MDRL Valve Mods
Posted: Sun Mar 15, 2015 10:39 am
My MDRL is a stock Gen I 25 cal Mrod.
I like the low Es of my Synrod, and my goal is the same power and Es, but for 24 shots. Four shots should come from the MM airtube ext, and hoping to get the other 4 from valve mods. For reference, my Stock Gen II is tuned to 860-870-860 for 16 shots with Kings on a 3K fill.
I started with a Gen II valve which has a heavier return spring than Gen I. This helps with lower Es, but limits peak power. Here are the mods to the Gen II Valve:
- Inlet: 0.295"
- Body: 0.495"
- Exhaust: 0.160"
- TP: 0.150"
The Stock Gen I:
- Inlet: 0.275"
- Body: 0.405"
- Exhaust: 0.140"
- TP: 0.140"
As you can see, only minor changes. I made these mods to the valve a couple of months ago. I used a hand drill and a 0.495" reamer for the valve body. The rest were fractional or number drill bits.
My next step is to mod the gauge block to reclaim a few cc of air that the depinger takes up. I just plan to open up each end, but not the middle. I did make a "D" in the middle on my reg gun, but not going through the trouble here.
Gauge Block:
I just used a 5/8" spade bit and drilled down into each end to 1/2" depth. That leaves plenty of "meat" to the gauge block. I rolled up some thin plastic to fit down the existing hole to center the spade bit.
I like the low Es of my Synrod, and my goal is the same power and Es, but for 24 shots. Four shots should come from the MM airtube ext, and hoping to get the other 4 from valve mods. For reference, my Stock Gen II is tuned to 860-870-860 for 16 shots with Kings on a 3K fill.
I started with a Gen II valve which has a heavier return spring than Gen I. This helps with lower Es, but limits peak power. Here are the mods to the Gen II Valve:
- Inlet: 0.295"
- Body: 0.495"
- Exhaust: 0.160"
- TP: 0.150"
The Stock Gen I:
- Inlet: 0.275"
- Body: 0.405"
- Exhaust: 0.140"
- TP: 0.140"
As you can see, only minor changes. I made these mods to the valve a couple of months ago. I used a hand drill and a 0.495" reamer for the valve body. The rest were fractional or number drill bits.
My next step is to mod the gauge block to reclaim a few cc of air that the depinger takes up. I just plan to open up each end, but not the middle. I did make a "D" in the middle on my reg gun, but not going through the trouble here.
Gauge Block:
I just used a 5/8" spade bit and drilled down into each end to 1/2" depth. That leaves plenty of "meat" to the gauge block. I rolled up some thin plastic to fit down the existing hole to center the spade bit.