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Armbrust on primer substitution
http://www.armbrust.acf2.org/primersubs.htm
The greatest he documented was 2800 psi

Interestingly increasing crimp depth on one load increased pressure 3800 psi

Glad you asked Mr. House.

It was Randy Wakeman (my bad) and his contact at Accurate Powders/Western Powders that suggested a 5000psi pressure change merely from a primer substitution:

https://www.randywakeman.com/shotgun_pressures.htm

Take it up with him.

Best,
Ted

I would think that the reason for pressure spikes due to primer substitution would be caused by going from a primer of lower brisance to one of higher brisance. I cannot fathom it working the other way, but I could certainly be wrong.

I have substituted Cheddite primers for WW or Rem., had the loads tested, and found no pressure increases from the loading manual's stated pressures for the same load with another primer. I believe Cheddites are placed lower on the brisance chart than several others, but I'm going off of memory here. I've got a copy of that chart somewhere out in my loading room.

To achieve maximum velocities steel shot recipes called for the Federal 209A primer. The hottest out there.
Many of these loads are at SAAMI max for gauge.

Mr Schefelbein
I made the effort to find and share Armbrust's blog, which provided numbers, which are good.
It was not intended to be a personal attack, and I'm not sure why you viewed it as an affront.
I've had plenty of debates with Randy on the Shotgun World site.
He made a claim "someone told me", of which one may be skeptical, but with which one can't argue.

May you and your family experience God's peace and joy in the New Year.
Drew

Unfortunately, Dr. Drew, I’m not sure I believe the industry has a vested interest in people being able to reload their own ammunition. Further, getting exact answers on specifications on the ammunition they produce is near impossible. We don’t know, what we don’t know.
Except, that, mostly, usually, we think, sometimes, the store bought stuff will be under SAAMI max.

Kinda.

That is literally where we are.

I wish the exact same sentiments to you and yours. Further, I sincerely hope you don’t end up with a component that alters your hand loads to the tune of 2500-5000psi.

Because, they are out there.

Best,
Ted

I don’t chase people around the internet just to argue.
I have very carefully and very precisely, reloaded 10’s of thousands of shotgun cartridges.

For modern fluid steel barrels:

I read the powder manufacturer’s recipes. I follow them.

I rely on the data provided from the powder manufacturer to be accurate.
If they are releasing inaccurate information to the general public, they are assuming all of the risk for the consequences.

You can do this because:

there are very few variables in the cartridge remanufacturing equation.

Not every variable is of the same consequence.

The big four elements are the dominant terms in the equation, the rest are essentially noise.

For the tiny quantity most sxs owners fire, I think they are better served buying from RST.

Over time, it became clear that anything connected to a trap shooting site was unsafe garbage.

Why people do what they do continues to be a sad mystery to me.


Probably one of the great consequences with very positive results, was the consolidation of the powder industry, and the Covid manufacturing disruption on the plastic side.

3/4 of all the crap out there that people were dangerously assembling is gone from the market.
All that orphan reloading debris that people hoard can go right into the dumpster.

So the remaining items Are much safer to use, because there are fewer combinations of stupidity available.

This ain’t an argument. I’ve been in an argument or two. The last really good one I was in I got knifed at the Broken Spoke bar in Rice Lake WI. I wasn’t much help at the hospital when the cop asked me what he was wearing. “A cowboy hat”, says me. The cop says “The only people for sure not wearing cowboy hats were the two guys you went with, me, and the lady tending the bar”.

That should have been a hint earlier in the evening, I guess, but, I digress.

Short of pressure testing every single batch you load, and testing every time you get a different lot of primers, powder, hulls, or wads, I don’t think you can know accurate pressure numbers.

You can guess, which, is what you are doing, no matter what you believe.

Good luck. I mean that.

Best,
Ted

If the manufacturer of the powder publishes their numbers using the same components as I, my expectation is a similar outcome.

I run my loads across a chrono, and get very small sd’s.
So I know I’m precise in my practices.

I trust the powder manufacturers research on pressure.
It’s just up to me to be consistent on my end.

Now that there are way fewer options out there, the process is actually easier.