I use a Dillon RL550B and just noticed that my primers are not seating quite deep enough as measured by an RCBS primer seating depth guage. Aparently it has been like this for some time, I got suspicious & bought the gage recently. I have had no trouble with firing out of battery, but from what I hear, it is not something to trifle with. I have stopped shooting my reloads until I decide the danger. I am working on why this is happening ( been all through Dillon's troubleshooting section on the problem ) Anyone have any input, Ideas, or opinions on the problem or the subject of (slightly) shallow primer seating?

I think we need more information in order to solve this problem.

Are you loading for rifle or pistol?

If you look at a batch of primed cases all at once, do they all look the same, or is there a visible variation in the way the primers are seated? A visible variation is a signal that something is amiss.

Are your primers protruding beyond the rim of the case, or are they slightly under the case head? In other words, if you rest primed rounds on their heads on a flat surface, do the primers touch the flat surface, or is there a space, however slight, between the primer and that surface? If the primers are slightly above that surface, meaning that the head of the case rests on the surface, but not the primer, then the primer is probably seated deeply enough for the loaded rounds to be safe.

If you take a primed round and put it in a press and push on the primer with the press's priming arm, does the primer seat any deeper? If it does, this is a signal that your priming system is not seating them deep enough.

Another possible problem is your cases. Are the primer pockets in the cases at the proper depth, or are the cases defective in having too shallow a primer pocket? Have you checked different brands of cases to see whether there is any difference in the results from them? If you find significantly different results, this is probably a signal that the cases in which the primers do not seat deeply enough are defective in that their primer pockets are not deep enough.

If the cases are defective, then you may be able to correct them by using a primer pocket reamer on them. In any event, I recommend using the Lee primer pocket cleaner on all cases between the decapping and the repriming stage.

[This message has been edited by LE270 (edited 12-26-2001).]

I have only heard of firing out of battery on semi-autos. What are you loading for?

If it is a bolt gun I would go ahead and shoot them, and fix the problem before the next reload. Get a primer-pocket uniformer/reamer from any maker to solve the problem. I got one that fits my drill, so it's quick and painless.

If using an autoloader or pump think twice before shooting them. If they are within .005 of casehead I would personally shoot them even in my M1A - just not in a match!

Don