Author Topic: Building a Gen II .25 Marauder around JSB King Heavy MK IIs  (Read 250 times)

ShakySarge

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Building a Gen II .25 Marauder around JSB King Heavy MK IIs
« on: December 21, 2018, 08:33:45 PM »
Now I know this has been done probably over and over again but I am going to post this and update it as I go along regardless!!

I had most of the parts for another .25 Marauder in the Gen 2 flavor and after deciding to turn my Brod .25 heavy hitter into a .30, I found that I needed a new air gun to sling the King Heavies, oh darn right?! After a quick inventory of the parts I was short, I placed an order through Crosman, Pyramyd Air, and Discos R Us for the remaining pieces save the stock .25 valve that PeterL so graciously allowed me to buy. The valve arrived yesterday and I managed to sneak out to my shop to start in on the boring and polishing and to assemble the entire tube and lower assembly minus the stock. 

I decided not to go too big at first and settled on a .170 exhaust on the valve and a .186 transfer sleeve and then polished them both up with 1200 grit wet/dry sandpaper. Next, I replaced the heavy 0.06 wire valve spring with a lighter 0.03 spring that was just a slight bit longer at 1.49" compared to the stock 1.37" spring.

Next up was installing the gauge block and gauge which I replaced with a Ninja gauge as I have found them to be much more accurate and would accent the black synthetic stock quite nicely. I then installed the valve and secured it in place with the lug screws. Next up, I installed the end cap and fill probe along with the shroud guard. All the O-rings were lightly lubricated with Krytox GPL204 and each slid in snug as expected.

My next step was to fill the tube slowly to 2Kpsi and check for leaks, which there were none as I checked it again this morning and afternoon and it still read 2k.

Today I worked on the SSG and installed that, the trigger assembly, and the stock that arrived with great timing this afternoon. For now, it will sit as I await the .25 Armada breech which will allow the rest of the gun to be assembled.

More to follow as the build continues to come to light and be adjusted!


  • Clarksville, Tennessee
"It is good that war is so terrible; for we should grow too fond of it." GEN Robert E. Lee

Is it a coincidence that a group of baboons is called a Congress????????

Alan

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Re: Building a Gen II .25 Marauder around JSB King Heavy MK IIs
« Reply #1 on: December 22, 2018, 03:27:46 AM »
I can think of a lot of reasons to get one's fingers dirty. This project is at the top of the list!

  • Roswell, New Mexico
Alan

I have an Omega compressor. If you're a fellow Guild member, and you pass through Roswell, NM, I'll fill your portable tank as a courtesy.

ShakySarge

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Re: Building a Gen II .25 Marauder around JSB King Heavy MK IIs
« Reply #2 on: December 22, 2018, 07:34:36 AM »
Absolutely Alan. A little dirt on the hands is always a good time when tinkering with Air guns!
  • Clarksville, Tennessee
"It is good that war is so terrible; for we should grow too fond of it." GEN Robert E. Lee

Is it a coincidence that a group of baboons is called a Congress????????

ShakySarge

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  • Somebody had a bowl of stupid for breakfast!!!!
Re: Building a Gen II .25 Marauder around JSB King Heavy MK IIs
« Reply #3 on: December 27, 2018, 03:51:25 PM »
Received the Armada Breech today and went to work on the complete assembly this afternoon. The Armada breech required just a bit of "milling" to accept the Gen 1 Mrod Bolt assembly but a dremel made quick work of it. I went ahead and cut out the side of the receiver to be able to take the bolt out without removing the breech for easy cleaning. I installed the Gen 1 Mrod Barrel and shroud onto the Armada breech and secured it and then installed the 1/4" tubing and slapped it all together. Afterwards, I put a UTG Bugbuster scope on it and shot a couple magazines to check for accuracy, to which I found that it is highly accurate. Unfortunately the sun was already setting so chrony work and more accuracy testing, as well as velocity adjustments will have to be made tomorrow.

So far, The "Armaurader" is turning out to be a great little gun!!!
  • Clarksville, Tennessee
"It is good that war is so terrible; for we should grow too fond of it." GEN Robert E. Lee

Is it a coincidence that a group of baboons is called a Congress????????