Flash hole size matter?

[HankC]

I have not reloaded any yet but every trip to the range, I pick up 308 brass when I see them, I notice the flash hole size difference is quite significant. Do you sort by flash hole size or even brass brand or does not really matter? Plinking, not competition shooting.

 

[Reloadron]

I have not reloaded any yet but every trip to the range, I pick up 308 brass when I see them, I notice the flash hole size difference is quite significant. Do you sort by flash hole size or even brass brand or does not really matter? Plinking, not competition shooting.

For plinking and not match ammunition I would not worry about it. Years ago when I was a little more OCD about every detail I would uniform flash holes but if there was any merit to it I never saw it. More a matter of diminishing returns unless you have one serious target rifle.

Just My Take....
Ron

 

[Steve C]

Years ago I tested some identical .45 acp loads using Win Clean cases that had the large flash hole and PMC cases with the smaller traditional size flash hole. My results are shown below. Conclusion, flash hole size makes no difference in average velocity in handgun reloads though there is a bit greater consistency in the loads using the Win Clean cases.

 

[Rule3]

The cartridge fired the first time so it must work.

 

[ku4hx]

I have not reloaded any yet but every trip to the range, I pick up 308 brass when I see them, I notice the flash hole size difference is quite significant. Do you sort by flash hole size or even brass brand or does not really matter? Plinking, not competition shooting.

I don't sort at all. I used to, but discovered the marginal gain for my purposes was nil. I have a shooting buddy into long range competition and I've seen first hand how sorting by case brand and lot IS an advantage. I never even considered sorting by flash hole diameter. How would you even do that? With tiny Go-NoGo gauges?

 

[GooseGestapo]

It can matter. Too large of a flash hole can cause the primers to be extruded into the firing pin hole and against the breech causing binding of the action. Most frequently seen with revolvers. (Cases modified for shooting Speer plastic slugs powered only by primers, flash holes drilled out)
Also, flash hole can be so small, normal decamping punches won't fit. I had this happen twice.
Once with Lee dies and Lapua brass in 6mm PPC. Factory PPC brass has smaller than standard flash holes. They require smaller decapper pins.
Second time was with some Sellier and Belliot .22Hornet brass. I gladly thinned my decapper punches. It's my most accurate Hornet brass.

But , like another poster stated, if it went bang without a problem, it's probly "OK".

 

[ku4hx]

Also, flash hole can be so small, normal decamping punches won't fit.

Been there; done that. I bought 1,000 Speer 357 Sig previously fired from brassmanbrass.com and discovered they had really small flash holes. Great brass at a good price just tiny flash holes. It took a few passes removing the primer to realize I was also repunching the flash hole.

Luckily, I managed to rig up a decapping die that worked. I seem to recall I later realized my Lee universal depriming die had the requisite size pin.

In this case, that anemic flash hole did make a difference in my loading protocol.

 

[mdi]

Everything matters when it comes to reloading, but how much depends on how much effort you feel is necessary to suit your reloads. I sort by headstamp (just outta habit, really doesn't make much difference) and in 30 years I've never measured a flash hole. I did "deburr" some in my .308 brass but I was just experimenting with the process. I haven't cleaned a primer pocket for any handgun brass in 29 1/2 years, and can't remember if I cleaned any pockets in my Garand or 308 brass or not, it just makes no noticeable difference in my reloads. But, if you wanna "resize" or ream flash holes it's really OK. If it doesn't suit you reloading/shooting needs then don't, it's OK too...

BTW; I haven't found any too small to deprime flash holes, yet...

 

[Dframe]

once in a while I find one that has burrs or is excessively small. I bought one of those "Uniformers" years ago and though I don't use it often it's damn handy when you have an overly small flash hole (the kind that can damage a decapping pin)

 

[Sunray]

"...Too large of a flash hole can cause the primers to be extruded into the firing pin hole..." How does a hole, that is nowhere near another hole, cause anything to happen?
Too large a flash hole can cause weird ignition of the powder, but it's not going to cause anything to extrude anywhere.

 

[Blue68f100]

The primer hole size works as a choke to limit pressure to the primer. If I recall the cup is rated some where around 40k psi before it fails. So on high pressure rounds it does matter.

Then they came out with the NT primers which required a larger flash hole. This caused primers to back out during testing. This is why most all NT primers are crimped.

 

[gamestalker]

I consider myself pretty OCD about reloading, but I don't usually do anything to the flash holes unless they have a visible defect, half moon holes for instance. But as long as they have a semi round hole, and they fired the first time around, I consider them good to go.

I do knock the ash out of the pockets, then give them a quick wipe with a Q tip dipped in some alcohol, done.

GS