Home Forums Hunting & Shooting Ask The Gunwriters Pressure Testing Labs?

Where would a reloader send some ammo for pressure testing?

I know the Western Powders lab in Miles City, Montana would pressure-test loads for a fee, since they did a lot of testing for various other companies. But that was before Hodgdon recently purchased them.

Thanks...I'll check with them.

For a few hundere d $$ , you can hve your own lab. Pressure Trace II

https://www.shootingsoftware.com/pressure.htm

Believe me, Pressure Trace is NOT the same as having pressures tested at a piezo-electronic lab. Have worked with both.

MD....

I have had considerably better luck than that.

I have a data set from Ken Oehler, where he instrumented a barrel with both piezoelectric and strain gauge systems. In the end, both data sets overlaid each other practically perfectly, indicating accuracy. For all my rifles, measured data comports very well with published data.

One thing that most people neglect is careful temperature control of the barrel and ammunition. If you do that, there is no reason that a strain gauge system cannot give you excellent results.

Also, because of the way Ken set up his test, we were able to calculate the precision of both systems. They are, for all practical purposes, equally precise. Which you use is a matter of convenience.

Thanks, Denton. It was not my Pressure Trace, and the owner was operating it--which might have been the problem.

However, I have also known professional labs that did not get "correct" results with strain-gauge systems, as in showing smaller cartridges getting more velocity than larger cartridges of the same caliber--at the same pressure. Obviously dunno what the problem was there.

Both systems have enough pitfalls to keep the user entertained.

Yep!

One of the keys to out sourcing analysis has always been, unless you are a major funding source, what level of precision can you expect?
Do you seek a number?
Or,
Do you seek to understand?
(Note: this position May be unpopular with fee for service laboratories.)

I'd love to see the data set, and learn about the setup. Can you share it?

Thanks,

Jason

Ken shared the data on condition that I not share it further, but did allow me to comment on it. At the time, he planned to include it in a book he was working on.

The test barrel was equipped with two piezo channels and two strain channels and data covered a wide range of pressures.

Anyone else remember (anyone ever use) the York-Cantrell system?

Then there was this system. It consisted of a steel tube with a sliding mass inside. It mounted in the rifle's scope rings. A lead slug was placed in front of the sliding mass, and recoil deformed it. Like the CUP system, you inferred pressure from deformation.