actually the person involved mentions three plausible variables(and new primer 650 parts that came on the market within recent years, I own a recent 650 model).
Federal Primers, S&B brass (primer pocket too tight) and misalignment of the primer punch which seats the primer.
I've used thousands of federal primers on my 650 and I've primed thousands of S&B 9mm brass without any problems. That doesn't mean there isn't a problem just those components have not caused any detonations on my 650.
However, if you misalign the punch and try seat a primer at an angle each time you prime every piece of brass, to me it will happen sooner or later due to the misaligned angle of seating the primer.
The guy that had this primer detonation is no doubt more experienced than me....hell, he had already loaded 75,000 rounds on his 650 before this happened but just because it happens doesn't take anything away from a 650.
I must have read +90% of all posts regarding 650 primer detonations before buying a 650 ( I was fully aware of this concern and the related threads) - to summarise the variables involved or plausible reasons given by the person involved
- federal/winchester primers - too sensitive or brass issue like S&B tight primer pocket.
- press hadn't been regularly cleaned and primer compound and static electricity set things in motion (carpeted floor in a few of these)
- something wrong in the angle of seating the primer - misalignment of punch and crushed primer.
- working the machine too fast and forcing the lever unintentionally or forcing the lever intentionally (given slightly more tension than previous pull on the lever but the operator thinks it is nothing dramatic to investigate and decides to carry on regardless).
The above from recollection were the main themes running through these 650 primer detonation threads. I don't claim they are the reason for these 650 detonations( I don't accept the federal one personally). I also wouldn't claim the 650 is more prone to detonation than for example the LNL - to reach that conclusion you would need to have the total number of both machines in operation and the exact number of cases of detonation per machine....as a start to reach a conclusive & supported opinion.
If you have 10 times more 650s used in the US than (as an example of another progressive ) LNL and consequently more 'hits on the net' for a 650 primer detonation than a LNL, you cannot conclude that the 650 is more likely to detonate than a LNL. There are faults even in this simplistic approach to assess the safest progressive on the market. That information (on primer detonations) is held by the manufacturers and is unavailable to the public. Dillon recognises the 650 has more detonations than their other machines - not surprising given the layout of how primers are fed on the 550/1050 machines.
I regularly clean my 650 (and the primer tubes/pick-up tubes) every couple of thousand rounds, I'm conscious of static electricity given my personal set-up and am not aiming to break the Guinneas book of records in the number of loaded cartridges per hour - I work my 650 relatively slow in comparison to some numbers I read on here of 6-700/hour and have a slow tempo. That being said, I always very slightly pause before seating a primer and never force anything when I feel the required force on the lever is 'different' (which can range from a very slight increase in pressure to the lever won't physically move.)
'Maybe' it is only a matter of time before I have a primer detonation on my 650 and it is an inherently risky progressive press to work on. I'm confident I can get to the 75k mark and beyond without any incident(at least I hope) given the precautions I take.
I've probably jinxed myself is saying that though
Let's hope not.
