The NRA has been going around with their Labradar, checking velocities and pulling apart cartridges at Bisley. Not frequent but it does happen and has happened to two of my fellow club members.
I was party to a conversation that included an experienced competitive shooter, his assertion was the max load given in the manufacturers' load tables was his start point in load development. Similarly, I was discussing blow by in my .303, which I blamed on loose chambering, the chap I was talking to from a well-known gunsmith asked what load I was using, I said the max in the Viht tables 38.4gr, he said Viht were very conservative and I should add in half a grain so the case really expands and seals. I didn't, I stuck with the max published load and sent some cases to be annealed, which did help. I'm not saying it was bad advice, but it was anecdotal and not auditable and not something I could use in my defence if I had an accident.
I'm guessing that accidents happen for two reasons, one is deliberately loading hot for performance, the other is making a mistake due to a lack of understanding. I'm guessing the former is more likely with top-end target shooters and the latter for the rest of us.
Going back to the training course, a couple of bits of advice stick out, don't use Amrikan load data, we have a system of proofing in this country which they don't have. Their approach may include looking for pressure signs and backing off, we should never get near having pressure signs on the case. Then understand what you are doing, case thickness and thus capacity makes a big difference, use a load which nearly fills a case so it's obvious if you double fill, weigh all the completed cases, anything 20+gr out has got no powder and will be a squib, bullet seating depth also make a difference use the published COL. The load tables from manufacturers take all this into account and give a safe load.
I was simulating loads in GRT and taking the default .223 case volume of 31gr and then putting in my actual case volume of 30gr, the peak pressure difference with the same load was 9.3%.
I remain against compulsion but I don't know where you learn all of this without training.
Next move of the NRA ban home loads as unsafe with the goal to sell more ammunition.
I hope not it would cut the amount I shoot in half or push me away from my service rifles towards a .223, however, I can see them requiring training in the near future, after all, we live in a culture where there is zero-tolerance for risk and while shooting is an incredibly safe sport, probably the safest in the country, the perception of it is that it is dangerous.