Primer blowby - 9 mm handloads

[Stefano189]

I am relatively new to reloading and recently I had to return my Sig X-Five to Sig. I received a call back from Sig about a week later telling me there was some etching of the metal at the breech face around the firing pin because of hot gas escaping from around the primers which unfortunately I never noticed. I have spent considerable time trying to determine what the cause is and I look forward to any assistance from any readers who are familiar with this problem. Here is some history about how I've been reloading.

1) Initially I started reloading with Speer 115 gr. GDHP bullets (100) with 5.3 grains of Hodgdon CFE Pistol, CCI small pistol primers, COL 1.125 (Hodgdon recipe).

2) Hornady 115 gr XTP HP, 5.3 gr. CFE Pistol, CCI primers, COL 1.090 (Lyman recipe).

3) Hornady 115 gr XTP HP, 5.3 gr. CFE Pistol, CCI primers, COL 1.075; 2 failures to eject (Hornady recipe).

4) Hornady 115 gr XTP HP, 5.5 gr CFE Pistol, CCI primers, COL 1.075 (increased powder charge). I used 500 Hornady XTP HP bullets.

5) X-treme 115 gr JHP bullet, 5.5 gr CFE Pistol, CCI primers, COL 1.075. (2000 X-treme bullets).

6) I have used various cases such as Federal, Blazer, Winchester, Magtech, Speer, etc and have reloaded these cases between 12 and 14 times.

7) About 33% of these reloads exhibit "blowby" and I've decapped some of them and the primer pockets appear to be within specification but I'm not sure I'm measuring correctly.

8) I clean the brass using the stainless steel pin media (http://www.stainlesstumblingmedia.com/) and have checked the primer depth to find that the primers were not seated at or below .004" so I re-seated about a hundred primers to the proper depth. This had virtually no effect on the problem.

9) More recently I ran out of CFE Pistol and have started to use Alliant Power Pistol powder and have switched to Montana Gold 115 gr JHP. I haven't shot many of these so I have little data.

Any help with this problem will be greatly appreciated.

 

[Walkalong]

The primers don't show high pressure with no flattening at the edges.. One has a split that I would assume is from a bad cup.

Your primer pockets could be getting too loose. Was it super easy to seat the primers? Are there others with that split cup? Could be a bad batch.

 

[KansasSasquatch]

My first thought is that the brass is just used up and your primer pockets are just too loose.

 

[BigBore45]

i would call loose primer pockets aswell

 

[Rule3]

With a wonderful gun and "expensive" as the X Five I hope if new that you shot it first with factory ammo. Most manufacturers frown on reloads and if you are new to reloading and damaged the gun, well who knows what they will do??

If I ever buy a brand new gun (not often) I will run a box or two of factory ammo just in case something happens, then the can not blame me or my ammo.

Have you shot factory ammo through the gun, if so was there any problems?

If not than with the info given I would also say bad brass. But that said I have 9mm brass I have reloaded so many times and never experienced a issue like this.

Do you have the gun back from Sig??

My suggestion is try some factory stuff and get some new brass (from the factory ammo you shoot) or heck buy some.brass 9mm is cheap)

 

[243winxb]

Loaded 14 time & cleaned each time with SS pins = enlarged, loose primer pockets.

 

[Terlingueno]

How many grains of Power Pistol and what COL are you using with it?

 

[just for fun]

Well, Lad, that's a first and I started reloading in the mid 80's!What I've done in the past doesn't count or matter, it's your problem that is at issue. All have blamed the brass and I would agree if I knew that your primers were a name brand, as in "made in America". Can't blame the powder because different types were used. Could these loads have been built on "range brass"?
If your reply is Name Brand primers and You bought the brass new, then it's time to order more brass.
Judgement call on my part, but I don't see this as a headspace problem. If it were so the primers would start to look like small finishing nails OR not fully seated. (Really it's a case of being reseated in a fired round)

 

[judgedelta]

It would appear that you've gotten your money's worth out of that brass. It may have been loaded several times before you got it, if it was range brass. I have learned (to my embarrassment) that anytime I have problem with my reloads, I try to duplicate the symptom with factory ammo. Starline is awaiting your call...

 

[Rule3]

Loaded 14 time & cleaned each time with SS pins = enlarged, loose primer pockets.

Guess I missed that part, but I know I have brass loaded more than 14 times. I do not use those SS pins though But were they new to begin with or range trash?

) I clean the brass using the stainless steel pin media (http://www.stainlesstumblingmedia.com/) and have checked the primer depth to find that the primers were not seated at or below .004" so I re-seated about a hundred primers to the proper depth. This had virtually no effect on the problem.


I have never measured primer seating depth? I seat them till they bottom out. Done.

 

[gamestalker]

I run full tilt Longshot jacketed loads exclusively and have not had that happen. Yet, I'll get a split case mouth when the brass starts to reach it's life span, or I'll start to feel the pockets getting loose, but I don't get any gas leakage around the primers or pockets, as it were. But considering you have tracked the number of times the brass has been loaded, that being 14 times, I would be almost, not totally, but almost certain to look in that direction first. 14 times is a pretty good number of loads on any brass.

