To get the open side down case feeding to work there is an additional step needed to modify the plate. First I will try to explain the concept.
Regular case feeding of pistol brass works on the principal that the open side has less mass then the closed side. If brass falls in a slot base side up, as it approaches the top of the case feeder gravity takes over and causes it flip out of the the slot and fall back down to the bottom. My solution uses the same principal of the mass difference but in a different way.
First, the plate must be tall enough to not allow the brass to flip out as it approaches the top. It must also be tall enough so that when it hits the ramp it will not flip out of the slot. I found that with 45acp brass 26mm was the required height.
There must be a pivot point in the center of the slot in the plate, so that when the brass hits the slide it will rock either forwards or backwards. If it is nose up, the base will rock inwards keeping it on the slide and allowing it to pass the drop hole. If it is nose down it will rock outwards, causing it to fall in the hole. If you watch the video you will see this rocking motion in action. Adding the pivot point to the plate is the modification that must be made. If I was good enough with scad I would have tried to program it to print with the pivot, but I am not (maybe someone can with more scad experience can help with this). I did it with #2 x 1/4" sheet metal screws and a small dab of epoxy.
The drop hole must also be expanded, because of the larger diameter as well as the increased height of the brass. I found that with the standard 16mm drop hole the brass kept getting stuck on its way down because the plate would jam it up. I created the funnel spring adapter to account for the larger hole.
I also found that the standard ramp did not work to flip the brass nose down. The brass would end up flipping out of the plate. I modified the ramp to have a very thin ridge that captures the groove in the rim of the brass. This keeps it in place and allows it to flip in the plate slot. The modified ramp has worked fine for flipping my boolits as well, so no need to swap it out when changing between the two.
Lastly, the case feeder needs to be run at a steeper angle then with boolit feeding. This is required to get a reliable rocking motion when the brass hits the slide. I created the snap on back wall extender to account for this increase in angle.
I have attached a pic of the pivot point modification.
Last edited by TylerR; 06-05-2020 at 08:50 PM.
Wow.. that's pretty impressive thinking. Do you have a pic of the ramp?
Just realized I didn't really explain the point of the epoxy. The dab of epoxy at top of the screw is to prevent the mouth of the case from hanging up on it when it slides in to the slot. If you try running it without it you will see what I mean. Like I said, it would be ideal to modify the scad to include the pivot point. Where are the scad geniuses???
I just eyeballed the mid point. Drilled a small pilot hole and put the #2 screw in.
This is a mock up of what would be ideal for the pivot.
Last edited by TylerR; 06-05-2020 at 08:35 PM.
Hi Ed,
I just measured the the #2 screw and it is about 1.5mm depth. So figure the pivot should jut out 1.5-2mm.
I sent you the scad file. Also should mention I added a parameter that was not in the original Ammomike file. It allows you to change how many hole slots are generated.
hole_multiplier=1.5; // Number of Holes
Really appreciate your expertise with this.
Hopefully, I'll be able to figure it out. The hard part is changing it from a hole (difference) to a projection. It's kind of hard because you have to add it after all the bullet slots are formed.
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Growing old is mandatory, growing up is totally optional!
With the help of RedlegEd (Thanks Ed!) we have come up with a new version of the scad file that has a few new features. First Ed figured out the pivots, which is pretty impressive. We also combined the hex and T-slot versions in to one. Both the pivots and shaft options are now parameters you can turn on or off. There is also an option for controlling how many holes are generated.
The new options are:
hole_multiplier=1.5; // Modify the number of holes
addPivots = false; // Add pivots for brass feeding
useHex = false; // Set true if using hex shaft
I also added the correct settings for 45 acp brass in the examples.
The new file has been uploaded.
Can you please post the updated link for the scad file here?
Copy that, thank you
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Growing old is mandatory, growing up is totally optional!
nice. to bad we dont have something like this for the Bullet Feeder Die.
There is so much data here, and multiple file options.
What are the advantages of the different motor mounting rotations (0,90,270)
I am setting up for 556 initially, can someone compile a complete list of parts i need to print?
I feel like the majority of my confusion is surrounding the drop tube. Based on file names it looks there there are lots of options
BP | Bronze Point | IMR | Improved Military Rifle | PTD | Pointed |
BR | Bench Rest | M | Magnum | RN | Round Nose |
BT | Boat Tail | PL | Power-Lokt | SP | Soft Point |
C | Compressed Charge | PR | Primer | SPCL | Soft Point "Core-Lokt" |
HP | Hollow Point | PSPCL | Pointed Soft Point "Core Lokt" | C.O.L. | Cartridge Overall Length |
PSP | Pointed Soft Point | Spz | Spitzer Point | SBT | Spitzer Boat Tail |
LRN | Lead Round Nose | LWC | Lead Wad Cutter | LSWC | Lead Semi Wad Cutter |
GC | Gas Check |