, which worked great in the chamber, after reaming, the chamber was .382" at the headspace ledge, which is perfectly acceptable. But after pinning out the throat it wasn't quite to my satisfaction so I used another modified Manson reamer, this one ground down from a 35 caliber rifle throater (cuts a larger throat) and I throated the barrel with this to get enough .358" freebore to finish the job.

This gun had been sent back to Springfield twice, and they either failed or refused to address the less than SAAMI spec chamber, or the issues the customer was having with it.

 

[markr6754]

The EMP, being a 1911 type, may have an inertia firing pin. Meaning, after the pin strike on the primer, pin retracts immediately. This leaves room for the primer to flow into the firing pin hole, at high pressure. When over pressure, primer blanks.

Misfires. The action may not fully close, at times, if bullet diameter is larger then the chamber throat.

I pulled the Springfield EMP firing pin out last night. Looks like I'll need a new one. The tip is etched/scored one one side. I did my best to capture the two views etched side and reverse of that. There is a slight groove and a bit of a point sitting just above. I may be able to smooth that out...but a new firing pin is in order. While I can't say for sure that this happened on this outing...it surely didn't help.

 

[Blue68f100]

Misfires can be due to the Ti firing pin setup. If I recall if your contact Springfield with the problem they may send you the needed parts to convert it to a std setup. Which includes a std steel/SS FP, FP Spring and Hammer spring. They have to run a very high hammer spring to get enough energy for the Ti FP. If this is for carry I would convert it any way for reliability.