6BR Lapua Flash Hole/Decapping Pin

[Flouncer]

Searched and read. Admonished to start new thread as all extant threads were more than 120 days old....

From the site section on 6BR, seemingly contradictory information:

About flash holes–we suggest leaving them alone when using Lapua brass. Our tests suggest that ES and SD may increase with ANY modification of the Lapua Flash-holes, which run 1.50mm (.059″) out of the box.

However, recent lots of Lapua 6BR brass have shown a few cases per box where there is a little flake of brass on the edge of the flash hole. You’ll want to pop this out. A Pin Vise with #53 or 19/32 bit works well for the job. If you do decide to actually ream the flash hole, use a K&M or Sinclair deburring tool for small primer holes–but be gentle, don’t ream the hole out. Double check the diameter of the cutter tip before reaming–some are oversize. To uniform the outside of the hole you can use the Sinclair 07-3000 outside PPC/BR flash hole reamer (right). This will ream the hole to about .064″ or so to fit a standard 1/16″ (.0625″) decapping pin.

Pretty sure I want to leave the flash hole stock at 1.5mm or 0.059". Who do you recommend for a suitable pin to use in the Lee, Lyman, RCBS or Hornady decapping dies ? I spoke with Lee. They don't make a small rifle pin that will fit the Lapua holes, and they recommended reaming the hole out. Negatore on that. That leaves the others. Any suggestions ?

All this because I wish to pop the spent primers in a separate single stand alone operation so I can effectively clean the cases and primer pockets.

 

[Heavies]

On my lee dies, I disassemble the die, chuck the center in a drill(being careful not to mar it), and carefully file, sand, and polish the pin until it fits through the hole without rubbing.

Otherwise Redding S dies come with the correct size pin.

 

[hogpatrol]

+1 on the Redding. Use them and it's a non issue.

 

[Flouncer]

Hog and Heavy, thanks for the advice. You confirm what I was thinking. I have Redding dies. But the pin is also the expander plug or rod. No great event there, but if I want to just knock the spent primer out, I'll just go with the $12 Lee die and carefully reduce the pins. They're inexpensive so I can afford to make a mistake or two.

 

[hogpatrol]

Hog and Heavy, thanks for the advice. You confirm what I was thinking. I have Redding dies. But the pin is also the expander plug or rod. No great event there, but if I want to just knock the spent primer out, I'll just go with the $12 Lee die and carefully reduce the pins. They're inexpensive so I can afford to make a mistake or two.

When I bought my 6br Redding dies, they had the large pin. I called them & they shipped me the decapping rod and a few extra small pins no charge. Customer service is great. Give 'em a call. Hog

 

[Shynloco]

Flouncer,
I've been through all that and might make a suggestion on what to do. When I get new Lapua brass (which is all I use anymore) I clean out the flashholes (internally and externally) just to be safe using an K&N Flashhole deburring tool that is adjustable for all calibers. As far at the flashholes sizing, l leave it alone and use a Wilson Neck sizing die to remove spent primers that comes with the appropriate sized decapping pin for the 6mm casing. Now I do use the Redding FL Sizing die, but have removed the expander ball/w pin to resize the fired casing to whatever bump the shoulders need (usually .001 - .002). Lastly I use a Sinclair Mandrel die to size all the necks so as to give best and uniformed necks and concentricity in rounout when the bullets are finally loaded. This process is pretty much error free and you don't have to play games with those pins and the smaller decapping pin that the 6mm employs. Just something to consider.

 

[NorCalMikie]

Get the proper size pins and be done with it. 8)

 

[Leaddog]

I use the Lee universal decapper. I ground the pin down to the correct size for the small flash holes. I now use this for both large and small primer decapping. The Lee is a tough unit and there is no way you will break the pin.

I prefer to decap before cleaning my cases using stainless steel media. I've removed the pins in all my resizing dies.

 

[eww1350]

For what it is worth...I tested several flash hole sizes on the Lapua BR case...062", .070", 075", and .080"
I found that the .062" flash hole does not hold an accuracy advantage over the lager flash holes up to .075"...in fact I get a better standard deviation with the .075" than the .062"...the .080" becomes a powder leaker on some of the smaller ball powders so I would not use it for that reason...I currently shoot short cut tubular type powders and the .075" is my choice...

Just my personal test results...

Eddie in Texas

EDITOR: Eddie may have had good results, but I absolutely advise against this. Please read my post later in this thread. For a number of reasons, I strongly recommend that you NOT ream 6mmBR brass flash-holes to a hole size significantly above 0.062". And be aware that many uniforming tools spec'd for a 0.062" hole actually cut oversize -- as much as .006-.007 oversize.