So if I were to guess, and that's about all any of can do at this point, I would put my money on either worn out brass, as in pockets have gotten loose.

Or the other possible, is bad brass. You didn't say which brass head stamps were exhibiting the failure, or if it was a mix of everything. The reason I bring this up, is I ran across some Federal brass lately that had loose pockets right out of the chute.

And something else I've thought about is the whole SS pins thing. I don't know how likely it is that SS pins could damage the inside wall of the pocket, I mean, they're pretty abrasive aren't they?

GS

 

[243winxb]

CFE Pistol,* Could it be a hot batch of powder??

http://www.thehighroad.org/showthread.php?t=788810

 

[ku4hx]

Not all brass is created equal; I'd go with worn out brass.

 

[rfwobbly]

It's most probably the brass. Speer is owned by ATK, who also owns Federal. Federal is known to have short-lived brass due to their alloy. It wouldn't surprise me at all to find they have the same brass throughout the corporation, just stamped several different ways. I'd order up some Star Line brass.

You might also start tumbling with the primers still in place.

Those primers look weird too. What brand are they?

 

[vaalpens]

This is one of those interesting threads that i will definitely follow. It is just strange that you you have that high a percentage of primer blowby, and primer blowby is not a topic that is discussed much.

I am hoping to learn a lot from this discussion.

When I started loading 357sig, I had some brass with bulging and the primers seated very easy. This had me concerned a bit. Even with the higher 357sig pressure, I did not see any primer blowby. Maybe I just missed it, but I will definitely inspect my cases more thoroughly before decapping and cleaning.

Can you post a picture of a round you loaded showing the primer and also the crimping?

 

[Sunray]

Was the brass new when you started? Or did you scrounge the range?
5.3 of CFE is the start load(you need to work up the load, not just pick one). Between 12 and 14 times is 13, but that shouldn't have caused the primer pockets to expand on new brass. Using range brass means you have no idea how old it is, what has been done to it in the past or anything else about it.
"...cleaned each time with SS pins = enlarged, loose primer pockets..." There any documentation that says that? Just curious. Don't see any advantage to SS pins myself.

 

[WMaximusD]

If you were using range brass or once fired brass did you swage (over-swage) the primer pockets?

 

[Stefano189]

My sincere thanks to all who have responded to this problem.

Here below are answers to questions that were asked by those of you who responded.

Walkalong: Over time it seems that primers inserted in Federal, Speer, and Blazer brass required less effort than those inserted in Magtech and Winchester brass. I think the “split” cup could be the result of a combination of re-seating the primers to .004” under flush and the aforementioned etching on the breech face around the firing pin.

Rule 3: When I first purchased the X-Five I probably ran more than 500 rounds or more of 115 gr., FMJ, factory ammo by Federal, Blazer, etc. with no apparent problem.
This gun has been back to Sig before; the first time the safety lever failed; the second time the rear sight came apart during a shooting session and both times the repair was carried out without any cost to me and no comment about the condition of the gun. The third time the gun went in for a replacement of the recoil spring; Sig would not sell it to me and that’s another story but this time I received a call from them about the etching on the face of the breech because of the primer blow-by.

Terlingueno: Currently I’m using 5.8 grains of Power Pistol with a Montana Gold, 115 grain, FMJ HP, COL 1.090. The bullet length is 0.555” which is .015” more than the Hornady 115 gr XTP HP (~ 0.54”) and has been accounted for in the COL.

Just for fun: I’m using CCI 500 primers almost exclusively except for one box (1000) of Remington 1-1/2 primers. I started reloading, in the main, with brass only one-time fired (mostly by me) from the manufacturers mentioned above.

Judgedelta: From the majority of the replies it appears the brass has reached end of useful life. As an aside one of the writers from Guns and Ammo reloaded a .38 special case 144 times until he noticed a crack in the case mouth. Of course this is a low pressure cartridge (2.7 gr. Bullseye / 148 gr. WC bullet) and there was no discussion about primer blow-by. I will run a couple of boxes of factory ammo through the gun and see what happens. I will also take a look at Starline as you suggest.

Rule 3: The brass was from one-time fired cartridges (by me) from manufacturers mentioned above. The failure rate was about 33% but weighted more towards Speer, Federal and Blazer. The SS pins measure .047” (3/64) x 0.255” and are used with water and a small amount of detergent and do a very nice job. While the pins could be a factor in the wear of the primer pocket, my sense is that it is second order effect. I thought that the primer seating depth was a factor but as it turned out the failure rate was almost identical for those cartridges whose primers were seated as you indicated in your reply, that is, “I seat them till they bottom out. Done.” I will not go through that exercise again. I did measure factory ammo, Blazer, Magtech and Fiocchi and factory ammo primers are seated between .004” and .007’ under flush but of course their system is mechanized.

