Any way to test primer power/efficiency?

[watermonger]

I have these LR primers pulled from some German dm28a2 7.62x51 blanks. Is there any way I can test them to see how they perform compared to standard LR primers that doesn't involve loading live rounds? How much difference can a primer make in chamber pressure, is it safe to just blindly use unknown primers?

 

[troy fairweather]

Should drop a grain of two on the load and work up, they maybe corrosive I'd be more worried about that.

 

[watermonger]

Should drop a grain of two on the load and work up, they maybe corrosive I'd be more worried about that.

Unlikely to be corrosive considering the date of mfg and the country of origin, but I'll be thorough when cleaning after shooting with these. As for working up a load, AFAIK pressure signs are not a reliable indicator of excessive pressure in straight walled pistol cartridges. Could I load a few squib rounds of these and standard LRP's and then measure the depth bullet is driven into the barrel by each primer type? Or are primers to inconsistent for that to be a reliable method of estimating primer power?

 

[Blue68f100]

From my limited experience a primer will not move the bullet into the lands on a rifle round, too much case volume to generate the pressure needed. I way work for pistol but not a reliable way to do it. The only way I know would be to load up a round or 2 and shoot them over a crony, then use a known good primer. Min load. But even doing that many loads to not preform consistent at the low end.

 

[WeekendReloader]

Only way to tell is to load up a few test rounds. Drop the powder charge a bit and test. I highly doubt these primers are very much more powerful than standard primers. There is only so much room in side them to fill with primer compound material.

The question I ask is about the primer cup. Is it thick like a rifle primer?

I saw those training blanks for sale online. I wondered if anyone would buy them and pull the primers.