Flash hole uniforming?

Hespco

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My hunting rifles tend to shoot 3/4" & under , some 1/2" & under. I'm using off the shelf Win & Rem brass. I don't segregate my brass by weight. I am not a competitive shooter. My question is , would I be waisting my time to uniform the flash holes in my brass? Your thoughts ? What is there for me to gain ? Of course I do like to tinker.
 
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For most it is an anal exercise BUT You only do brass prep once (except perhaps trimming).

Once done (FL size, trim, chamfer, uniform primer pockets & flashholes and then segregate by weight) You're starting with a good baseline.

OR you can buy Nosler brass that comes fully prepped.
 

MagnumManiac

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I do this on ALL of my brass, no matter the cartridge.
I have seen better consistency over the pressure trace between flash holes left as is over ones that were deburred.
Start pressures are more uniform with the funnel shaped entry to the powder column.
This is noticeable on target at distance with a fine tuned rifle and may not even be noticeable in a hunting rifle at less than 300yrds. If it is a tack driver though, it may just be worthwhile.

It won’t hurt nuffin to try.

Cheers.
 

MNbogboy

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My hunting rifles tend to shoot 3/4" & under , some 1/2" & under. I'm using off the shelf Win & Rem brass. I don't segregate my brass by weight. I am not a competitive shooter. My question is , would I be waisting my time to uniform the flash holes in my brass? Your thoughts ? What is there for me to gain ? Of course I do like to tinker.
Remington brass has shown me in many calibers the most and largest flashole burrs.
Uniforming just for that reason may make a difference.
However, depending on which style of uniformer you use, those that index off the neck require that each case be the same length in order to truly uniform the case. Sometimes it takes two or more firings to allow for consistent case trimming. Trimming new cases to equal length may be shortening cases to less than optimal length.
Just a couple things to think about. I trim every time after two or three firings. I use a cheap Lyman flashole uniformer after the second firing. Every fifth or sixth firing i may run the flashole tool in again to "clean" any built up carbon.
 

elf

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Most flash holes are punched in, leaving ragged inside burrs. Its OK to remove those burrs, but do not attempt to increase the diameter of flash holes. I have tried it and lost accuracy completely.
 

Vol1975

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Feb 6, 2017
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southeast
My hunting rifles tend to shoot 3/4" & under , some 1/2" & under. I'm using off the shelf Win & Rem brass. I don't segregate my brass by weight. I am not a competitive shooter. My question is , would I be waisting my time to uniform the flash holes in my brass? Your thoughts ? What is there for me to gain ? Of course I do like to tinker.

i general just take a look and if one looks out of size I check the size per Sprc.
sammi spec are as follows:
Standard flash hole specifications (SAAMI)


Large (rifle or handgun) primer: 0.080" +/-0.002"

Small (rifle or handgun) primer: 0.076" +/-0.002"

5/64" drill bit equals 0.0781"
i bought Several drill bits and keep them laying around for an easy check. If they are to Big i trash them. What I have found is they have to be shot a lot to be to big.
I did a test years ago on increasing my flash hole size a bit and what I found was it changed my group size once the hole was larger than the avg size. I want to say that when I went fairly large over flash hole size is when I seen a difference.
that my 2 cents.
 

jdyoung

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Ironman Country
I de burr the inside flash hole because sometime I will have a case with the inside burr large and sloppy enough to really interfere with the ignition of the powder. Then I would be scratchin’ my head wonderin’ WHY. So I check the box on that factor and move on (satisfied I just saved/made myself $.50 -$.60 per case). It has become principal part of my brass prep – uniform primer pockets, de-burr inside flash hole, check length, chamfer inside and outside case neck, burnish internal case neck.
 

RT2506

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Jan 10, 2008
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2,143
I do this on ALL of my brass, no matter the cartridge.
I have seen better consistency over the pressure trace between flash holes left as is over ones that were deburred.
Start pressures are more uniform with the funnel shaped entry to the powder column.
This is noticeable on target at distance with a fine tuned rifle and may not even be noticeable in a hunting rifle at less than 300yrds. If it is a tack driver though, it may just be worthwhile.

I agree 100% with this statement. I have experienced the same results.
 

BrentM

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Jan 10, 2013
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Location
Meridian, Idaho
If you don't weight sort brass to some extent, you'll never notice any improvement from uniforming primer pockets.
If you mean weight sort by H2O volume them yes. If you mean by case weight then no. There is no correlation in brass weight of same head stamp and lot vs volume. I've done this exercise many times and often a heavier piece of brass will actually have more volume. Reason, because the bulk of the brass is in the base and head where it is stamped.
 

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