Walnut

Long time lurker, but I have been running Scheel buffer in my carbine for a couple of years now and really like it, I use it for a training replacement for my 5.56 AR since I can't do drills with rifle calibers at the range I belong to. I ended up getting rid of the supplied spring because it wouldn't always feed from bolt lock back. 6 months ago, I just cut down a AR 5.56mm carbine factory spring. I just measured the number of coils so the buffer would bottom out in the stock and not have spring bind when at full compression. Works much better and still super soft shooting. I had to play with my roller spring weights to find the happy place. I am running a old school extractor CMMG BCG and an colt style lower receiver. This spring I bought at a5 buffer tube from scheels, put my wave washer in the butt with a couple of quarters to separate the carbine spring and buffer. Now it is really soft and fast. I am a weirdo, I like heavy 9mm for everything, so my current load is 165gr Powder Coated RN, 1.150", 2.5 gr Tightgroup 129 pf in 16" Good luck!

I had the exact problem with Hornady brass, so I bought a RCBS Small base Die and still had cases that wouldn't drop gauge in the Hornady gauge periodically. I sent it back to Hornady with my Hornady 6.5 Creedmoor standard sizing die with some "bad" brass and I got a note back that they were all in spec. Later I bought a 6.5 Creedmoor drop gauge off eBay from The Shooter Box, checked the "bad" brass with the new gauge and a new AR10 Shilen Barrel, Short answer all the "bad" brass drop right into the barrel and the new drop gauge. I have bought several of their case gauges, I really like them! Sometime soon, I am going to do a chamber cast of the Hornady drop gauge and see what the specs are on it. I suspect that it is under sized or cut to SAAMI min specs

One other issue to look at is the op-rod itself. The op-rod is a wear item just like the orifices, springs etc. Call up Dillon and request couple extra op-rods and keep one as a master to compare against your active rod that is on the machine. I have bent them in the past to make them work, but I find it's just a temporary fix.

On a similar topic, I have been shooting and carrying Sig V-Crown 125 gr factory ammo for my 5" Super. The factory load chrono's at 1247 fps avg of 15 rounds fired @ 15 feet. Went home pulled a bullet looked at the powder, looked just like Power Pistol, weight 5 factory rounds avg was 6.7gr. Called Sierra for load data on the bullet (they make the bullet for Sig) and the max load for Power Pistol is 7.8gr which is well above 6.7gr. Loaded 5.7gr with a some V-crown bullets I bought at the gunshop and shot them. 15 rounds avg 1245 fps @ 15 feet which I would say is pretty darn close.

After reading all the post, my first thought is check 13887 Operating Rod Bracket and see if it is twisted slightly. The op rod should be 90 degrees from the press and not move back and forth at an angle. I check it by pulling the primer slide all the way out without the spring connected and look at the relationship of the rod as it engages the roller on the side of the primer slide. It should go back and forth parallel to the travel of the primer slide. Set Op rod bracket .015" off the top of the press (don't touch it) and run primers though as you cycle the handle back and forth. if it binds, twist it counter or clock wise no more than 1/16 of a turn a time. A little goes a long ways. Hope that helps, Jeff

I love that powder. 23.9gr under 55gr Horn FMJBT with a CCI primer, Lee crimp die @2967 fps out of 16" Not the fastest, but will hold 1/2" out of my AR all day long.

Many people love to suck down the two 5/32 screws and cause the bulging issue. I have fixed the display 550 at a Dillon dealer with that very issue. I tell fellow 550 users to hand tighten, then use the Allen wrench to turn it no more than 1/16 of an turn, just to bump the threads down. I have taken my torque wrench, 5 INCH pounds is sufficient.

Nice primer upgrades. I love IT! JW

Woops, I was a bit slow, Chills1994 got it perfect!

