Reloading tricks

Under normal circumstances and pressures, enlarging the flash hole will result in increased back pressure into the primer pocket with the resulting increased expansion of the primer, flattening, and expanding the primer pocket much quicker resulting in ruined brass.

The only times I have ever found it necessary to enlarge a flash hole is when loading and using revolver squib wax, plastic or rubber bullets for indoor gallery shooting. These handgun loads are powered solely by the primer pressure, and a normal flash hole without the powder charge pressure to reset the primer may cause the primer to back out and increase drag or lock the cylinder.

These case heads are marked by using a colored Sharpie or light spray paint and are NEVER to be used for regular loads.
 
Hi to all
Did have somebody any experience with this ?
A reloader guy told me to try to make hole larger ( 3 mm - 3.2 mm ) between primer chamber to powder chamber on the brasses and to use CCI BR primers.
What do you think ?
Will help on something ?
I mean accuracy or other + things
Or will make something wrong to the gun or the bolt ?
For me i have interest for this calibers:
30-06
300wm
Don't do it. Will not affect accuracy except to make it worse and will waste a lot of time. Best barrels, best components and good gear that is properly used will make good ammo and ultimately good accuracy and precision.
 
I was just reading about that subject in "ABCs of Reloading" book. They say that enlarging primer pilot hole will result in faster ignition and more pressure. That makes sense to me so I have to agree that messing with pilot hole diameter is a bad idea. The book also advises against it
Wow, I'm suprised a publication to suggest something that could land them in a law suit if someone loses half their face!
I mean if you want a larger ignition then I would look into what primers you are using as they are not all the same or equal, even in the same size!


Primer Flash Test Photos

CCI BR4 Small Rifle

GASCCIBR4SR.jpg


CCI BR2 Large Rifle
GASCCIBR2LR.jpg


Federal 205m Small Rifle (1980s Vintage. Current 205m flashes much more.)
GASFed205mSR.jpg


Federal 210m Large Rifle
GASFed210mLR.jpg


PMC (Russian) Small Rifle Magnum
GASPMCSRmag.jpg


PMC (Russian) Large Rifle
GASPMCLR.jpg


Remington 7.5 Small Rifle
GASRem75SR.jpg


Remington 9.5 Large Rifle
GASRem95LR.jpg


RWS (German) Large Rifle
GASRWSLR.jpg


Winchester Large Rifle
GASWWLR.jpg


If anything even moving to a magnum primer would be better(or less dangerous) than opening up the flash hole imo, as long as your working up of course & actually some powders(mainly ball type) recommend magnum primers in standard cartridges for better ignition!
 
Aushunter1,
Actually the book I was reading specifically said you shouldn't ever enlarge a primer pilot hole. I apologize that I didn't make myself clear on that.

From what I gather, enlarging a primer pilot hole would lead to faster ignition so that would be like switching to a faster power without any clue about load data.

PS - that is fascinating about the different primer ignition pics!!!
 
I tried enarging the primer hole years ago and found that accuracy was extremaly poor.
 
there is a minimum and maximum Flash hole diameter.

best I can tell the below is correct:
with that being said I have took a drill bit with this diameter and checked all my brass flash holes for consistency.
if they are to big I trash the brass if they are to small I will enlarge to meet the spec.
just want everything consistence.

with that said if you buy good brass you
typically don't have to worry about it.


SAAMI spec. for rifle cases using the large primer is 0.078" - 0.082"

Small primer pocket rifle and pistol cases use a smaller flash hole size of .074" - .078"
 
I cannot see where this is a solid idea. When creedmoor small primer brass hit the streets, a lot of people failed to buy different decapping pins, and ran large decap pins through the small flash holes. I have not read one favorable result when it was done.
Like mentioned above, you are inviting more pressure coming into the pocket.
 
Several years back I read a lot about drilling flash holes to 9/64" for subsonic loads.
 

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there is a minimum and maximum Flash hole diameter.

best I can tell the below is correct:
with that being said I have took a drill bit with this diameter and checked all my brass flash holes for consistency.
if they are to big I trash the brass if they are to small I will enlarge to meet the spec.
just want everything consistence.

with that said if you buy good brass you
typically don't have to worry about it.


SAAMI spec. for rifle cases using the large primer is 0.078" - 0.082"

Small primer pocket rifle and pistol cases use a smaller flash hole size of .074" - .078"
I also have done the same with great success. Now that most of my brass is ADG,Lapua, Alpha or Peterson I no longer have to do this.
 
There is no need to drill anything out. There is engineers that get paid way more than us "standard shooter" to test this stuff. I have never needed nothing more than playing with different primers good make something shoot unless there was an anomaly with a barrel issue. My rule of thumb over the years is 55 gr or powder up is magnum primers, less than that standard rifle. Ever one time have had a issue. Don't get caught up in the small stuff if your reloading practices are on point primers is just another course adjustment u can play with.
 
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Absolutely don't do that! In my muzzleloader if the flash hole in the nipple is getting enlarged from use I replace it because of the blowback of gas near your face. I can only imagine how much 60,000 psi gas can push on that primer through a 4 times larger flash hole.
 
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