First Post on Boolits- How to ENLARGE diameter of pistol case flash hole

Although I have heard about some high quality factory ammo with cases having smaller than average flash holes- perhaps European in origin, I have never seen any first hand. My wife picked some 9mm brass at the local range. It appeared to be a very good quality case. The brand was "NORMA". When I started processing a mixed lot of my own and a few extra range pickups, I ran into a brick wall when it came to these Norma cases. Ended up bending a de-capper pin. The flash hole is very narrow. These appear to be from factory ammo and had only been fired only a few hours before the wife found them. The good news is my wife will do anything to lower my "gun" spending and has embraced reloading! Bad, is these very clean cases seem to be designed with this very narrow flash hole. To be clear, there seems to be no burrs or other debris, no dirt or powder residue. The brass DOES NOT have military crimps.
While it seems the reloading tool companies seem to provide almost every tool needed [and sometimes not so needed] to process your reloads, I could find nothing to address this. A narrower de-capper pin would be much more easily bent and a special purpose de-capping die is not worth the bother. I would like the more experienced reloading members here how they would handle the issue.
I have found several hand tools to remove burrs and create a "uniform" flash hole but almost nothing to directly address this issue. The closest tool I could find is from Lyman. On page 44 of their 2022 catalog, Lyman shows two tools in the case prep tools & accessories section. One is a simple "flash hole cleaner" that appears not to be the answer. But a second tool with the same screw driver form, may have more potential and may be able to "drill out the hole". This is called a "flash hole uniformer"- #777750, price $18.95. From the listing it appears to have a small drill bit at the tip but I cannot tell from the picture if this tool would enlarge the entire hole to US specs. I NO NOT want to get involved in drilling out the hole with a drill press as it I think a error could cause over or under pressures that might cause malfunctions or worse.
Would love to know how you guys handle these abnormal cases. Thanks in advance!

The Lyman tool to use is #729748

It will both drill the hole and deburr the inside of the case. I place it in a drill press at a slow'ish speed (about 250 RPM). Works a treat.

Also, double check that the flash holes are centered, this too causes bent de-capping pins. Doubtful with Norma brass, as their stuff is on the up & up side of the house. But doesn't hurt taking a quick look at each piece of brass.

45_Colt

Measure your deprimer pin and get a number drill one size bigger and drill the primer flash holes using a hand drillmotor. You are not going to raise pressure by opening the primer flash hole by a couple of thousands.

I have a good variety of HHS and carbide drills on hand (lifelong machinist/mechanic) so I would follow rbuck351's advise. If a drill is not handy, take the depriming stem to your local ACE hardware and purchase a drill slightly larger than the stem. Shouldn't be more than $7.00-$10.00 for a good one.

Thanks for the quick reply/ help
The holes in these Norma are perfectly centered. I have the issue with some no name stuff I have come across. I just throw those away. I tried product # 729748 on the Lyman site with no luck. Perhaps it has been discontinued. Do you have a description. The tool I mentioned would be a hand tool of course. I have a Lyman case machine and attachments from Lyman and other companies for this machine. So I suspect your Lyman product was made for this machine. Perhaps the tool bit has been updated? See my reply below.

I really appreciate the come back. I have a collection of very small drill bits and your advice appears spot on. I can use the existing hole as a pilot so to properly center the bit but I was worried a little if I got the hole a little off center at the top of the primer pocket and that might me enlarged a little every time I de-cap the case. Probably over thinking it.

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Originally Posted by rjallen

Thanks for the quick reply/ help
The holes in these Norma are perfectly centered. I have the issue with some no name stuff I have come across. I just throw those away. I tried product # 729748 on the Lyman site with no luck.

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Here it is on Midways site:

https://www.midwayusa.com/product/101288179?pid=729748

Shows as available. I too checked Lymans site, and no go there. But they don't show a lot of what they actually sell.

45_Colt

First, thank you to 45 Colt, mdi, rbuck351. You really know how to make a guy feel welcome
I solved the issue thanks to all of your advice. First, 45 colt we were talking about the same tool, the reason you could not find it in Lyman it is listed as #7777760. I will pick this tool up from Midway. Thanks.
I did not have a drill bit that matched my Hornady small primer decap bit. This bit measured .0685.BUT! I did have an 1/"8 bit which measured .06085. The 1/8" bit was still bigger than the flash hole in the Norma 9mm cases. So, I drilled out the case's flash hole, then used the decapping pin to "swage out the hole. Although I cannot recommend this as best practice it did decap the brass and enlarge the hole to match the rest of my brass. My the way as most of you probably already know, there is no SAMMI size for flash holes. The diagrams for the shells do not give any information as to the flash hole size. Sure there is a story here.
Thanks again everyone. Brass now sized and de-capped.

