Having an issue with my Dillon 550

[bdb]

Just by way of background. I have about 20,000 rounds on my Dillon 550. I reload for 9mm and 45ACP and I would say it's about 80/20 in favor of 9mm. A while back I was having an issue with the small primer slide sticking in the upstroke and I would have to manually push it in to seat the next primer. Dillon sent me a while new primer feed assembly (the upright part that bolts on). It seemed to help for a while. I recently swapped out the lg primer slide after doing 45 and it was sticking again with the small primer. I ordered a new small primer slide and still have the issue.

I have run through all the basic troubleshooting and cleaned everything but the primer slide on the small primer still sticks for me. Any thoughts before I call Dillon and speak to someone? I feel like I have recently replaced both the major components. Any chance I tightened down the bolts on the primer feed assembly and it bulged out the base casing the small primer slide to stick? It didn't for the lg primer feed which is why I don't think that is the issue, along with I don't put that much force on the bolts while tightening.

Just looking for any wisdom here. Thanks.

 

[M1911]

Check the bearing plate below the primer slide. Did you clean that plate? You might want to just replace it by now. Also, try putting some graphite lubricant on top of the bearing plate.

 

[45BPCR]

I own a very "high mileage" Dillon 550.
Get this improvement.

https://www.amazon.com/JW-Systems-Dillon-Primer-Bearing/dp/B01L9Q2TX4

 

[bdb]

Check the bearing plate below the primer slide. Did you clean that plate? You might want to just replace it by now. Also, try putting some graphite lubricant on top of the bearing plate.

Yes, cleaned and also replaced that plate earlier.

I own a very "high mileage" Dillon 550.
Get this improvement.

Thanks, I'll check that out!!

It's just odd to me that with the large primer slide I have no issues but with the small it sticks and isn't clean. Everything else is the same. I literally finished 1000 .45's on the weekend and swapped out the lg for the sm primer slide and had issues. My brand new small primer slide showed up from Dillon yesterday and still sticks after putting it in and loading 20 rounds last night. I'll keep tinkering.

 

[M1911]

Let us know if you get it figured out. Or if you don't and what you tried.

 

[38ExtraSpecial]

Just by way of background. I have about 20,000 rounds on my Dillon 550. I reload for 9mm and 45ACP and I would say it's about 80/20 in favor of 9mm. A while back I was having an issue with the small primer slide sticking in the upstroke and I would have to manually push it in to seat the next primer. Dillon sent me a while new primer feed assembly (the upright part that bolts on). It seemed to help for a while. I recently swapped out the lg primer slide after doing 45 and it was sticking again with the small primer. I ordered a new small primer slide and still have the issue.

I have run through all the basic troubleshooting and cleaned everything but the primer slide on the small primer still sticks for me. Any thoughts before I call Dillon and speak to someone? I feel like I have recently replaced both the major components. Any chance I tightened down the bolts on the primer feed assembly and it bulged out the base casing the small primer slide to stick? It didn't for the lg primer feed which is why I don't think that is the issue, along with I don't put that much force on the bolts while tightening.

Just looking for any wisdom here. Thanks.

Does the primer slide stick in the rearward position while it’s picking up a new primer?

 

[bdb]

Does the primer slide stick in the rearward position while it’s picking up a new primer?

No, it comes back, picks up the primer, slides forward about 1/2 an inch on the upstroke and then sticks there and I give it a little tap on the back and it slides forward the rest of the way to the final resting position for seating the primer.

 

[Andy in NH]

I have had that same malfunction.

I purchased an aftermarket Bearing Plate and replaced the Primer Slide Return Spring.

I am also more proactive in keeping it clean now.

 

[Rugerfan]

My 550 is a high mileage unit as well. I had the same problem and could not get it to operate correctly after cleaning, polishing, lubricating, replacing, swearing, praying, voodoo, and using black magic.

I installed the bearing kit mentioned above and no more problems.

 

[EddieZoom]

....replaced the Primer Slide Return Spring.

My vote is this given your description of the issue...but I also have the aftermarket plate and consider it a worthwhile upgrade.

 

[38ExtraSpecial]

No, it comes back, picks up the primer, slides forward about 1/2 an inch on the upstroke and then sticks there and I give it a little tap on the back and it slides forward the rest of the way to the final resting position for seating the primer.

I’ll have to take a look at my press tomorrow morning. I have two extremely high mileage presses. I’ve never had an issue with a primer slide that didn’t equate to some sort of little adjustment.

Any chance you can get a picture of it while it’s stuck?

 

[45BPCR]

For my old 550, the stainless steel bearing plate fixed every primer bar sticking problem.
It's been Rainbows and Unicorns ever since.
For $30.00 it's a good improvement for any 550.

 

[bdb]

I'll buy the bearing plate mention above. I took it all apart last night, cleaned everything and it's running much better but still occasionally sticks. I'll see if the bearing plate solves my issue and may also replace the spring.

Thanks for all the feedback.

 

[Stape]

When I've had this problem on my 550, I of course clean everything, but additionally I'll polish the bottom contact areas of the primer arm that slides fore and aft. I'll use flitz metal polish. I'll do this maybe every 8k-10k rounds.

ETA: Sometimes the two screws holding the priming system are too tight, that'll cause mine to bind as well.

 

[Jay77]

Mine after I polished it. Same problem but it was better after the polish… now I clean the press when it starts to act up.

 

[livelyxp100]

Mine after I polished it. Same problem but it was better after the polish… now I clean the press when it starts to act up.

Over tightening the primer tube bolts will cause the side of the base to swell. Dress the bulge off and use a slide bearing also.

 

[bdb]

Well I bought the slide plate with the bearing. That actually made it worse. I did some testing and a good look at the parts. So the slide tube bar that screws in appears to be my issue. There is definitely bulging by the screws. I can feel the two bulges. I used black marker on it to see contact areas so I could see the contacts. This part is relatively new and I didnt think I tightened the screws down too tight. I can try and remove the bulges and polish I guess. May be time for a call to Dillon to discuss options. Last time they mailed me a new primer assembly no questions asked which is great but I am surprised it happened again. Here is a pic of it.

 

[bdb]

Well, since I have 2 of the primer tube assemblies one of them became a test bed. I lightly filed down the bulges at the screw locations, polished it up and now it slides perfectly with the regular slide plate and the bearing extended plate as well. Problem solved! Time for another 1000 9mm this week.

 

[38ExtraSpecial]

Well, since I have 2 of the primer tube assemblies one of them became a test bed. I lightly filed down the bulges at the screw locations, polished it up and now it slides perfectly with the regular slide plate and the bearing extended plate as well. Problem solved! Time for another 1000 9mm this week.

How was it damaged? Overtightened?
Could the be using thread forming taps and the metal is being displaced?

 

[pastera]

How was it damaged? Overtightened?
Could the be using thread forming taps and the metal is being displaced?

From the look I'd agree that it was at least partially manufacturing. I doubt those were threaded before the slot was machined and that inner wall is way to thin for anything but thread milling.

I'd just dress the damage with a fine file and be careful with the bolts - but reading the rest of the posts it seems cleaning up the slot with file was the solution.

 

[houdini]

Dillon have these plates to put under your primer, it made a lot of differents, clean it all the time that its on a 550 press.

 

[Mikie]

I had exactly the same problem and determined it was from over tightening the screws that hold the primer mechanism to the press. Over tightening caused a bulge that was binding the slide up. I solved it by using a honing stone to smooth out the bump and the problem was solved. I make a point of not over tightening those set screws.