I’m very diligent about checking for powder but 4.2 g in a 45 case isn’t much so I coulda had one look full and passed it
Just when (in the cycle) and how do you check for powder??
I know heavy bullets with fast powder is always more susceptible to this.
A 230gr isn't considered a heavy bullet in .45acp. Its the standard weight.
Loading on a LNL Progressive I assume during the process one was loaded light due to the standard hiccups that come with progressive presses.
I don't know the LNL system, so can't comment on it. But I will say that thinking there are "standard hiccups that come with progressive presses" concerns me a bit
If you are getting "hiccups" with a progressive press, you aren't doing something right. Either not having brass properly prepped or some kind of error or inconsistency in operation. Its easy to do, and often difficult to catch, until you try to chamber / shoot the bad round.
What you describe, bullet just barely into the barrel, is typical of a no powder squib. Several things are possible reasons, both mechanical malfunction and/or operator error.
I had a progressive once where sometimes the measure would "stick" in the up position. The case that pushed it up got powder, but with the measure sticking in the up position, the next case would not get powder, and to add to the issue, most of the time, when the ram came down so would the powder measure, giving a completely normal look, but a case with no powder. Also the next case, with the measure back in its proper position, got the normal powder charge.
The result was you could get one, or more rounds without powder in a batch, IF you didn't happen to notice the measure was stuck WHILE it was stuck, and IF you didn't visually (and properly) inspect each case for powder before a bullet went on it.
This, and some other issues is what lead me to abandoning progressive presses. I loaded more bad rounds (approx 3 ) on my progressive in two years than I had in the previous 20 years of loading on a single stage press.
OF course, part of the issue was me, but I've gone back to single stage presses, careful inspection of every round at every stage of the process, and for me, while it takes more time, I get better QC of the ammo I make. (or at least I think I do.
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