Primers- How Interchangeable are they?

[lazyengineer]

To be perfectly honest, in my experience - a lot more interchangeable than people act. It's on the mild end of a load, is where I personally see the difference. where a difficult to light ball powder in a mild charge is being lit by a mild primer vs a hot primer, where differences can get profound. With normal and hot loads, I tend not to notice primer really having any effect at all - personally. With the main item there being some primers are more prone to mechanical failures like piercing, on the hot end, than others; but otherwise not really affecting velocity, performance, pressure sign etc. Look forward to what some others say - some folks here have done quite a bit of work on the topic, and even wrote reloading manuals - so that's pretty impressive.