Most of my pistol loading is done in mixed brass especially 9mm on progressive presses.

Instead of inspecting and drilling out the small ones I just turned down the decap pins. Don't take much.

I have the Hornady version of the tool you’re looking at, they don’t really enlarge so much as clean up the hole from the punching/piercing operation. 9mm brass is so plentiful around here so I just move anything odd to the side and load something else.

Just a thought, what die set are you using? Sometimes just switching to a different de-caping die may work. Not all primer pins are the same size

I've run into Norma 9mm brass as well. If I lightly lube the cases I find the Lee "U" die I'm using gets the job done. There is more resistance when sizing but I've yet to bend a decap pin.

I am sizing as well as de-capping. I only had 15 Norma brass cases. I use a standard Hornady sizing /de-capping die. I lubed the cases on my first attempt and managed to de-cap one case before breaking the pin. I agree with you that think it is really not worth the effort but it was an adventure in learning. Thanks all.

Are you sure the problem is the size of the flash hole? I bought some once fired 6.5x55 Norma military cases and the primers were crimped in place. I broke a couple of de-priming pins because of that. I then got a Lee universal de-primer and that did the job.

As Greg said, could the primers be crimped in?? My first action would have been to try an RCBS primer crimp remover. It doesn't "remove" any material, it just moves it. No chance of damaging the brass.

The lyman tool with the pilot and drill bit tip is the ticket..enlarges and deburs.

I think rjallen can report back to us when he receives his Lyman tool on whether the center finder portion of the drill resizes the flash hole enough or not.

I use that tool on ALL my metallic brass save for one cartridge (6 mm BR). I have left my Lapua brass in that cartridge flash holes small on purpose because it is part of the intent to have a restricted hole for accuracy. (I need to order a different debur tool for those cases and have not gotten around to it yet)

Deburring your flash holes on the inside will also help center your decapping pin (should reduce breakage) provided your pin fits the hole in the first place.

Three44s

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Originally Posted by GregLaROCHE

Are you sure the problem is the size of the flash hole? I bought some once fired 6.5x55 Norma military cases and the primers were crimped in place. I broke a couple of de-priming pins because of that. I then got a Lee universal de-primer and that did the job.

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I believe I have seen three or four different forms of crimped brass. The underside of the Norma cases were wide open, the primer was only friction fitted. I do think it would have been a good idea to try a Lee Universal De-capping Die. I am also curious about some of the very robust de-capping dies promoted on You Tube but before this the sizing / de-capping dies found in my various die sets worked very well. I have dies from RCBS, Lee, Redding as well as Hornady. From my limited experience I do agree with other posters the RCBS de-capping die seems to work a tad better when it comes to de-capping.

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Originally Posted by metricmonkeywrench

I have the Hornady version of the tool you’re looking at, they don’t really enlarge so much as clean up the hole from the punching/piercing operation. 9mm brass is so plentiful around here so I just move anything odd to the side and load something else.

Just a thought, what die set are you using? Sometimes just switching to a different de-caping die may work. Not all primer pins are the same size

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You so are right! The de-capping pins do vary a bit in size and I think the steel alloy differs as some pins are more rigid, others more flexible.

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Originally Posted by Three44s

I think rjallen can report back to us when he receives his Lyman tool on whether the center finder portion of the drill resizes the flash hole enough or not.

I use that tool on ALL my metallic brass save for one cartridge (6 mm BR). I have left my Lapua brass in that cartridge flash holes small on purpose because it is part of the intent to have a restricted hole for accuracy. (I need to order a different debur tool for those cases and have not gotten around to it yet)

Deburring your flash holes on the inside will also help center your decapping pin (should reduce breakage) provided your pin fits the hole in the first place.

Three44s

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I will sir. After my drilling / swagging efforts, I realized I had nothing to clean up the flash holes. Don't this would be needed for every cartridge case, especially for pistol ammo, but very needed when you have to drill or do other such excavations with in case.

I do all my de-priming using a Lee Classic punch before cleaning my brass, and have noted Norma brass, particularly 38 special and 357 mag, have tight flash holes also. The pin will punch the primer out but I often have to resort to using pliers to pull the pin out of the case. There is another manufacturer (can’t recall if it’s CBC or PAC) that also has tight flash holes.