The 50 round mini hopper is a neat little gravity feed 50 round hopper used by players that don't have the need for a high volume of paint fed into their marker. You'll most likely see them on mechanical or pump markers. The most noticeable difference between this hopper and the 50 round hoppers of the past is its wide feed mouth. You can load these much quicker using the high capacity paintball pods available as opposed to the small 10 round tubes of the past. There are ways to improve this hopper from its stock configuration. I will outline these modifications in this article as well as give you a tip how to lower the capacity of the pods to better suit this small hoppers needs.
Feedneck Adapter
I recently fabricated an adapter that fits inside the neck of the hopper to prevent it from slipping off the feedneck or adapter of the marker when tightened down. These hoppers are made of a flexible plastic material. When you tighten down the clamping device on the feedneck of the marker, it doesn't really have a positively solid hold to the hopper neck. Some use electrical tape to increase the bond of the parts but frankly that can become a nasty sticky mess in due time.
The inside of the hopper neck is around 7/8". The diameter of a .68 calibre paintball is a relative 11/16". The inside diameter of the thin wall 7/8" tubing I used is a little over 3/4" so even after adding the tubing there's still almost a 1/8" gap past the outer diameter of the paintball. Plenty of room for the ball to pass through without the worry of jamming up the feeding process as depicted by the photograph below.

I most likely have access to machinery and materials that you don't have readily available for use, so you may have to improvise those aspects of this modification. This is just a guide of ideas to feed your head. I will make some alternate suggestions as I go along to possibly remedy any short comings you may encounter.
The materials I used to make this adapter are a 1" outside diameter piece of stainless steel tubing and a 7/8" outside diameter thin wall piece of stainless steel tubing. After deburring the cut edges, they fit together easily for a slight press fit with the tap of a hammer. I secured the bond of the 2 pieces even further by placing a few evenly placed weldment tacks using a tig welder as you can probably see from the photo above. The length dimensions I felt most comfortable using with both these pieces was 13/16" for the longer 7/8" diameter piece and 3/16" for the shorter 1" diameter piece. I cut about 3/8" length of plastic off the bottom of the hopper neck as well.
After bonding it all together I used a stationary vertical belt sander to flatten both the top and bottom surfaces then used a round file to cut a bevel into the inner top and bottom edges to remove any sharp edges that might encounter the paintballs. This is more important at the inner top edge to remove the ledge that now creates a smooth transition from the inner hopper surface to the inner adapter surface.

I also scratched grooves into the top outer portion of the adapter that fits into the hopper neck as shown above with the stationary vertical belt sander that created further grab between the two parts. From this point using a fine grit sandpaper to smooth out all the edges of the adapter is a good idea as well.
Alternates
All you're really doing here is solidifying the neck of the hopper by adding a piece of round metal to the inside of the hopper neck. An alternate means of doing so would be to simply add a 7/8" outside diameter piece of metal tubing to the inside neck surface of the hopper. The second 1" ring helps hold it in place and makes it easier to remove the adapter if needed but is not absolutely necessary.
There's not a necessity to use stainless steel. You could use any metal that doesn't have a tendency to rust such as aluminum, brass or copper. Use a pipe cutter to achieve nice flat ends. If you don't have the machinery I mentioned available, start your project by making sure the 7/8" tubing you're using fits into the neck of the hopper. You can sand off any excess by using a coarse grit sandpaper and at the same time scratch grooves into the outer portion of the adapter that fits into the hopper neck for a positive grab on the plastic. I would suggest working the metal into shape as a longer piece then cutting it to size and finishing the bottom edge last. This will make the task much easier than trying to modify it in the final shorter state if you don't have all the shop machinery I mentioned in the first portion of this article.
Stress Test

The results of adding this little adapter was impressive which was part of the inspiration for typing out this article in the first place. I can now carry the SPPS Compact/Compact around by the hopper with no worry of it falling off. Matter of fact I can shake it around, swing it, jiggle it or whatever holding just the hopper and the hopper's not going to budge from its locked in place. What's even more impressive is I can do this with the inexpensive plastic feedneck adapter Kingman provides with these markers. Not that I'll be carrying it around by the hopper in the first place but this assures me by far that this hopper's not going to budge from its place no matter what happens short of the plastic feedneck adapter completely cracking off. Stress test? Passed!
Fliptop Lid
These hoppers come equipped with a clear plastic removable lid. The mouth of the hopper has a slight lip on it so the plastic lid stays put when snapped in place. About 1/3 of the top portion of the mouth has a 1/2" flat ridge perpendicular to the hopper body.
I was scrounging through some of my old equipment and ran across some old Nasty Boys and Indian Springs 100 round pods that I haven't used in a coons age. Both styles just happened to have removable fliptop lids that simply slide over the top of the pods. Thinking that the lid assemblies of the pods might per chance fit the mouth of the 50 round hopper, I thought I'd give it a try. Well lo and behold, they fit perfectly! Matter of fact they fit so well I had one helluva time getting them over the lip of the hopper so for these lids, there's definitely no need for any glue or epoxy to hold them on. Adding this lid gives the hopper about 10 more rounds of capacity as well due to the extra space provided by the new fliptop lid.

These pods are about 15 years old so I'm not sure how the more recent vintage pods with removable tops will fit. If they are a little loose you could always use epoxy to hold them in place. Proof positive that being a paintball equipment pack rat can pay off in the future even if it is 15 years later.
50 round pods

Speaking of pods with removable lids, you can make your pods fit the capacity of the smaller capacity hopper by simply filling it to the capacity of choice then marking that level with a Sharpie marker. Once marked, cut a straight line around the circumference of the pod with an X-acto or utility knife. Fit the removable lid back on the pod and voila! You might consider making the pod capacity about 10 rounds short of the hopper capacity. Most players don't wait till the very last ball in the hopper to reload.
Technical Information