Tips on fine tuning the primer seating process on Dillon 550

Gregor.Samsa

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May 4, 2019
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I finally got all supplies and equipment required to load bulk 223 on my Dillon 550. Overall it went well but wound up having som hiccups with the primer seater. The primer alignment seemed to be off every so often or the sliding mechanism would stick. I only loaded 50 rounds to test and took my time. A few primers alignment seemed slightly canted etc. I used the rcbs swaying die which in a few cases needed further reaming as it Didn’t completely swags the crimp. I’m. It blaming the equipment. I’m sure it’s me setting it up. Just looking for tips from those who have experience. Thanks
 

TheOfficeT-Rex

Not a good shottist
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  • May 19, 2019
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    For the sticky slider, try using some powdered graphite on the sliding bits. I prefer to cut the crimps instead of swaging them. I find the brass has a big impact on priming when using the dillon, but it usually does pretty well. Make sure you have the right tension on the shellholder plate. I make sure I bottom out the push stroke every time.
     

    Gregor.Samsa

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    Thank you. Points taken. I think I’ll cut the crimp next time as about 1 out if 5 needed some touch up with my chamfer tool.
     

    Gustav7

    Son of a Gun...
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  • Jul 18, 2019
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    Another fan of cutting the crimp.

    Take apart the slide mechanism and clean it well, get it completely dry and don't put wet lube on it. A little graphite like mentioned will work well.

    Make sure you get the primer cup on the primer seating stem straight. What I might recommend doing is aligning your whole press if it feels wonky, then align and install the primer cup on the press as you're using it. If you can't do that, then make sure you double it check it. It took me a couple tries on the screw that goes into the primer cup to get it aligned better.

    Sometimes the primer return rod (the long piece thats bent twice that rides on the little pulley wheels). You can slightly bend these one way or another to give you more pull or push so your slide doesn't stick as much and you get a more affirmative movement.

    Feel is another thing here too, is getting your press movement down consistently and priming consistently round to round. I'd say 95-98% of all my rounds, I can get the primers seated to within +/- 0.001" ... Thats good enough for me and I don't think I could get any better than that without something like a CPS.
     
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    Gustav7

    Son of a Gun...
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  • Jul 18, 2019
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    Keep in mind, the Dillon has a lot more working components and with that, theres screws to come loose and things that bend, or get out of shape.

    If something comes loose and you tighten it and then the primer cup is hitting the sides of the shellplate or its sticking more, you can always loosen things up again, align it real quick and tighten back down. It took me a few loading sessions to figure out the primer systems groove.

    Don't forget to properly lubricate the whole press as well. When I first put together my press i used a random lube and it worked, I cleaned it after like 1000 rounds and used a different lube and it made a huge difference (negatively). It really threw off my consistency, and I ended up cleaning the whole thing again and using a better lube. I use Butchs Gun oil on the main shaft and its legit like glass now. Dillon recommends a thin motor oil I believe.

    Good luck, the 550 is awesome
     
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    docohm

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    Aug 18, 2019
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    Primer slide sticking? What I've found with mine is to clean it VERY well with alcohol. Clean every surface that rubs. I also had to spread the sides of the holder just a tiny bit to let the bar slide better. I then run it dry. No lube of any kind. Works fine.
     
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    n0glock

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    Jun 18, 2020
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    I took the primer bar and polised it with a Q -tip with metal polish (that helped allot). I also went to the UniqueTek bearing plate for the 550. Be careful not to over tighten the bolts holding the primer assembly. The final advise I have is make sure the small primer bar and feed tube are installed. When I got my newer 550 it had the small primer bar on the press and the large feed tube installed. It kept flipping the occasional primer upside down.
     
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    Gustav7

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  • Jul 18, 2019
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    I also completely forgot to say I put the Primer Track Bearing on mine as well from Uniquetek, and really like that addition... Sort of forgot I had it on there lol
     

    Kyskeet

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    Feb 22, 2017
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    Another fan of the plate with bearing, not a stuck slide sence installing
     

    Dai Bando

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    Make sure the paper clip looking wire that holds the case is actually touching the case.

    Pretty important.
     
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    Gregor.Samsa

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    Make sure the paper clip looking wire that holds the case is actually touching the case.

    Pretty important.
    You might be on to something. I adjusted some clearance so I could get the casings in easier without interference. Thanks
     

    OLD308

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    Jun 8, 2018
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    Uniquetec has the answerers to your issues. And cutting out the crimps. I use a primer pocket uniformed.
     

    6.5SH

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    Jul 24, 2020
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    I prefer this bearing plate a bit more, but either extended one works.

    One other tip besides keeping the slide and bearing surface clean and aligned is do not excessively tighten the primer system bolts. You can go too tight even with hand pressure. Hold on to the short end of the allen wrench to limit the amount of torque applied.
     
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    milanuk

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  • Mar 23, 2002
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    Late to the party, but those primer slide bars were the answer to getting my 550 to where it was finally usable.

    I'd had some intermittent issues early on, and Dillon wanted me to box up the whole damn unit and ship it back, claimed they'd never heard of the primer bar hanging up and then snapping forward. I like my blue presses, but I call B.S. on that one. Not something that should require shipping back to the factory to sleuth out, either.

    Turned out the problem was two-fold. One, was operator error - I'd over-tightened the two bolts holding the primer tube assembly in place. It doesn't take much, but the inner wall of that lower housing is where the threads are - and it's *very* thin, and deforms easily. A couple licks with a small mill file fixed that up. The other... was inherent to the design of the primer slide, and the way the spring pulls *down* slightly as well as back when the slide is fully extended.

    Fixing the housing took it from about 50% reliable operation, to maybe 95%. That primer slide extension made it so I no longer dreaded using the dang thing.