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Primer Seating Difficulty

I recently purchased and set up a 550.

When loading my first 200 rounds of 9mm I experienced a sporadic problem with primer seating. The old primer would be removed, however, once in a while the new primer would not properly seat. They never came out sideways or upside down, but would sometimes not be seated entirely in the casing. On other occasions (more frequently than the partial seatings) the primer simply did not seat whatsoever, which was discovered after the rest of the round development was completed.

I noticed that if I held the case in place as I was moving the operating handle forward to seat a new primer so it couldn't move at all, the new primer would seat soundly each time. My presumption is something in the primer seating system could use tightening or an adjustment. It did seem there wasn't much resistance, at least sometimes, as I moved the handle forward to seat the new primers. Without going through each of the possible primer seating fixes is there anything which sticks out for you, Dillon, or those of you with more experience at this than me?

Other than my periodic primer seating issue my first attempt at loading (ever) went just fine and turned out rounds which measured and seemed to function at least as well as the commercially purchased products I have remaining.

Thanks for the help!

Dave

At the first station there is an adjustable spring, closely resembling a bent paper clip. This spring should be adjusted to within .002-.003" of touching the rim of the case. It's function is to prevent the case from sliding out of alignment with the primer.

I thought that spring was in tight enough, but thanks for the advice. I'll give that a try and see what happens.

Dave

Dave,

 

You may well have tried this already, but I had a similar problem with my 550B.  I periodically tighten up the shell plate to leave it just loose enough to turn it easily.  I would also put a drop of oil where the shells fit and let it wick up under the shell plate to easy turning with close tolerances.

Another suggestion is to tighten up the primer column tube (with two hex screws underneath) with the primer carrier fitting in the hole under the shellplate to facilaitate the centering of the primer placement.

I hope this helps and is not too confusing.

 

Sniper48

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