Is there a way to find pressures if the bullet manufacture does not list it? For instance, I want to keep pressures at maybe 45-46k CUP in my 358 Win. I was using Barnes data because I amusing Hammer bullets. Using IMR 4198 Barnes shows a start load of 40 grains for 2586 fps and a max of 44 grains for 2845 fps. Am assuming the max load is 50k+ CUP, but where would 46k be? In the middle?

You don't have enough information.

I'm interested in your motivation for loading to that particular pressure level. What's up?

Built Rifle off a small ring large thread Mauser. Was recommended that I keep the loads below the 50k cup level.

Look at Lyman and other reloading manuals with pressures. You should be able to find both cast and jacketed loads for IMR 4198 then you can get a rough approximation of the pressure range your looking for. Quick load can also give an approximate number but I don't have it.

You are playing Russian Roulette with a controlled explosion.

The serious issue is Original Heat treat combined with Work Hardening from years of use

Older Speer Manual has reduced load information.

Life is precious, handle with care..

The short answer is no. Anything you do is only an estimate unless you have the equipment to measure pressure. The only way to get close is measuring velocity but it's all a SWAG.

I think Quick Load gives pressure. I don't use it myself, but I believe I've heard that is true.

So you would say even mid level 358 win loads are dangerous?

It will deliver an educated, calculated guess and is often better than nothing at all if you're out in no-man's-land but it can be pretty misleading at times. Too many variables.

Hammer bullets are not in Quick Load, so I can't help you there.

Whoa there...I have no clue what a Hammer bullet is...no clue about weight...no clue on bearing surface. But in a conventional bullet...200 grain Silvertip with 40 grains of 4198 gave 2495 fps out of a 25" bbl at 52,000 CUP. This is from the IMR handloaders guide. A case full of 4064, 49 grs will give 2525fps at 46,200 CUP.

Hammer bullets are fairly new....lead free. They do have grooves cut into them somewhat like Barnes but different. It is supposed to reduce pressure. They are 178 grains so I was going off of Barnes data for 180 grain bullets.

What Keith is telling you is that without having actual data with a given case, primer, powder and bullet, You cannot even make a good guess. Guessing even when you have reason to believe you may be good at guessing is dumber than a box of rocks when it comes to loading, and doubly so when it comes to loading for known weak actions. REMEMBER even with a good pressure tested load you are still guessing about the pressure in YOUR rifle.

Star with getting SAAMI specs for max pressure for that rifle. That is what FACTORY ammo will be loaded to. If that is above 50k then you need to find a load recipe that has been pressure tested under 50k and follow it exactly. You do not want to do a high speed disassembly of a rifle with your face and hands in close proximity to it.

Jevyod...Who built this rifle for you? If built by a competent smith, he should be able to tell you if the build can take the pressure the 358 produces with no QUESING on your part. ASK the question..

Malcolm Ballistic Tooling. He said he woukd not drive the socks off it but would so a middle of the road load.

Why would they fit and chamber a barrel to an action unsuitable for factory ammunition in the chambered cartridge?

Why would anyone care how much pressure they're creating as long as it's not to much?

Of course you could always proof it. Load up a few max loads, tie it down, get a long string, get behind a barricade and pull the string.

Jevyod...Ask the smith to work up some loads for you. You`re concerned now, I assume with out having shot it, I`m thinking if you do load for it, each time you shoot, you`re going to wonder if it`s going to let go.

Well I was not initially concerned until someone else told me it was a small ring large thread mauser which supposedly is weaker than just a small ring. The gunsmith twsted it with loads 1 grain under max and I already fired it 40 times and some of those were max loads ( as per hornady manual) I am more worried about the long term affect of running full bore loads all the time

Because someone payed them money to do it.

Jevyod...Well then your answer is simple, back off max a grain or two as did the smith.
Don`t think the target will know.
Good Luck

Malcolm should share his M1A 358 Win loads with you. They are lower pressure loads that should work in your rifle too.

There's a member who sells alot of once-fired brass in the classifieds, crod1972. He pressure tests alot of ammo and could possibly give some advice based on his observations.

Thanks, Dinny

One thing about CUP, that does not equate nor does it corelate in any way to PSI. Case in point, 42,000 CUP in a 6.5x55 Swede is about 52,000 PSI, while 35,000 CUP in a .45-70 is about 35,000 PSI. It's for this reason that I wish they would drop CUP entirely.

Not so.

https://www.shootingsoftware.com/ftp/psicuparticle2.pdf