Got to thinking again 6BR vs 6ppc in slow powder

[82boy]

OK guys heres one for you. In a 6PPC when using a slower powder like H4895 great success has been reported by opening up the flash holes. This is a good combo, and has a few wins behind it. Why don't they use a magnum primer with the slower powder like the 6mm Br guys?

Now when shooting the 6mm Br, most times people load slower powders like Varget (Which is close in burn rate to H4895.) Why don't they open up the flash holes, like the PPC guys? Many have reported great success with 450 CCI magnum primers or the Remington 7 1/2 which my understanding is it is also a magnum primer, could this be to accommodate the small flash holes?

Am I missing something here?

[GaCop]

I'm somewhat new to 6mm BR shooting and anxiously await an answer too.

[82boy]

Wow, I am kind of surprised, 34 views and no answer.
Maybe I need to rephrase the question.

What is the theory of opening up the flash holes on a PPC when using H4895 powder, or what does this accomplish?
Why is not the same theory used on the BR cartridge? The two cartridges are similar in design, and close in case capacity.

[Eric in NC]

Can't answer you on the BR vs. PPC but with black powder cartridges you see guys using enlarged flash holes with pistol primers and guys using standard flash holes with magnum rifle primers - both seem to have good success (of course BP is the fastest of fast powders there is but a similar situation where there are two different ways of doing about the same thing).

[possum1]

Read's like no one know's or has any experiance on the subject. Why don't you do some testing and give us the feed-back.

[82boy]

Read's like no one know's or has any experiance on the subject. Why don't you do some testing and give us the feed-back.


O' am am going to try it out, but wanted to make sure someone else has not done it.

[82boy]

For the people that have an interest in this, I made a few calls to a couple of experts, Still no definitive answers. One told me that he has reamed the flash holes out on other rounds and have not seen a difference, and the other expert told me he never used the small flash holes in the first place, the first thing he does is open the flash holes up, and has done this for many years.

[possum1]

I know absolutely nothing about the BR caliber's, planning on changing that this year though. In my opinion a shooter try's something different and it work's for them, then they get into a habit of doing it i/e brass prep flash hole's and stuff. I've got a niche about turning every case in the holder 90* on every sizing and seating, just a habit I've got into and can't stop.

[trappst]

The technical term for this behavior is "Reloader's O.C.D."


;D

[possum1]

The technical term for this behavior is "Reloader's O.C.D."


;D
Reckon a fellar could draw a check for that ::)

[MZ5]

This is a very interesting question. There shouldn't be any reason in the world you'd need a magnum primer for a stick powder like a 4895 (nor Varget).

I think Eric is probably right re: 2 different approaches. As I understand it, the effect of opening up flash holes is to reduce the velocity of the hot priming mix particles whilst allowing a larger surface area of the powder to be exposed to them. A magnum primer may or may not do a similar thing. The difference between a regular and magnum primer can be that there's simply more of the standard priming mix in the cup. However, another way to make a magnum primer is to use a different mix/compound. See this rather wonderful article (http://www.shootingtimes.com/ammunition/ST_mamotaip_200909/index.html) written by Allan Jones, formerly of CCI/Speer/ATK.

So, to me, if there's something to be gained by increasing the exposure of a 4895 or Varget to additional ignited priming compound, I'd personally choose flash hole alteration rather than going the magnum primer route, if for no other reason than the fact that you can't be certain what you're getting if/when using a magnum primer. And, even if you do find out for one certain brand at any given time, it'll change on you later. I'm still a bit skeptical that those powders need additional primer exposure in those small cases, though. Looking forward to what you learn!

[MZ5]

I forgot to add that Federal uses a different type of priming compound than the rest of the industry. Their lead styphnate 'formula' results in more of the hot priming particles being generated at lower pressure over a longer period of time. This should result in the best ignition of the most different types of powder under the widest range of conditions, whilst having the lowest impact (increase) on chamber pressures.