Shotshell Reloading with the Dillon SL900 – Hands On!

Shotgun ammunition goes FAST. To keep up, we’ve got the Dillon Precision SL900 Shotshell Reloader


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About the Dillon SL900

I’ve loaded on Dillon presses for a number of years, but this is a first for me! I’d never seen the SL900 press before – it is quite impressive! 

From Dillon Precision:

The SL900 Shotshell Reloading Machine Features:

    • Available as a 12, 20 or 28 Gauge Loader
    • Loads up to 2 3/4″ shells
    • Loads #6-#8 size shot
    • Automatic Indexing
    • Auto Powder / Priming Systems
    • Adjustable Case-Activated Shot System
    • Tilt-Out Wad Guide
    • Aluminum Roller Handle standard
    • The Automatic Casefeeder system shown  is optional. 

The SL900 ships with easily adjustable, case-activated, powder and shot systems that eliminate troublesome bushing changes along with spilled powder and shot. The powder measure is the same proven design – renowned for its accuracy (within one-tenth of a gr) and consistency – that we use on our metallic cartridge reloaders. Our adjustable shot dispenser uses the same design principle, with an extra large hopper that holds 25 pounds of shot.

The frame is a heavy duty O-frame design, precision CNC machined to exacting tolerances. Switching from one gauge to another is easy, because the SL900 features Dillon’s famous interchangeable toolhead design. The toolhead assembly simply slides out of the frame, keeping all your critical die and measurement adjustments intact. Each machine comes with factory adjusted dies.

The SL900 comes with a lifetime warranty against manufacturing defects and normal wear and tear. Electrical and electronic components have a one year warranty.

What’s in the Box

The box contents took up my entire reloading bench.

The press itself comes fully setup with a dummy 12 gauge cartridge. Also included is a hull drop tube, deflection chute, shell bin, strong mount plates, roller handle, powder measure, powder measure return and stop, bosses and support poles, hardware, Allen keys, crimping dies and inserts, shot system, shot reservoir, and instruction manual. 


While the SL900 came with strong mount plates, I used an Inline Fabrication mount with quick-detach top plate as our Ultimate Reloader Bench System is optimized for it.

With the press mounted, I added the handle and removed some extra pieces: the test shell, rubber band, and remove before flight flag.

The SL900 instruction manual included thorough, detailed instructions for bolting the case feed and shot system support poles in place.

The shot reservoir fit neatly over the appropriate pole. The case feed bowl and plate are sold separately, so I unboxed those items and set the bowl on the opposite pole, clicking the drop tube into place.

The case feed system requires power and came with the standard assortment of international connector options. After ensuring the power worked, I installed the case feed plate.

The powder measure was easy to add: loosen the two clamp screws, slide it down over the top of the powder die, tighten the screws (finger-tight), drop the return rod down, clip in the plastic boss under the cutout at the bottom, and tighten the screws all the way when you’re satisfied.

A clear, rubber hose secures to two connectors with clamps. These clamps hold the shot tube to the shot reservoir and lower station.

The return rod finishes out the shot delivery system.

With this in place, I ensured there was a bit of spring compression at the very bottom of the stroke for primer actuation.

Next, I secured the spent primer cup, shell chute, and placed the shell bin. 


I placed the Fiocchi primers face-down in the primer reservoir, and carefully lifted the plastic. 

With all the primers in the correct orientation, I lifted the “floodgate,” allowing all of the primers to slide into place.

Next I filled the powder and shot reservoirs.

With the components in place, I made sure the primers fed properly and ran one hull through the machine to verify priming and the appropriate powder charge.

I repeated this process to establish a baseline and consistency. 

The powder jug recommended 19.2 grains of Hodgdon International for our Winchester AA wad and 1 ⅛ oz. shot.

I did have to make some adjustments to the powder measure to reach this weight.

Still working with a single shell, I added a wad, shot, and  crimped it twice. The finished product had a bit of a gap at the top, indicating I needed to lower one or both of the crimp stations (stations 4 and 5). After making some adjustments, I ran another single hull through the machine and monitored progress. It turned out perfectly this time! 

I placed wads in an extra bin to the side of the press for easy access and dumped a few handfuls of hulls into the case feed bowl.

Station 1 deprimes and sizes the hull. Station 2 primes the hull— powder drops at the top of the stroke. 

When the shell is in station 3, you need to feed a wad into the wad holder. Shot drops at the top of the stroke.

Station 4 and 5 crimp the shell. Once complete, it kicks off the plate down the shell chute, and into the bin. 


Before loading too many shells, I wanted to test them in my Mossberg 500 shotgun.

All performed well and got me excited about shooting shotgun again. It’s been awhile! 


The Dillon SL900 worked just as wonderfully as I had hoped: tried and true Dillon Precision quality with a host of great features. Looking forward, I’m planning to try some different hulls and upgrade my current shotgun. 

Get the Gear

Dillon SL900

Dillon Variable Speed Case Feeder

Dillon 12 Gauge Case Feed Plate

Inline Fabrication Ultramount 

Hodgdon International Shotgun Powder at Midsouth Shooters Supply

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Gavin Gear

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