Brass Eagle Rainmaker information

[Jordan]

MadMarty's site:

https://web.archive.org/web/20030623040751/http://madmartys.com/rainmaker.html

Old RMOG site: https://web.archive.org/web/20150925...ainman229.com/

Ram/carrier spacing:



Where to check on a real live ram and carrier assembly:

[Jordan]

Oring specs:

Valve orings - 017

HPR block - 017

Oring between HPR and LPR - 011

Oring between upper and lower receivers (seals air transfer port) - 011

[Jordan]

How To: Gut the stock regs

If you're reading this I have to assume you understand how to remove the HPR block from your Rainmaker. 🙂

1.) Start by removing the reg block from your RM. Watch out for the valve spring and cupseal. You should end up with this assembly:



2.) Unscrew the reg cap from the HPR and put the guts off to one side - you don't need those any more. Remove the LPR assembly from the HPR block and unscrew the reg cap, discard the piston and spring as well. I suggest clearly labeled plastic Ziploc baggies, but that's me. I'm not your dad, do what you want.

Don't lose the oring that seals both assemblies together, though.

You should have these assemblies now:




3.) You'll need snap ring pliers to make this next step easier, but a pick and some patience, along with a couple Band-aids after you stab yourself, will also accomplish it. (Just get some snap ring pliers.)

Remove the snap ring you exposed by unscrewing the reg cap, then use some pliers to pull the reg piston out.

You should be looking at something like this:




That will expose the reg seat holder. Use a large flat blade screwdriver to engage the slot cut into the seat holder and unscrew it. If you're hoping to reuse anything one day, grind a slot into the screwdriver blade to clear the reg pin.

You will end up with this:





Once you've removed the reg seat and pin, you can re-install the piston and snap ring to reseal the HPR block and still use an external reg.

The next steps are only if you want more volume behind the valve.


4.) The next steps are non-reversible and involve drilling, tapping, and Red Loctite (tm).

Take your gutted reg body and drill through the reg seat area, straight through to the end that slides into the lower receiver. Keep in mind that this also serves as a valve spring rest so you probably don't want to go any larger than 1/4".

You'll end up with this:




You'll also need to seal the reg cap - drill and tap the vent in the side of the cap for 1/4"-20 and loctite a setscrew in. You'll need to loctite the adjustment screw in the end of the cap as well.



5.) The last steps involve applying loctite to reg caps and screwing them onto reg blocks. You'll also need to plug the LPR output with something 10-32 threaded... a short bottomline screw or an appropriate setscrew with loctite will do the job.


That's it!

[Jordan]

MadMarty mods

What are MadMarty mods?

Rainmakers quickly gained a cult following - who couldn't appreciate a budget electro that was simple to use and maintain, took Cocker barrels and ran off both Co2 and HPA equally well?

They had flaws, though, and MadMarty was the guy who figured out what they were and how to fix them.

The biggest issues were the drive train - more specifically, the incredible amount of friction inherent in it's design.

Rainmakers (and Air Power Vectors, both designed by the same gentleman) are essentially an auto-cocking Sterling pump. The lower tube setup is almost a hybrid Nelson/Sheridan setup, with a Nelson style hammer striking a Sheridan style valve, in a stacked tube configuration, which means it shares the same issues as a Nelson hammer setup - namely, when the hammer latches up with the bolt, the spring attempts to push the hammer back against it's only contact point, the sear. This causes the hammer to arch away from the bolt, something anti-kink internals were developed to combat. Compare a stock Nelspot to one with Phantom internals and you'll see how much an improvement they can be.

MadMarty developed a series of modifications to perform to the hammer and carrier. The carrier performs the same function a bolt would in a Nelson - it provides a way to cycle the Rainmaker's bolt and gives the hammer something to latch onto, allowing the mainspring to be compressed.

A stock hammer and carrier look something like this:



The post threaded into the carrier is meant as an anti-kink measure - it indexes into a hollow machined into the hammer and also acts as a spring guide for the mainspring. Unfortunately, it still allows the hammer and carrier to arch apart, which over time causes excessive wear to the lower receiver and hammer, and in extreme cases causes the RM to cease functioning.

Another issue is the hammer is quite soft, and over time the steel valve stem wears a divot into the striking surface - you can see the wear in the hammer face in the picture.

There are three simple modifications to be performed, all of which can be performed with hand tools and a bit of mechanical aptitude. A drill press helps but is not mandatory.

The first thing to do is remove the carrier assembly from the ram - it will likely be loctited on, so a little heat may be required. After that, you'll need a bit of heat to remove the center post from the carrier. You'll be left with this:




Set the carrier aside but keep the center post out - you'll need it for the next step, modifying the hammer.



This modification does two things - it creates a durable striking surface to contact the valve stem, and adds mass to the hammer.


You'll start with drilling, using the appropriate drill for 10-32 threads:



Then tapping the hammer for 10-32:




Then install the center post in the hammer, using red loctite. File down any threads sticking out, aiming for flush or almost flush with the end of the hammer:



Moving onto the carrier assembly, you'll need a 10-32 shoulder bolt, like this:



The center post has a roughly .250 ID, perfect size for a 10-32 shoulder bolt with a 1/4" dia shoulder to fit into. It's going to act as the other half of our anti-kink internals we're creating. I recommend getting one at least an inch long and cutting to the required length.

Thread the bolt into the carrier, using red loctite, and cut the head of the bolt off. I gradually trim the remaining post down until it's just short enough to allow the hammer assembly to slide on and latch.

Your completed hammer and carrier assemblies will look like this:




One last modification is done to the carrier - the lip the hammer latches onto is rather abrupt and tends to slam into the latch instead of gently guiding it onto it's lip:




I use a flap wheel on a grinder to "machine" the lip down and round it off so it latches much easier.




The last modification involves installing a setscrew in the carrier... this screw is used to hold up up the bolt link, which prevents it from tipping forward during the bolt cycle, and reduces or eliminates wear on the top receiver.

No pictures of that, unfortunately... I may attempt to get pictures of the process on a spare carrier I have.

[Jordan]

Bolt linkage dimensions:

(Thanks Rainmaker !)

[Jordan]

Replacement ram options:

There are several options, I can tell you the specs are going to be 1/2" bore, 1" stroke, double-acting, stud mount, 10-32 thread ports/shaft.

Clippard makes a replacement - the number is SDR-08-1.