Magic Creedmoor Powder

[darkker]

He is not using a Creedmoor but a 47 lapua that has even less case volume.
Is that with a 26" or with a 24? It says it is a Ruger Predator 6.5 Creedmoor 24".
Any ways thanks for posting that.


Quote by Darkker "And just as I posted in my debunking of the garbage claims of the FL bullets"
Were is this?

Sorry, good catch; confused rifles... Yes, that is a 24" barrel on a factory Predator. My 26" barrel is within 15fps at the same pressure interestingly enough.

Can't find it in the search, so apparently I never posted here...

https://www.shootersforum.com/handlo...-part-one.html

https://www.shootersforum.com/handlo...e-episode.html

[Charlie98]

I've got a question about the 6.5CM and powder selection...

What's with the slow powders? (IMR4350/4451, H4831, et al)

I've loaded for .308/7.62 (IMR3031 through IMR4064) and smaller rounds, the only thing I have that uses something that slow (H4831) is .348WCF and the 250grn bullets. I started loading for a friend's RPR in 6.5CM, thinking a 142grn bullet = IMR4895 or 4064, which you can use, but like this thread suggests... everyone is getting fantastic results with the much slower powder. I must admit, I was quite surprised.... and am sort of scratching my head as to why.

[darkker]

So there is quite a lot to that question, but here are the highlights for you.

"Burning rates" aren't a fixed thing, they change based upon the cartridge used in. Burning rate charts are a relative thing based upon caloric bomb testing.
Because burning rates shift, it isn't just the total case capacity that is important. For a very very generalized idea, think of it based upon amount of powder loaded for the bore and bearing surface of the bullet used.
The Creedmoor then looks stunningly similar to the 30-06, which is why the same powders are the appropriate choices.

[Charlie98]

So there is quite a lot to that question, but here are the highlights for you.

"Burning rates" aren't a fixed thing, they change based upon the cartridge used in. Burning rate charts are a relative thing based upon caloric bomb testing.
Because burning rates shift, it isn't just the total case capacity that is important. For a very very generalized idea, think of it based upon amount of powder loaded for the bore and bearing surface of the bullet used.
The Creedmoor then looks stunningly similar to the 30-06, which is why the same powders are the appropriate choices.

I assumed it had something to do with the bore/case (capacity)/bullet weight formula... I hadn't thought about bearing surface of the bullet. Interesting.