I have had a similar issue happen to me, the primer chute was opening and closing like it should, but primer were going all over the place too. I was using RCBS dies, so I figured out the decapping pin was my issue. I played around with the length first and then changed the tip of the pin to look like a spitzer bullet tip (shaped and polished) and my problems stopped. I have also on my factory Dillon dies done the same adjustment and it help a lot too. I also build some "wings" out of cardboard that I hot glued on the side of the primer chute when I load 44 magnum. That one caliber and the factory Dillon dies make me nuts!

I started to use a 1" 1/16 roll pin that I had to trip a bit. That sucker never bends or deforms. I have it fit tight on the center housing and loose on the outside sheet metal housing which i had to drill out a bit so it would pivot freely. I put a drop of red lock tight on the pin where it goes though the inter-housing and it has been there for the last 5 years with no issues. Bought a small magnet at Home Depot to put on the primer chute for a bit of weight on the outer housing towards the top. My primer drop always works now. JW

OK, if I hijack this thread, feel free to delete this posting. I have had issues with my throwers over the years having varied weights so I have done a little modification to my throwers that seem to help for me to keep the charges constantly and keep it from bleeding H110 powder. I have attached 4 pictures to show what I do. I take out the powder bar spacer and shim and tap the hole where the plastic plug goes to a 10-32 screw. I put the shim on the top side so it doesn't wear against the moving powder bar. I have used aluminum coke cans for a spacer but are a PITA to cut out and install. So I use Aluminum HVAC tape that I bought at Lowe's. One layer is all that is needed on most powder throwers. After I cut it out I will press it down and slide it around my table to make sure it is fully stuck and flat. I have run it along a large file to knock off burrs and high spots. Secondly, related to Tightgroup posting I was reloading this week and did a experiment on my 650XL press (yes, I know the question was based on a 550 press but I think the results will be of interest) to see the constancy of the powder thrower when using the newer fail safe system and the older system of springs for the powder bar return. Full powder thrower with .013 setting with a Prairie Dog 6-120 powder micrometer (3.0 grs of TG) with a Unique Tek powder baffle in place. Same thrower was used and scale used was a calibrated Gem Pro 250 scale. The procedure was load at the normal pace of loading and pull 9 cases off full of powder with no hesitation to be weighted. I would load 20 cases first to make sure the powder hopper was settled I would use a total of 35 cases with 10 as a spare in case I spilled or I hesitated in the cycle of the handle. With older system spring return 3.08 3.14 3.16 3.20 3.30 3.28 3.14 3.18 3.14 28.62 total or avg 3.18 Hi 3.30 Lo 3.08 Spread .22 Fail Safe system 3.00 3.02 3.04 2.94 3.04 3.04 3.10 3.04 3.00 27.22 total or avg 3.04 Hi 3.10 Lo 2.94 Spread .16 Thank you, JW

I would call Dillon, it sounds like your base of your primer shield is worn beyond specs or your primer slides are trashed which allows the primer slide to move beyond the factory spec. I have had mine get pretty worn. Sometimes you can just use a new primer slide assembly to fix it, other times you'll need a new primer slide and a new primer shield assembly. One reason the primer cup assembly has such a big head, is to allow it to 'self-center' when it retracts into the primer shield, you'll have some wear, that is normal, but when it starts to hang up, that is something different. One issue the priming system on 550 can be troublesome, is because it is not a balanced system. The op-rod puts side force on the primer slide during the cycle, which in turn cause it to cant and bind. Good luck, JW

I have bent and re-bent mine a several times. Especially when I pull the handle with it empty and not paying attention to the location of the shellplate. I have just bent it back. No issues so fare. . . . .

I have also had the issue, I lube my brass with Dillon lube and have found the lube residue will build up in fingers of the case feed plate causing the brass to "stick" for just a second before it drops. If I clean the plate regularly, my jams nearly stop when on Hi. Jw

I totally hate when my 550 pukes primers too. If my Op Rod Bracket is slightly off, it goes stupid, so I have to make sure that it is parallel with the primer slide as it moves back and forth.

