Tuning Marauder F&T .22 New Build

[Meanadidas]

I have a stock F&T and plan to incrementaly upgrade it for more power & ammo choices. I have a Lothar Walther .22 un-choked polygon barrel arriving today. I will machine the barrel to factory port for now and tune. Haven't decided if I want to incorporate the factory sgroud system or machine barrel end for 1/2-20 for DonnyFL. I plan to machine the barrel to 22in. I also replaced the OEM regulator with Huma w/o gauge and also have the Huma Quick Fill w/ gauge that attaches on tube end. I may machine the OEM gauge block for larger plenum and relocate a gauge to the side to monitor reg pressure.

Soon after, I plan to add the Hill upgraded valve assembly, peek striker, heavier spring, HF port, over-molded valve, etc.

If I can gain 23gr NSA slug performance, great. However I hope to shoot the JSB Beast & Redesigned with pinpoint accuracy.

I'm looking to get a little bit more ammo versatility and range and I enjoy my Marauders tremendously!

 

[UCChris]

Sounds like a plan! I'm excited to follow your progress!

 

[Meanadidas]

Sounds like a plan! I'm excited to follow your progress!

I'm looking forward to it too. I may also use some black high lubricity polymer and make a single shot tray but is still magazine-revert friendly. I have been wanting to build a custom, high output Marauder for some time now.

Depending on what I learn here, I may move forward with a ambitious .30 cal, dual- bottle, dual regulated, version. 

Just because I need something to do. 

 

[Meanadidas]

So I have over since the barrel o-ring hurdle. Now I need to get the internal specs right...



Would anyone happen to know the internal barrel dimensions, specifically the area after the o-ring but before the lands. I'm thinking a ball mill may make for a smooth transition to the lands. I'm assuming the small dwell after the o-ring in maybe .218 -.220" ID?

 

[Meanadidas]

I'm sure most everyone knows that the F&T has a longer tube:

Here are the OEM components in order starting from trigger side on left:

My plan is to remove the OEM regulator, and move the gauge port against the valve, then place Huma reg against gauge port. The vent hole for OEM reg is captured in the dead space between o-rings on gauge port and new "vent" will be original gauge port hole in tube:

*I want a separate gauge to monitor reg pressure. A Sekhmet digital is perfect as it can show me precise readings.

*Any possible air escape passages are still blockled off with o-rings except where the Huma butts against the gauge port. This particular gauge port has vent notches on both faces so I will machine one face so the Huma o-ring has a solid surface to seal against.

*The new gauge will be located on the right side of the gun for easy viewing.

Does anyone know what this is? It was inside the air tube in front of the gauge port:

 

[KatoKevin454]

That is a Depinger...... it should be place center of the air tube for best effect.

 

[2L8]

Meanadidas

Nice project with a very good platform, and quite an ambitious project as well. At one point I too had both a 2018 Marauder using Crosman's new barrel making machinery and a Marauder F&T with regulator and LW barrel. Both very fine PCP's. Appreciated the longer air tube that came with the reged FT but over all my standard Crosman barrel shot better than the LW. My project was simple in that I figured after finding the best attributes of each I would reassemble the Marauders with the best parts resulting in a near "perfect" Marauder. It was possible, then I found an FX Dreamline at an unreal deal for the same price I paid for the Marauder F&T and that has been a game changer for me. I do have a Prod though and love it!!!

 

[Meanadidas]

That is a Depinger...... it should be place center of the air tube for best effect.

Great, thanks for the identification!

 

[Meanadidas]

Meanadidas

Nice project with a very good platform, and quite an ambitious project as well. At one point I too had both a 2018 Marauder using Crosman's new barrel making machinery and a Marauder F&T with regulator and LW barrel. Both very fine PCP's. Appreciated the longer air tube that came with the reged FT but over all my standard Crosman barrel shot better than the LW. My project was simple in that I figured after finding the best attributes of each I would reassemble the Marauders with the best parts resulting in a near "perfect" Marauder. It was possible, then I found an FX Dreamline at an unreal deal for the same price I paid for the Marauder F&T and that has been a game changer for me. I do have a Prod though and love it!!!



Nice, and that's totally understandable. The Dreamline is next level compared to the Marauder! 

I want to create a powerful, sweet looking,"set & forget" rifle in a Marauder that I can pass down and provide years of reliable shooting. Plus I like tinkering.

I just picked up a double-rube prod from a member here and I have some upgrades planned for it too including a 3d printed AR-15 styled grip and 17.5" LW barrel.