Gamestalker: The brass used is mentioned in the replies above. Unfortunately being relatively new to reloading I’m not familiar with “looseness” in connection with primer pockets but I’m learning. As mentioned in a previously reply I’m not sure about the SS pins and their net effect on primer pocket wear. I haven’t seen any commentary on the SS media website or anywhere else for that matter. Maybe the media is too new and the jury is still out. Personally, I think the effect is secondary to the number of times the brass has been reloaded.

rfwobbly: The primers are CCI 500 almost exclusively except for 1000 Remington 1-1/2s. Speer and Federal had the highest failure rate as your comment supports. Tumbling with the primers in place would remove one variable but then that would entail a separate hand cleaning of the primer pockets. See my reply to Gamestalker above.

Vaalpens: I’ll put a photo of a loaded round in the next posting.

Sunray: The overwhelming majority of brass was from once-fired (by me) factory ammo. There were a few cartridges from the range but they were also only once-fired from boxed factory ammo. I started with the minimum load of 5.3 grains of CFE and after some shooting there were a few instances of failure to eject so I increased the load to 5.5 grains CFE and the problem was resolved. I loaded 2,525 rounds with 2 lbs. of CFE Pistol for an average load of 5.54 grains/cartridge. The SS pins work very well and as mentioned in the previous replies it’s not clear that they are having a first order effect on the primer pockets. I think the advantages are very clean brass, reusable media and ostensibly less time. Take a look at the website and let me know what your thoughts are. http://www.stainlesstumblingmedia.com/

WMaximusD: I didn’t use range brass and did nothing to the primer pockets; I started with factory ammo, fired it, decapped and re-sized the brass, cleaned the brass, expanded the case mouths (minimally), primed, added powder and seated and taper crimped the bullets.

At this point I’m going to follow the lead of those who have replied and scrap the brass I’ve been using and start over with factory ammo and watch very carefully for any primer leakage and blow-by. And thanks again for your input. I have attached a photo of the slide taken by Sig. It is an enlarged photo.

 

[243winxb]

Remington Primers

except for 1000 Remington 1-1/2s.

Use the Remington 5 1/2 primer. Something to watch, not sure its was your problem?? The other cartridges run at about the same pressure as your 9mm?? All 35,000 PSI. http://www.saami.org/specifications_and_information/specifications/Velocity_Pressure_CfPR.pdf

 

[Walkalong]

That is some bad etching. What is Sig willing to do for you?

 

[Stefano189]

243winxb: Given that I am a novice reloader I try to follow the recipe in the reloading manual as best I can. If you recall about a year ago or so things were pretty bad with regard to buying powder and primers and here in the northeast pickings were very slim and so one had to settle with what one could get, so following a recipe exactly was not possible. With regard to primers the recipe I was using called for a Winchester WSP (Winchester small primer) and the only primers that were available to me were CCI 500s (small primers). There seems to be conflicting views regarding primers for specific calibers and the information I used is contained in this link that I thought was informative. www.chuckhawks.com/primers.htm.

Walkalong: As mentioned the photo I supplied from Sig was really enlarged and the etching is really not as bad as it appears when you look at the slide. However, if you have additional comments with regard to the etching and performance of the gun or lack of same, I would appreciate hearing from you.

Sig did not offer any advice except to ask me if I wanted to replace the slide at a cost of somewhere around $400. Since the gun was shooting fine I didn't see any reason to change the slide.

As an aside, I've been wanting to put a red dot sight on this gun and I was told by the Sig Customer Service rep that Sig would shortly be making available a slide that can accept a red dot sight for several of its products (similar to the S&W M&P). If that slide becomes available I would probably buy one to replace the existing slide unless of course there are other factors regarding the etching that I'm not aware of that suggest the slide be replaced now.

Thanks in advance for any assistance you can provide.

 

[Stefano189]

vaalpens: As requested here are two photos of two cartridges with primers and also the cartridges shown. The primers on these two cartridges were reset to put them below flush which I had originally thought might be the problem but it's not.

Also there is a very mild taper crimp which is probably not visible in the sense that a roll crimp would be visible.

 

[ironworkerwill]

Did you bother pushing out any of the used primers? If so, Im curious to know if the primers with blow-by had torn or possibly beveled mouths. They may be too etched to tell.

 

[gamestalker]

I would be inclined replace that slide, if it were me. That etching is really deep, thus I would think it could contribute to further problems with primers getting cut or backing out far enough to allow gas leakages, or even a total blow out.

GS

 

[njl]

I remember some people having a similar problem during shortages when using (IIRC) small rifle primers in place of small pistol primers and low pressure loads. Your 5.3gr loads are the starting load according to Hodgdon's online data, and kind of low pressure for 9mm. Do you know if those loads tended to have primer blow-by more than the 5.5gr loads?

I assume, if you're wet tumbling with pins, you're decapping the brass first. I wonder if it's a combination of worn brass / loose / too clean primer pockets. Some primer residue to help fill any voids between the case and primer might not be such a bad thing.