I am trying to estimate the pressure of my 35 Whelen load. I am using 56.5 gr of imr 4064 with a 250gr swift a-frame bullet remington case and cci 250 primers, COL is 3.342. The accuracy is good with no pressure signs. I am planing on using this load for my trip to Africa next year.

thanks, Craven

62229 PSI
2584 FPS
3707 FT LBS

And a RED notation: "DANGER: This load exceeds maximum average pressure! !DO NOT USE THIS LOAD!

Steve does quick load alow for type of firearm to be input.
Craven

Loadtech gives even higher pressure.

quote:

Originally posted by craven:
Steve does quick load alow for type of firearm to be input.
Craven

I'm not Steve but QL goes by SAAMI guidelines for pressure. You can customize things like case capacity and bore dimensions. QL is pretty good but still just an estimate. It has no way to account for the primer, for example. In a recent article in Handloader, Barseness cited data showing that just changing primers can cause a 10,000 psi swing. Good article, by the way.

Steve wouldn't a long throat lower pressure in the chamber.

Craven

I'm still not Steve , but a long throat affects 1) the COL, which is already taken into account and 2) the QL start pressure, which is not exact or predictable.

What kind of velocity are you getting and from what barrel length?

quote:

Originally posted by craven:
Steve wouldn't a long throat lower pressure in the chamber.

Craven

Shade of Roy Weatherby!

That was his whole basis for his line of cartridges...fill the case with a ton of powder and then give the chamber a 6-mile throat.

In general terms, a long throat has pretty much the same effect as increasing the case capacity of the case.

It's not quite linear, but a pretty close approximation. FWIW, Dutch.

Popenmann, Im shooting a Remington classic 700 with a 22" tube I have not been able to chrono this load yet but I was after accuracy first speed second.
Craven

Load from a Disk gave results as:

58.2 grains is 95% load density

gives 2412 fps at 49,995 CUP

Over pressure does not happen until you load 100% case capacity, which gives 55,416 CUP at 2541fps.

But this program recommends as optimal:

54.3 grains is 88.6% load density at 2250fps and 43,482 CUP

Craven,
What I was getting at is that a chronograph would provide a sanity check. By all accounts, you shouldn't be getting more than 2400 fps, maybe 2450 tops, at sane pressures. A long throat will not change that appreciably.