30 degree vs 40 degree shoulder??

[mk443]

I ordered a 6mm barrel and an action with full intentions of building a 243 Ackley. I see a large amount of shooters switching to the creedmoor and 6xc with the 30 degree shoulder. I reached the XC pretty extensively and I'm still leaning towards the Ackley fully and I'm curious why (besides some claims of feeding) the creedmoor is so much more popular then the 243 Ackley in the custom world. Is barrel life that much better than a 40 degree Ackley? If so how/why if the are run at the same pressure point.

 

[adam32]

It's not that it's that much "better" or more popular, but the Creed doesn't need to be fireformed like the Ackley. I would take an Ackley anyday of the week over any Creedmore.

Barrel life is a relative term, load an Ackley to PPC levels and it'll have amazing barrel life too.

 

[just country]

morning, I have 223AI, 22-250AI, 243AI, 6mmAI. the maintenance of the casings
is minimal. I neck size only, trim when needed. very reliable case life.
the 6.5 creedmore is to me a wildcat caliber. some persons swear by this
casing modification. used for long range match shooting. to me the 260AI
would b a much favorable casing. my opinion. TUM

 

[MudRunner2005]

Another reason the Creedmoor cartridges are more popular, is because a major ammo manufacturer (Hornady) got behind them and started producing factory match ammo. If someone had done the same to the AI cartridges, they would have take off more, and been more popular.

I prefer the AI, and I prefer the 40º shoulder.

 

[Mikecr]

I don't actually like a 30deg shoulder, other than it's slightly better than a 20deg shoulder. 40 is the point where things get a lot better.
If your action is single shot/setup right for .473 casehead cartridges, the shoulder could be 60deg without detriment to feeding.