Originally Posted by PreciousLiberty
Originally Posted by PJGunner
Originally Posted by Yondering
What is all this about Whelen +P loads? +P is a SAAMI standard for certain cartridges, and does not exist for the Whelen. Whelen loads are either full power, too hot, or something less.

Well SAAMI standard for the .35 Whelen is a bit on the puny side thanks to Remington screwing up once more. Those of us who do load the Whelen for top performance should be able to call them Plus P or whatever the hell else they want. If my 225 gr. TSX load at 2710 FPS MV isn't a plus P load, what else would I call it? It kills elk very dead, is safe in my rifle so I guess I'll just consider it a Plul P load.
Paul B.

About that...I've had a heck of a time finding the current SAAMI 35 Whelen pressure spec. Sorry it's taken so long to respond.

However, with some inspired searching this morning I hit pay dirt!

https://saami.org/wp-content/upload...CFR-Approved-2015-12-14-Posting-Copy.pdf

Right from the horses mouth! It lists a Maximum Average Pressure (MAP) of 52,000 CUP (more on that below). It also helpfully lists some representative velocities of:
Code
SAAMI 35 Whelen Estimated Velocities

Bullet
Weight    Velocity
------    --------
180 gr    2,900 FPS
200 gr    2,660 FPS
250 gr    2,385 FPS

So, given that SAAMI expects a 200 gr bullet to run at 2,660 FPS versus 2,900, and the 250 gr bullet to run at under 2,400 FPS instead of 2,700, it looks like the "hot" Whelen loads are well above SAAMI spec. I'd say "+P" is entirely apt for those hot loads, whether or not SAAMI is abdicating whatever responsibility it has for that term. It also seems to me the only saving grace for Whelen pump and autoloader owners is that they must generally be knowledgeable shooters, given some of the hot loads available.

Now back to that MAP pressure in CUP. What in the world is CUP doing in any current pressure specification? It's simply outdated. IMO the industry should bulk convert legacy data from CUP to PSI in a safe way, and exactly zero new anything should be published in CUP.

Here's a good link on CUP versus PSI:
http://bulletin.accurateshooter.com...the-difference-in-pressure-measurements/

As that article says, the CUP number doesn't correlate well with PSI for several well known cartridges. The .223 is listed as 52,000 CUP and 55,000 PSI. The .308 is listed as 52,000 CUP and 62,000 PSI. So what does 52,000 CUP mean for the 35 Whelen? Apparently under 60K PSI. Perhaps a Quickload owner could guesstimate pressure in PSI based on the SAAMI estimated velocities and a 24 inch barrel...?

The other thing that surprised me is the amount of load data published with no pressure data. Nosler, for instance, doesn't include pressure data. I guess given the decent interior ballistics software around today one could double check that way...

I hope it was interesting!

Precious Liberty
All that may be true and correct with the powders that were available at the time of testing by SAAMI BUT Duluth the advent of newer and better powders surely this is now not as current as it could be.

SAAMI lists the 200 grain bullet at 2,660 fps for max pressure loads.
If this is correct how do Hornaday get 2,900 fps for the same weights and still remain within the saami pressure constraints.

I don't think companies like Speer, Nosler, Barnes or Hornaday would list way over pressure loads to obtain the velocities they get. If'n they were dangerous they would have had their respective arses sued off by now.
I'm not saying saami is wrong just needs revision.
Yes trying to convert cup to psi is a minefield frought with danger. Choose one or the other not both.
Just my 2cents worth from a humble Australian reloader.
Bob Nelson