I have sent you an personal message. Thank you, Jeff

JW, how are the new micrometers? Did you get a chance to check them out yet? Sorry for my absence, I have been pretty busy with my side job. To answer the question, they work good. I have screwed them in and out checking them with my scale. They are spot on, all three of them. the wire wrapped around the shaft is a bit hooky, but it works. If it gets worn, I'll just strip some wire and re-wrap or try the washer shimming. But for now, I'm happy with my 4. Jeff

Well, Sunday I bought 3 more. So I guess I like them. I have been using mine to load 3K+ 9mm and found it to hold the charge weight after several different loading sessions (I unload powder hoppers at the end of each session). I had some problems with my first one having too much slop- which they fixes, but they told me it has been fixed in the production side. I should have my 3 new ones this weekend. I'll try to post reviews once I get them. JW

Here is some important numbers I keep track of with the 550 Priming Systems that I use as a reference of a known working system that I have shared with a few people. The Op rod was brand new out of a package. Enjoy JW

I love loading 300 Blackout, nothing like a case full of super fine ball powder. Every time I rotate the shell plate, I pray that I don't ham hand it and throw powder everywhere!

In my years of loading on 550's couple of issues are to blame most of the time will cause the primer system to cause issues of the primer slide sticking back and studdering. The primer spring return have never worn out. The system runs on a balance of several things. 1# is Swelling of the 5/32 threaded area from over tightening (inside the primer slide track)op rod losing tension through use, re/blue tips on primer tube will look good, but be worn out and general cleanness. I recommend get a new op rod from Dillon, trace it on a piece of paper for future refrence. Happy loading and happy turkey day too! Jeff

I forgot to finish the story, I called them and they paid for me to ship it back to them for inspection and or repair. They shipped it back to me back within a week of receiving it with a new threaded part installed between the two E-clips. When I pulled it out it felt nice and tight with no movement. I was happy. I got home and started to install it, I noticed a very fine wire was twisted around the shaft, between the E-Clip and the threaded sleeve. So being a typical man, I messed with it and caused it to fall off. The slop between the E-clip and threaded shaft was .003-.005" of play (used feeler gauge). So I found some small gauge wire, striped it, got a few strands of copper wire and replaced it. The wire removed the slop issue and the threaded sleeve still turned freely. I reinstalled it and threw some charges to watch the constancy, it drops powder at the same rate as the factory Dillon powder bar does. It will fluctuate .04-.08 grains, which is less than .1 grain. I'm happy overall, however I will be watching the wire to see if it stays put. I think I am going to buy another one for my rifle powder bar. Time will tell if it is a permant fix.

To disassemble the priming system, remove the spring from the bottom of the primer slide, remove the two 5/32 bolts that are on the bottom of the primer tube assembly. Unhook the op rod and your done.

OK, finally had some time to run it and see how it works. My initial impression is very positive I even recommended it to a fellow shooter who messaged me up. I found the adjustments in the micrometer head to be very positive and tight. I like the laser engraved on shaft, no numbers to wear off. Just messing around it would hold +/- 0.2 grains which I thought would settle down once I got powder settled in the hopper. Not so positive, after loading 200 rounds of 3.3gr of Clays, the checked powder throws varied from 3.22 to 3.46gr using a warmed up, calibrated, Gempro 250 digital scale. I checked it approximately 10 times during the run of ammo waiting for it to settle down, but this is too much for my taste. I put on a factory powder bar with the 1/4" bolt to use as my baseline. I have one factory powder bar that will hold .1 grain and I checked it again using the scale 3.27 to 3.35gr which is fine by me. I think I found the cause. . . .there is about .010" of slop on the spindle where the threaded screw rides between the two E-clips. That translates to approximately 1/4-1/2 turn on the factory powder bar, hence why the powder charges varied so much. You can maybe see on the pic the gap between the clip and the threaded part. I plan to contact the manufacturer tomorrow and see if they will offer a solution, however I have several ideas on how to "fix" it if they they offer no solutions. I'll post when I have an update. Jeff