10-Hole Hero:
Magazine Bottom
SLIGHT DIFFERENCE OF THE MAGAZINE BOTTOM
fig. 1: Movie still of the 10-Hole Hero Pulse Rifle magazine being inserted into the rifle.
On the 10-Hole Hero Pulse Rifle, the mag bottom seems to be made of a single block, either aluminum (most likely, as it shows the same signs of weathering as the aluminum shrouds) or some cast material. It is unclear how it was attached to the Thompson M1A1 magazine itself, but there don't seem to be any screws, neither on the magazine bottom nor on the "clip" surrounding the magazine. It must be noted that the "clip" has an opening on the rear, so it might have been inserted from the front.
Several Pulse Rifle replicas have the small "magazine tabs" that are seen on the side of the shrouds, just above the magazine, as part of the magazine bottom or release mechanism. On the original Hero Pulse Rifles, these parts were directly riveted to the shrouds and not connected to the magazine bottom in any way.
Whereas the 10-Hole-Hero used a solid magazine bottom, the Delta Pulse Rifle seems to utilize a magazine bottom that consists of a central block - which seems to be manufactured from aluminum - that has been wrapped into an aluminum outer shell. This shell is attached to the inner block with two screws on either side of the magazine bottom (see particularly this photo here).
Notice that the Thompson M1A1 magazine is also not held in place by a small "clip" as in the above image of the 10-Hole Hero Pulse Rifle, but is wrapped in some sort of sheet metal with a much higher profile.
It seems that this is unique to the Delta Pulse Rifle and possibly added after filming, since the few available shots of magazine bottoms show the "clip" style.
fig. 2: Movie still of a bunch of magazines confiscated, showing the magazine bottoms.
My Magazine Bottom
fig. 3: Movie still of the 10-Hole Hero Pulse Rifle magazine bottom, which looks like a solid aluminum base held onto the mag by a clip.
I wanted to use an aluminum Magazine Bottom on my replica M41-A Pulse Rifle, but was not entirely happy with the available choices since I need access to the bottom of the magazine (I have a GBBR Thompson) and therefore need a way to quickly remove the magazine bottom to fill with gas.
I also wanted the final look to be as screen-accurate as possible, and the idea was to have a magazine bottom that could be adapted to magazines of different lengths and possibly from different manufacturers.
So I came up with a design where only the actual magazine bottom is made of aluminum and the rest can be 3D printed. The reason for this is two-fold: First of all the "clip" at the top needs to be flexible (see below) and secondly this allows the mechanism to be customized for different magazines.
I had the actual magazine bottom CNC-machined in aluminum, the rest of the parts can be 3D printed. I had them printed at shapeways.com, if you want to print them directly based on my templates, here is the link:
https://www.shapeways.com/shops/xhiwar
The inset can be screwed directly into the magazine bottom with two M3 screws (8mm length will do the trick). The magazine clamp slides onto the small lips at the bottom of the magazine, and the clip snaps the thing in place. That's why it needs to be flexible, so that it can flex over the rails. I don't think that could be done in aluminum.
Here is a video of my prototype parts, it works flawlessly:
fig. 4: 3D Render of my magazine mechanism. Base is separate to allow aluminum construction while allowing different mag types.
Below you can download all 3D files and have the parts made yourself. Please note that the mag bottom is based on the HCG aluminum shrouds and will need to be modified if you want to use it with different shrouds (for example, the Snow Wolf magazine well is longer and the mag base will be too short). I have made two different versions of the magazine clamp, one for the WE M1A1 GBBR and one for a real Auto Ordnance M1A1 magazine. If you are using a live-fire Thompson, please note that I have no way of testing whether the 3D printed parts will hold up!
NOTE: THE AUTO ORDNANCE MAG BASE WILL WORK WITH A REAL AUTO ORDNANCE MAG! I HAVE TESTED IT MYSELF. BUT SINCE I DO NOT OWN A REAL THOMPSON M1A1, I CANNOT CONFIRM IF IT WILL WORK IN A SETUP WITH REAL M1A1 and HGC SHROUDS...
