45 ACP flash holes very.

Longshot4

New member
I don't recall ever seeing any flash holes very in size as I did today.
I have a few hundred empty cases that I put through the nut shells over the weekend. So I thought I would size them and punch out the primers today. Wow! A lot of the flash holes very in size as much as about 50%. 200-300 WW cases had the most variations. Even the federal cases would jump around. I'm not talking about different size primer holes that I have herd of in the pass but flash holes. No wonder my accuracy varies so much. I didn't count how many were small or large but of the 400> cases there was a lot. Since I am one of those accuracy guys I suppose I will try sorting them out. Certainly I expect the sizes should be close to reduce fliers.

What do you think?
 
Since I am one of those accuracy guys I suppose I will try sorting them out.

Not needed, I use a 5/64th drill bit and ream them by hand to insure all media is removed and to uniform the flash holes. It also removes any burrs.

Stay safe.
Jim
 
Nobody that shoots action pistol competition worries about the flash hole. What distance are you shooting this 45 at?
 
I believe it would make a difference in a rifle. The 1000 yard shooters tell me everything affects everything. But a handgun?

I started shooting NRA Bullseye pistol this year and I missed the 50 yard target, not the bull or target center, the whole darn target, many times.

Handguns are very hard to shoot accurately and my hold and trigger pull create a lot more error than I see in my ammunition.
 
There is some 45 ACP brass out there with HUGE flash holes---it's made
for non toxic primers. Usually (but no always) the casehead will be
stamped NT. Regular flash holes will vary quite a bit, depending on brand
of brass and possible the phase of the moon.

I've never worried about it on 45 ACP or any pistol brass. Rifle brass
for long range or benchrest--yes.

99% of my accuracy problems with the 1911 pistol and 45 ACP reloads
have been caused by a loose nut behind the grip safety.:)
 
I have a flash hole gage. It was made long before NT 45 cases were made. The flash hole gage goes thought the flash hole without touching one side or the other. Commercial reloaders had a bigger problem with the large flash holes. The cases with the large flash holes had small pistol primers. All of the reloading equipment that was set up to load 45 ACP cases use large pistol primers.

F. Guffey
 
I realize that this loose nut would be the major accuracy issue. :D Although I must believe that by eliminating the physical flaws of the pistol and loads... I will increase the 10 ring hits.
As I cleaned the primer pockets on the federal cases I found about 30 flash holes that were normal size and 100> with obviously larger flash holes. I suspect the difference in flash holes were do to some of the factory rounds they came from were built with different specifications.
As I went through the Winchester cases I found the majority of the flash holes to be normal size or the same size as the majority of the Federal cases. Although I found about a half dozen of the Win. cases to have extremely large flash holes with only a lip for the primer to seat on. I will be sorting out the odd size flash holes nun the less.
I realize that a ransom rest would be nice to add to my tools for testing load accuracy but I also will need a new rod and reel for the Walleye jigging season coming up. ;)
 
It would be interesting to know what cases came from which factory loads. I wonder if they get into hotter/slower powders X the size of the flash hole for different reasons.
 
I would send a picture but I am not able to. The primer with the extremely large flash hole head stamp seas Winchester 45 AUTO and the normal size flash hole head stamp seas Winchester 45 AUTO. There is no NT on either head stamp. I will try to get out and try my Bullseye and Winchester primers with Winchester 230gr. FMJ this weekend. If I do I will give a report. I don't have a chronograph but I will do my best.
 
I'm getting back into 45auto again, cleaned the fired brass & also found the Federal flash hole much larger then the Winchester, R P & Speer. Last three are the same. Have close to 300 Federal cases all the same. Would the larger hole cause the powder to burn faster or more pressure? I never noticed it before, I must have been cleaning, reloading & shooting each brand separately.
 
I have noticed that flash holes don't very as much as they look like they do . I have found if I'm comparing them right after de-priming and there is still black residue in the primer pocket . That residue gives it a false look as to how big each flash hole is . I'm not saying there are not differences . Just that unless the primer pockets are clean and you can clearly see the defined flash hole edges . It's hard for me to tell for sure how big or small the flash holes really are .

I have found when I clean the pockets real well and hold them up to a light . The differences are often not as bad as they looked before cleaning and just looking at them with out contrasting light . To stump me even one further If I look at 3 or 4 at a time in the light then change the order and look again . The ones that looked bigger now look smaller . Not all the time mind you but enough to know ( at least when I'm looking at them ) I can't really tell just by looking which is which unless they are WAY off .
 
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About these 45 ACP Winchester cases. I don't think I explained the difference well. Since I cant send a Picture I will try to take some measurements. I took my basic DeWalt twist drill bit box with 29 bits from 1/16, 5/64, 3/32, 7/64, 1/8...

The smaller flash hole (standard size) is 5/64"
The seat or flat surface around the hole is very close to 5/64"<

The unusually large flash hole size is 1/8" witch if my calculations are correct is 3/64 larger than the standard flash holes.
The seat of flat surface around that hole is some thing less than 1/16" I'm guessing 3/64".

With what I have this is the best I can do.
 
I'm not sure the flash hole size on a 45auto is going to amount to much of any difference. I have played with the 45 rounds a bit and basically if your powder/bullet/primer all get along the brass doesn't matter much. I've gone through the pain of sorting by wall thickness variation for 45auto (a test of mine, NOT recommended;)), it made no difference in accuracy.
 
Longshot :

Those are some big differences for sure . I think even I would see that with my naked eye :)

brasscollector said:
I've gone through the pain of sorting by wall thickness variation for 45auto (a test of mine, NOT recommended), it made no difference in accuracy.

I did/do the same thing , how ever not for accuracy but to insure consistent crimp . The thinner walled cases ( PPU , Aguila , R.P. ) Will get almost no crimp if I leave my crimp die set the same as when I'm crimping Win , Fed , Speer cases . I actually had one of those thin walled cases slip through and was loaded with the thicker walled cases . I felt that bullet go through the press and could tell it did not crimp the same as the others . I marked it and kept track of it so I knew when it was loaded in the mag and when it was to be chambered . I got a feed jam and the bullet set back .070 .

HGk3ou.jpg


And that's why I'll keep separating my brass by wall thickness if I use mixed brass .
 
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