 

[Justin1098]

the sinclair decapping die comes with small pins.

 

[normmatzen]

Interesting, I just moved to 6BRX and bought two boxes of Lapua "Blue Box" cases. As I have a Lee universal de-capper, I carefully checked the decapping pin against the flash hole in the cases. It fit cleanly! I have never looked back.
My one indicator of no problem was the 5 ribbons I won at my last club meet!

 

[Killshot]

Simple: Get Redding's Universal decapping die with the BR/PPC-sized decapping pin.
This way it works for the small-hole cases as well as the standard.

 

[Killshot]

My one indicator of no problem was the 5 ribbons I won at my last club meet!

I'm sure you're very proud....and it was all due to those flash-holes.

 

[ridgeway]

the sinclair decapping die comes with small pins.

Yep...I use the Sinclair too. Very nice and works great. I've been using it for a couple years and never broke a pin. I know it came with extra pins, but who knows where I stowed them!

 

[Flouncer]

How do you measure with defining accuracy a 1.5 mm/0.059" diameter hole that is either recessed a couple of mm or at the end of a long 1.5-inch long dark tube ?????

I have at least 3 viable options:

Turn down the Lee Pins

Sinclair

Redding

Many thanks, as always, Arigato !!!

 

[infantrytrophy]

I have the Lee universal decapping die and have bought two extra decapping pins. Last year I called tech support at Lee and arranged to send my two extra decapping pins back to Lee. They were turned down to the correct diameter and returned at no charge. They now work great for decapping Lapua 6BR brass, as well as all my other brass.

Randy

 

[Forum Boss]

Two things:

1. The K&M Flash-hole uniformer (and some similar tools sold by other vendors) use a third-party sourced counter-sink bit. I do NOT like the countersink this tools cuts on the inside -- it is hard to do this consistently. Also, we found the bits vary all over the place. We had one that would cut a 0.068 hole, another an 0.064.

2. Regarding better accuracy with larger flash holes -- I can't comment on that -- it can be bullet/powder specific. However, we found that when we reamed 6mmBR cases to about 0.068 the PRESSURE INCREASED with same quantity of powder. Additionally, there is considerable anecdotal evidence that small flash hole brass can stand up to high pressures for more firings. If you really really feel the need to ream (against prevailing wisdom) I strongly advise against opening up your flash holes more than a couple thousandths.

So, again, my advice is LEAVE the FLASH HOLES ALONE, except for checking to see if there is a flake of brass. Remove that flake with a small pin vise bit. I do NOT recommend the tools that use a countersink in the inside because I've seen that people end up chamfering their cases inconsistently on the inside.

And to repeat, the bits on many of these tools are NOT consistent. The OD of the bit may vary from .063 to .068.

Primer DeCapping Pin Size
The last two Lee Universal decapping dies we had required turning down the pin. Pain in the *** really.

Redding 6mmBR dies SHOULD come with an 0.057 decapping pin. However, sometimes they ship with large pins. Redding can/will supply the small diameter pin if the die you receive has the wrong size.

 

[hogpatrol]

If one has access, the easiest way to reduce the pin size is with a cylindrical grinder. I use one that utilizes Hardinge 4C lathe collets. Chuck the entire decapping pin unit or just the pin. Leaves one end sized to fit the decapping pin and the rest of it, ground to suit. As an alternative, use a lathe with a die grinder clamped in a tool holder fixture.

 

[carlsbad]

Dang it. I ruined 4 pieces of brass before I decided the Lee decapper was dragging on something and looked up the size of the flash hole, finding this thread.

I like to deecap before cleaning the brass and use the Lee for 308. Guess I'll get out the redding and remove the neck bushing. Guess I should remove the expanding mandrel too. PITA.

Eventually I'll turn some lee pins down to .059 with my lathe toolpost grinder but it is a bit of work to set up and I have another job in the lathe tonight.

--Jerry

 

[DeltaBravo]

I use a DeWalt 1/16" drill bit, which mics out to 0.061, to clean out those chips that appear inside the primer hole in new Blue Box Lapua. I do all 100 cases, using my fingers as the "drill." For most cases, the drill bit just pushes through, some others actually need to have the drill bit twisted to remove whatever's in there.

I then use the K&M LARGE PRIMER REAMER to remove the flare on the inside of the case (verified by my Hawkeye); the large version doesn't get into the hole, it just touches the outer edges of the hole and puts a light chamfer on it.

Dennis