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David Christian

Precision rifle loading?

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Greetings, during this Covid break I recently switched from a single stage press to a Dillon 750 powered by a Mark 7 autodrive.  I shoot long range F-Open very competitively, loading .284 Win, shooting roughly 6,000 rounds a season.  I have not been able to find much support online, so I have been testing as I go and have made a few tweaks and observations to my system to dial in more precise rounds.  

1.  I had to hone the bottom of my shell plate, removing 2 highspots that were roughly .0015 thick.  
2.  I installed a thrust bearing on top of the shell plate and under the main bolt so that I could tighten down the shell plate as much as possible while still allowing the plate to rotate freely.  I have virtually zero slop in the plate now.

3.  My depth index is set at zero and I still could not get my primers to seat much below flush and not knowing any better, I removed the primer pin from the slide rail and put a few mini circle pieces of paper under the primer pin (down the hole), thus lifting the pin .006 in height.  No idea if there is a better way to adjust this...but my primers now bottom out in the case, .005 - .007 below flush.

4.  I am using Whidden floating toolheads and am floating my sizer, expander mandrel, and seating dies.  Here is where I have my first main question.  For both the sizing step and my seating step I am in pursuit of .001 tolerances.  Today I found a way to reach this while sizing, but I am now having the crank slightly cam over while it is all the way at the top and the knuckles are slightly “pinging” or “knocking” against the horizontal support bar.

If I have my dies set up and hit calibration, the machine touches the sizing die on the upstroke, calibrates at the top end and finishes.  If I then run a case it does not fully resize my brass or I get inconsistent results.  In testing today I backed out my sizing die, hit calibration (allowing the ram to go a bit higher than with the die screwed all the way down).  I then turned my sizing die back in and started sizing brass.  Under this set up, my brass is coming out very consistent as any slop in the system has been removed due to the slight cam over, but I am getting the “ping” from the knuckles.  

Am I using the system correctly?  Is there a different solution to my end goal?  I have the digital clutch set at 5 and it works under this condition, should it be higher? I am new to the autodrive so I am open to all suggestions.  Thank you.


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I was getting some torque sense stoppages during calibration, and when the index ring was hitting the cam block on my 650. I had the settings pretty high.  It was suggested to lube the index ring/pawl with more grease, so I watched the Dillon video for lubrication on Youtube, and essentially you want grease on every place where metal touches plastic, and 30w motor oil on the shaft. The downside to more lubrication is if you get any powder spillage from a primer not getting seated, or slop on indexing, it really gets the press pretty nasty. With the XL650's rotary primer mechanism, this led to more issues with the primer feed. I've since swapped the 650 out for a 750, and have been doing some reorganization and haven't loaded anything on the autodrive yet for the 750. I also use case lube for everything, where I rarely used it except for rifle in the past. I use Brass Juice, and it works really well.

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