Pressure signs on steel berdan primed cases?
- Thread starter steelgray
- Start date
Brassman66
CGN frequent flyer
First sign of overpressure on Rifles I found is shown by the Primer, next stage is difficulty opening the Bolt !
Cheers
I don't think berdan primers show pressure by going flat in the same way as the boxer ones. If they do, it takes WAY more pressure for them to flatten.
They reload quite well and easily, if you have the proper primers for them.
There was a time, when the only cases you could get for the 7.62x54R, 7.62x39 and 8x57 Mauser were steel cased and if you wanted to get away from corrosive components, they needed to be hand loaded.
I have no idea of how they would handle hotter than issue loads but I believe most, if not all, "Blue Pill" rounds used to check new rifles for pressure concerns are made from steel cases. Please correct me if I'm wrong on this.
I've reloaded steel cases up to ten times without issues for both the 7.62x39 and the 7.62x54R.
My loads and consequent pressures were very similar to specified issue loads with the bullet weights used.
I will admit, the steel cases seem to require "softening" after the third reload and they definitely require good lubrication when resizing.
I was also careful to use the same cases in the same rifles and not interchange them. They were only neck resized after once firing.
I couldn't get away with just neck resizing the 7.62x39 for the SKS and bolt action rifles weren't available while I was reloading the steel cases.
If the cases were lacquered, not all were, they could/did leave some residue behind in the sizing die, which would build up, if a lot of lube wasn't used.
That could be because they seem to be harder, closer to milspec than North American commercial primers??????
This is the best indicator of pressures when the components are known.
Some of the new "light magnum" propellants will give high velocities without the same pressure spikes but tend to lengthen the spike for another couple of nanoseconds to achieve the higher velocities. These propellants aren't usually available for hand loaders.
- Location
- Nova Scotia
I think someone that does testing, and argues for pages to which is more inferior brass, could research pressure signs. Something most reloaders research.
Get a reloading manual and stay -below-published load. Steel case - military case have less capacity than commercial brass case. A chrono is a good help in load development - stopping putting powder in, when published velocity is reached.
When you see pressure sign you are already over pressure. Flattened primer are usually a first indication but there is also other factors that can cause flattened primer. Cratering is another sign of over pressure but when you deal with old military style gun..not always.
Steel case were not made to be reloadable. Some do, but expect neck and body split - crack in a short time. They are a killer on sizing die if you reload a good amount of it. Get a stuck case removal kit-tool. It can became handy.
Last edited:
- Location
- Western Manitoba
Was an article by John Barsness some years ago - was likely in Handloader Magazine and in at least one of his books - he "worked up" several hand-loads for several of his rifles - one that he had been using at least 15 (?) years - took all to Western Powders lab in Miles City, Montana - had them pressure tested on their machines - his conclusion was that most "home done" pressure testing is NOT dependable - sometimes works, but he has examples of each NOT working - primer condition, case head expansion, bolt lift - as I recall - but, he found 100% alignment between muzzle velocity and pressure - to the extent he said that a reloader CAN NOT get more velocity without also getting more pressure compared to pressure tested data in manuals. So, if a pressure tested load in a manual uses XYZ powder in a 22" barrel and gets ABC velocity - if you get MORE velocity, then you did that with MORE pressure - regardless of the actual grains of that powder that you used with that primer, that case, that rifle - despite presence or absence of "home done" signs. He says he has also done it the other way - if his velocity is LOWER than the manual (taking into account the barrel length) then he adds more powder until he is at velocity - important to note he compares to identical, or nearly identical powders. That load that he had been using for 15 years turned out to be well over SAAMI limits - meaning he was into his rifle's "safety factor" - that may or may not be of concern to some people.
That gets to be of concern if you load for the 7x61 S&H cartridge - Norma made TWO versions - at least 5% or 10% capacity difference between the two - if you can not be bothered to look at each individual head stamp, you may end up with a load for the roomier case, in a small volume case. The two cases are identical size on the outside - use same re-sizing tools, fired in the same chamber - same pressure limits. One will have head stamp 7x61 S&H Re, and other will have head stamp 7x61 Super.
That gets to be of concern if you load for the 7x61 S&H cartridge - Norma made TWO versions - at least 5% or 10% capacity difference between the two - if you can not be bothered to look at each individual head stamp, you may end up with a load for the roomier case, in a small volume case. The two cases are identical size on the outside - use same re-sizing tools, fired in the same chamber - same pressure limits. One will have head stamp 7x61 S&H Re, and other will have head stamp 7x61 Super.
Last edited:
