WickNJ
New Member
I’m late to the game, having been sitting on this project for at least 30 years. I had sold some of the parts I originally had due to financial issues. Had to purchase another SPAS Heat Shield & Grip, 20 Round magazine and magazine base.
I’ve separated the grip from the SPAS Cage using an excellent tutorial video
The end results
For the shotgun I chose to go with an airsoft replica Remington 870. Specifically the PPS Model M870 Police Magnum. Stripped it down of the grip and shoulder stock.
Spent some time swapping out the bolt with an upgraded machined Aluminum Bolt to match the original look of a Remington 870.
There was a bit of confusion on how to get everything back together again after taking apart the barrel, magazine tube etc. I couldn't figure out how to get all the components back in. It was not lining up and inserting back in. Searched YouTube and found the answer in this video. All in Japanese, but easy to follow along.
First steps are to cut up the SPAS Cage. The more challenging cut is going to be the ejection port on the SPAS.
To help with this I found a .step file provided by XHIWAR at his site pulserifle.net that he created of the SPAS Cage. Converted it into an STL and then imported it into MS 3D Builder. From there I chopped it down just to the ejection port section of the SPAS. Printed it out on my Elegoo Saturn resin printer and cleaned it up a bit.
Makes a perfect template to mark where I am going to do the cuts.
Marked out my SPAS Cage to start making the cuts. Started with the easy one on the left-hand side where the racking arm will be accessed. Made slots and slowly worked my way to the edge of the vent slot. Making sure it was even as possible.
Then it was on to the ejection port which was marked out from my template that I created. Started hogging out the material working my way as close as possible to where the curves would be. That was tedious to say the least. I went as far as I could and got tired. Took a lunch break.
Decided to leave that ejection port curves alone (too stressful) and went on to the front of the SPAS cage where the forward block was to be mounted. I placed the forward block and centered it, traced the outline with a mechanical pencil. Slowly cut that down and test the fitment. Got it to a point where it mounted snugly.
Satisfied with the way that came out I started working on the back end of the SPAS cage. Pressed the flat sections against my 5" disc sander to thin out the metal and make using my Dremel cutoff discs easy to trim it down. Once I got close to the edge I went in with a drum sander & file to smooth it out flat. You can see in the photo below that I outlined that area in red. All open now for the next step.
Moment of truth at this point. Took my PPS M870 and with a little persuasion it slid into the cage perfectly! Very happy at this point. Checked to see that the PPS M870 ejection port lined up with where I made the cuts into the SPAS, and it did.
Then I went on to tackle the underside of the SPAS cage where the shell loading port was and the trigger area. I 3D printed another template and marked my lines.
Started out with the notched area which was quick and easy. Will refine that later.
Then onto the shell loading port. Cut everything down as close to the line I could. Still needs widening in the forward part, which I will tackle later.
At this point I called it a day. Challenge is still going to be dealing with the curves and refining the ejection port. Drum sanders and filing are going to be the key, go slowly and carefully getting close to the lines.
I discovered that my files are for finishing and are not removing a lot of material. After a bit of research I had to purchase a bas-tard-cut file. 8” with one side curved and the other flat. Will help in shaping the ejection port.
This upcoming weekend I'll be cutting down my PPS M870. I’ve researched through my saved threads on the forums for how much I should cut down the Barrel, the Magazine and the Magazine Slide. There was one from a user by the name of schotti on the Aliens Legacy forums. He suggested these cuts:
Cut 14.1cm from the tip of the Barrel (141 mm)
Cut 14.4cm from the tip of Magazine tube (144 mm)
Cut 12.2cm behind the connector arms of the Magazine slide. (122 mm)
I don't know if that'll work, but I'm going to play with it. I'll use blue painters’ tape around the barrel cutoff area to see if it looks good. Measure a few times and then cut. Same with the magazine tube, just careful measuring and cutting it bit by bit until it fits the inside of the bottom of the forward block. I'm also concerned that the barrel is thin, because it is made of aluminum. So I either have to come up with some sort of cosmetic plug to simulate a real remington 870 or find a replacement barrel for the PPS M870 which is accurate. I think there is.
Until next time.
I’ve separated the grip from the SPAS Cage using an excellent tutorial video
The end results
For the shotgun I chose to go with an airsoft replica Remington 870. Specifically the PPS Model M870 Police Magnum. Stripped it down of the grip and shoulder stock.
Spent some time swapping out the bolt with an upgraded machined Aluminum Bolt to match the original look of a Remington 870.
There was a bit of confusion on how to get everything back together again after taking apart the barrel, magazine tube etc. I couldn't figure out how to get all the components back in. It was not lining up and inserting back in. Searched YouTube and found the answer in this video. All in Japanese, but easy to follow along.
First steps are to cut up the SPAS Cage. The more challenging cut is going to be the ejection port on the SPAS.
To help with this I found a .step file provided by XHIWAR at his site pulserifle.net that he created of the SPAS Cage. Converted it into an STL and then imported it into MS 3D Builder. From there I chopped it down just to the ejection port section of the SPAS. Printed it out on my Elegoo Saturn resin printer and cleaned it up a bit.
Makes a perfect template to mark where I am going to do the cuts.
Marked out my SPAS Cage to start making the cuts. Started with the easy one on the left-hand side where the racking arm will be accessed. Made slots and slowly worked my way to the edge of the vent slot. Making sure it was even as possible.
Then it was on to the ejection port which was marked out from my template that I created. Started hogging out the material working my way as close as possible to where the curves would be. That was tedious to say the least. I went as far as I could and got tired. Took a lunch break.
Decided to leave that ejection port curves alone (too stressful) and went on to the front of the SPAS cage where the forward block was to be mounted. I placed the forward block and centered it, traced the outline with a mechanical pencil. Slowly cut that down and test the fitment. Got it to a point where it mounted snugly.
Satisfied with the way that came out I started working on the back end of the SPAS cage. Pressed the flat sections against my 5" disc sander to thin out the metal and make using my Dremel cutoff discs easy to trim it down. Once I got close to the edge I went in with a drum sander & file to smooth it out flat. You can see in the photo below that I outlined that area in red. All open now for the next step.
Moment of truth at this point. Took my PPS M870 and with a little persuasion it slid into the cage perfectly! Very happy at this point. Checked to see that the PPS M870 ejection port lined up with where I made the cuts into the SPAS, and it did.
Then I went on to tackle the underside of the SPAS cage where the shell loading port was and the trigger area. I 3D printed another template and marked my lines.
Started out with the notched area which was quick and easy. Will refine that later.
Then onto the shell loading port. Cut everything down as close to the line I could. Still needs widening in the forward part, which I will tackle later.
At this point I called it a day. Challenge is still going to be dealing with the curves and refining the ejection port. Drum sanders and filing are going to be the key, go slowly and carefully getting close to the lines.
I discovered that my files are for finishing and are not removing a lot of material. After a bit of research I had to purchase a bas-tard-cut file. 8” with one side curved and the other flat. Will help in shaping the ejection port.
This upcoming weekend I'll be cutting down my PPS M870. I’ve researched through my saved threads on the forums for how much I should cut down the Barrel, the Magazine and the Magazine Slide. There was one from a user by the name of schotti on the Aliens Legacy forums. He suggested these cuts:
Cut 14.1cm from the tip of the Barrel (141 mm)
Cut 14.4cm from the tip of Magazine tube (144 mm)
Cut 12.2cm behind the connector arms of the Magazine slide. (122 mm)
I don't know if that'll work, but I'm going to play with it. I'll use blue painters’ tape around the barrel cutoff area to see if it looks good. Measure a few times and then cut. Same with the magazine tube, just careful measuring and cutting it bit by bit until it fits the inside of the bottom of the forward block. I'm also concerned that the barrel is thin, because it is made of aluminum. So I either have to come up with some sort of cosmetic plug to simulate a real remington 870 or find a replacement barrel for the PPS M870 which is accurate. I think there is.
Until next time.
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