Flash holes in handgun brass

[Longone]

I was just going through some 45 ACP brass that I got from an indoor range and couldn't help but notice that some of the flash holes looked bigger than others. I deprimed a couple and much to my surprise they were .098" compared to .070" of most all the others.

I have drilled out some rifle brass to see if there was an improvement in accuracy but handgun brass? It would hardly seem worth it, and with my handgun skills how would I know?

Is it safe to load these with the same powder charge as the other brass? Any +or- to using these?

Thanks, Longone

[Bwana]

Just load them as you would the others. I don't know if Winchester is still producing these for their "leadless" primers. At the pressure levels of the normal 45ACP loads they will be safe and can use any normal load data.

[Longone]

I really didn't think it was going to cause a problem just wanted to know if it was a common practice. I can't see myself having the time to do it.

Longone

[44man]

I have no answer. I do not understand it at all. What is important is pressure out of the flash hole against the primer and recoil shield or bolt. That comes from powder. Making the flash hole larger is just not right.
You really could get into over pressure at the primer.

[MtGun44]

I believe the large flash holes may be from lead free primer ammunition. I think I heard
that they needed a larger flashhole due to higher primer pressure than normal primers.

Differences (mixed) in flash hole sizes will not assist in accuracy. Depending on the load and
shooting conditions, you may not notice it, but if you have a max load of a fast powder
developed with a normal flash hole, I'd back off a bit with a larger flash hole to stay on
the safe side.
Bill

[Longone]

They are not exactly max loads, 5.0 231 w/Lyman 452460. I am in the process of making some up that are all "small" flash hole to try and see if I can notice a difference.

Longone

[markinalpine]

At one time Winchester had a comment in the FAQ section at their ammunition web-site that answered this question, but I couldn't find it just now. Anyway, they said the larger flash hole was used with their Win Clean handgun ammo (lead free primers and enclosed base bullets), and that it could be reloaded for regular loads with non lead free primers. I've also noticed that some Speer .45 ACP brass has larger flash holes.
Mark [smilie=s:

[ReloaderFred]

The larger flash holes were one of the earlier attempts at coping with the higher brisance of the Diazodinitrophenol (DDNP) priming compound. The increased speed of the explosion forced the primer out of the pocket much faster than Lead Styphnate priming compound does. By enlarging the flash hole, some of the pressure was bled off into the case as it ignited the powder.

Since the primer backed out faster and flattened against the bolt face faster, the case didn't have time to move back from the pressure of the burning powder and reseat the primer before it flowed out beyond the diameter of the primer pocket. They then tried crimping in the primers, which helped, but in the process they also found, as some European manufacturers had many years ago, that large primers weren't necessary for the small volume and powder charges of the .45 acp case. I have European .45 acp brass headstamped 1957 that contains Berdan small pistol primers.

As for loading the brass with large flash holes, unless you're a 50 yard Bullseye shooter, you probably won't notice the difference. The same goes for the small pistol primed .45 acp brass.

Hope this helps.

Fred

[Longone]

ReloaderFred,

I hope you just read that somewhere because I couldn't remember that word for more than a minute let alone spell it. I'm not even sure your allowed to use that word in public.

Thanks for the help.

Lon gone

[gandydancer]

The larger flash holes were one of the earlier attempts at coping with the higher brisance of the Diazodinitrophenol (DDNP) priming compound. The increased speed of the explosion forced the primer out of the pocket much faster than Lead Styphnate priming compound does. By enlarging the flash hole, some of the pressure was bled off into the case as it ignited the powder.

Since the primer backed out faster and flattened against the bolt face faster, the case didn't have time to move back from the pressure of the burning powder and reseat the primer before it flowed out beyond the diameter of the primer pocket. They then tried crimping in the primers, which helped, but in the process they also found, as some European manufacturers had many years ago, that large primers weren't necessary for the small volume and powder charges of the .45 acp case. I have European .45 acp brass headstamped 1957 that contains Berdan small pistol primers.

As for loading the brass with large flash holes, unless you're a 50 yard Bullseye shooter, you probably won't notice the difference. The same goes for the small pistol primed .45 acp brass.

Hope this helps.

Fred
show off

[ReloaderFred]

Some things just stick in my mind. Mostly frivolous stuff, but once in awhile it's something useful. I did have to write down Diazodinitrophenol, though. It's easier to use it's nickname, DDNP, since most people won't know what you're talking about anyway.

Besides, I hate to see people guessing at answers, when the correct answer is readily available..

Hope this helps.

Fred

[Longone]

As usual here, just ask a question and the vast pool of experience shows up to help out. Thanks to all who responded.

Longone

[44man]

The larger flash holes were one of the earlier attempts at coping with the higher brisance of the Diazodinitrophenol (DDNP) priming compound. The increased speed of the explosion forced the primer out of the pocket much faster than Lead Styphnate priming compound does. By enlarging the flash hole, some of the pressure was bled off into the case as it ignited the powder.

Since the primer backed out faster and flattened against the bolt face faster, the case didn't have time to move back from the pressure of the burning powder and reseat the primer before it flowed out beyond the diameter of the primer pocket. They then tried crimping in the primers, which helped, but in the process they also found, as some European manufacturers had many years ago, that large primers weren't necessary for the small volume and powder charges of the .45 acp case. I have European .45 acp brass headstamped 1957 that contains Berdan small pistol primers.

As for loading the brass with large flash holes, unless you're a 50 yard Bullseye shooter, you probably won't notice the difference. The same goes for the small pistol primed .45 acp brass.

Hope this helps.

Fred
Thank you, that is a great explanation.
I too found the SP primer is better in the ACP, best of all for the revolver.
Long ago shooting rubber bullets, I drilled flash holes to prevent backout and I keep them away from real boolit loads.

[ReloaderFred]

You're welcome.

I did point out to a friend when he was complaining about the large flash hole in the Winchester NT brass that he wouldn't have to drill out the flash holes anymore for his wax bullet practice in his S&W Model 25-2. His eyes lit up and the light bulb went on..........

Fred

[44man]

You're welcome.

I did point out to a friend when he was complaining about the large flash hole in the Winchester NT brass that he wouldn't have to drill out the flash holes anymore for his wax bullet practice in his S&W Model 25-2. His eyes lit up and the light bulb went on..........

Fred
Nice going. My problem was going through primers like mad. Darn, they go fast! :veryconfu