Flash hole too small?

[tlawler]

What do you do when the flash hole is too small for easy depriming? I ordered a quantity of once fired .357 Sig mixed brass and I’m in the process of decapping it on my Lee APP. All of the Speer brass has flash holes that are too small for the decapping pin to easily pass through. At first I thought it was tight primer pockets, but on the few I’ve managed to decap, the pin is still very tight in the flash hole. The APP is great for fast decapping, but it’s a little flimsy, so I haven’t tried to force them. Luckily, the Speer only make up about 10% of the total so far.

What does one do in this situation? Scrap the brass? I’m using an RCBS universal decapping die…do they make a more slender decapping pin?

 

[GB]

My solution was to take the pin and chuck it up and apply some emery paper and maybe a fine file and reduce the diameter of the pin. Small holes are common on many European boxer primed cases. HTH

 

[ReloadforFun]

Check with RCBS. I think they do offer a smaller diameter decapping pin.

Sanding down the pin you have, as mentioned above is also viable.

 

[czgunner]

I bought a Lee reduced diameter pin for my universal decapping die.

Sent from my Pixel 3 using Tapatalk

 

[tlawler]

Thanks for the replies. I’ll try chucking the pin in my drill press and using sand cloth to mill it down some. Has anyone tried opening up the flash hole with an appropriately sized bit, so you won’t have to sort through them before decapping next time? After going through all the cases, it ended up being 25% or better were Speer.

On a positive note, I found eight FK Brno 7.5 cases mixed in, so if I ever decide to add another caliber, I’ll have a head start

 

[Alk8944]

What does one do in this situation? Scrap the brass? NO. If the flash holes are too small just drill it out to .080" (5/64" or #47 AWG drill) once you have the case de-primed, then it will be just like other normal brass.

 

[tlawler]

I milled down a pin and it did work. With the smaller diameter, I managed to poke right through a few primers without removing them…only a handful, so not a big loss.

What does one do in this situation? Scrap the brass? NO. If the flash holes are too small just drill it out to .080" (5/64" or #47 AWG drill) once you have the case de-primed, then it will be just like other normal brass.

I’ll give that a try after I wet tumble them. It seems a bit tedious, but if I can do it rather quickly with the drill press, I’ll see it through to the end. I hate wasting brass. I’m not sure how to hold them while drilling without damaging them. Maybe channel locks with a strip of leather in the jaws?

 

[GypsmJim]

Been there, done that. I had an old Lee Loader (whack-a-mole) that had a decapper that was a single "rod". I milled the tip of the pin at a 45 degree angle, without changing the diameter. I deprimed with a pin that was ground to a smaller diameter. Then, chucked up the 45 deg pin in a drill mounted sideways in a vice, running at full speed. Merely push the cases over the pin and viola they will be enlarged to the proper size. Wear a glove.

 

[Model19man]

I bought a box of 50 unprimed 32 WCF BLANK cartridges. The flash holes were quite small, and the brass was too long. I trimmed the brass and enlarged the flash holes with a #60 drill bit. They work fine now.

 

[BLUEDOT37]

If the flash hole is too small (& not the depriming pin too large) then use a flash hole uniformer to fix it.

All too often I've found various pieces of brass that have holes too small.

This tool will open it up to .080" & de-burr it as well.

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[tlawler]

In addition to being harder to decap, would undersized flash holes also affect performance of the primer? It seems like they would make it more difficult to achieve proper charge ignition as compared to a flash hole that allowed more “spark” from the primer.

 

[venomballistics]

Thanks for the replies. I’ll try chucking the pin in my drill press and using sand cloth to mill it down some. Has anyone tried opening up the flash hole with an appropriately sized bit, so you won’t have to sort through them before decapping next time? After going through all the cases, it ended up being 25% or better were Speer.

On a positive note, I found eight FK Brno 7.5 cases mixed in, so if I ever decide to add another caliber, I’ll have a head start

Yes ... flash hole modification is sometimes found among benchrest shooters. They will drill to make them uniform. chamfer, debur, port, polish, blueprint and balance like race engines.
It's not sacred territory, but aside from your current needs, there's little advantage to it.
Find a bit to match your normal flash holes and man the drill press.
RCBS decapping pins are replaceable, so turning one down is not a big deal

 

[H Richard]

A friend of mine that does a lot of reloading has shown me a number of cases with "Off Center" flash holes. These have caused more problems, and frequent of foreign cases.

 

[WR Moore]

Having bought a batch of Lapua .308 brass with small primer pockets and flash holes I've had a similar problem. The quickest solution is a Lee "undersize" flash hole decapping die #91976. About $13.

I did grind down an RCBS .22-.25 pin to work. I can't believe I'm gonna do it, but I'm gonna splurge and throw some money at Lee for a long term solution.

 

[mtgianni]

Several shooters using cast in rifles have opened the size of the flash hole in brass. The warning is to be very careful in marking them as a full pressure load now has an increased gas passage to the primer making pressure signs impossible to read. You also have more gas than a primer was designed to deal with and it may pop and release pressure back through the bolt.
Change pin size not primer holes.

 

[Greyman50]

Have only found smaller than standard dia. primer holes on “ furrin brass”.

 

[tlawler]

It was somewhat time consuming, but I drilled out all the Speer brass. Wasn’t too bad once I got a system going. I started out holding the cases with a pair of channel locks with a thick strip of cloth around the case, but then I realized the channel locks didn’t really make much of a mark on the brass with no cloth and it went pretty quickly after that.

Several shooters using cast in rifles have opened the size of the flash hole in brass. The warning is to be very careful in marking them as a full pressure load now has an increased gas passage to the primer making pressure signs impossible to read. You also have more gas than a primer was designed to deal with and it may pop and release pressure back through the bolt.
Change pin size not primer holes.

I actually drilled them out smaller than the other .357 Sig that I had decapped.

A drill size of .080” was mentioned. I had .0775” and .0925” available, so I went with the smaller bit after checking that it fit rather loosely in the flash holes of the brass I decapped with the standard diameter pin. I drilled a few out and made sure that a standard decapping pin fit through the new flash hole. I’ve got them all primed and ready for loading now.

 

[tlawler]

Have only found smaller than standard dia. primer holes on “ furrin brass”.

These were all Speer headstamps.

 

[WR Moore]

Given modern powders & primers, there are alleged advantages to the smaller flash holes. Particularly overseas, they seem to be much more common especially in brass for precision shooting. Ad copy for depriming tools suggests they're common here for .17 and .20 caliber rifle cartridges. They'd seem to make a lot of sense in short, stubby cartridges like the PPC series (I think they use them?) and 9mm/.40/.357 Sig.

In my very limited load workups for .308, it appears the small flash hole doesn't allow as much gas into the primer pocket, so trying to use primer condition as a pressure indicator as we're used to (OK, I know it's crude) may not work. Case volume and other factors are in play here, so that's not carved in stone.

 

[Nevada Ed]

I hate to say it but;

in todays world, not all of the primer holes are drilled "Dead Center" of the case......

and not all are perfectly round.

A fat primer punch, is looking at a short, life time.