Rainmaker pump assistance

[oats944]

Thanks again to everyone that helped me complete this baby. Final pieces came in today and she’s ready for some field time.

[Jordan]

No problem! It's easy to nick those orings when inserting the valve and HPR block.

[oats944]

Thank you. I used some 2 part epoxy to seal that leak under the bolt cover detent per your advice. Stripped it down again and put in a spyder cup seal and same leak problem. I had already replaced the valve orings but put a different new oring on the rear-most part of the valve and now it’s good to go. You’re a life saver, thank you again for all the info!

[Jordan]

Hey y’all, chasing a leak now, hoping one of you fine gents might assist. First it was from where the back block inserts, then where I capped the hole in the hpr cylinder, then where the lpr connects, then from the capped velocity adjustment screw, then the cap opposite the macro line fitting, then from the bolt cover detent. Never all at the same time.

I replaced orings and Teflon tape as needed and finally gassed it up with no leaks. Took 3 shots and then a massive leak down the barrel. I messed around with the cup seal/spring with no luck. It’s looks in good shape. I’m assuming this is a cup seal issue? Since I can’t find spares anywhere online, will a cocker or other cup seal work?

Thanks so much guys

Double check the valve orings. One going bad will mimic a bad cupseal, ie: leak down barrel.

Cocker valve stems are too short to use, but a Spyder cupseal could potentially thread onto the RM valve stem.

[oats944]

Hey y’all, chasing a leak now, hoping one of you fine gents might assist. First it was from where the back block inserts, then where I capped the hole in the hpr cylinder, then where the lpr connects, then from the capped velocity adjustment screw, then the cap opposite the macro line fitting, then from the bolt cover detent. Never all at the same time.

I replaced orings and Teflon tape as needed and finally gassed it up with no leaks. Took 3 shots and then a massive leak down the barrel. I messed around with the cup seal/spring with no luck. It’s looks in good shape. I’m assuming this is a cup seal issue? Since I can’t find spares anywhere online, will a cocker or other cup seal work?

Thanks so much guys

[oats944]

Made some good progress the last week. My coat hanger sear is holding up well and managed to get a sniper pump handle mounted. Just need to find a non-jacked rear block to finish the ‘ole girl.

[Magoo]

Hah! That's a slick little solution! See, that's why I like Rainmakers. Just send it.

[glaman5266]

I do miss that one. Shouldn’t have traded it.

[oats944]

Thanks Magoo, I was messing with a straight rod attached to the trigger originally with no luck. I’m glad you mentioned bent rod. One coat hanger and pen spring later I have it reliably pumping and firing. A little janky if I do say so, but it works for now.

[Magoo]

I sold my pump to Glaman back in the day (when I was DeTrevni). Rainmakers used to be my jam. I've owned Rainmans Warped Painmaker, I've still got his raw Ultralight body, I've got an AKA valve tucked away, and yes, I have another original Rainman pump lying around somewhere right now. These things were the ultimate tinker fodder.

I don't know if the original question was answered, but the pump sear tripper was a bent rod directly attached to the trigger on an Angel LCD frame. I can't remember if it was pressed in or tacked. But the rounded part of the bent rod would trip the sear. Bang.

[oats944]

Ok awesome, thanks so much for your help Jordan!

[Jordan]

Hmmm that could be interesting. I did a little searching. Looks like a cocker trigger frame/lpr/3-way hooked up to the stock rainmaker ram? But unlike a cocker the trigger pull would just pull the hammer forward and trip it against the horizontal bar in the lower tube to fire? Hopefully that’s not way off.

Only downer is my leftovers don’t include a stock ram. Is there a generic ram out there that’s still available and would work in its place?

Yes, and yes.

Both Clippard and Bimba make a ram - or you can buy a Humphreys ram from PPS, the ram they use for Typhoons is the same IIRC - and yes, a Rainmaker is an auto triggering pump at it's core.

I did a sleeper mech conversion - William the Third owns it now, I believe - that used the stock frame with some pneumatics mounted inside.

[oats944]

Hmmm that could be interesting. I did a little searching. Looks like a cocker trigger frame/lpr/3-way hooked up to the stock rainmaker ram? But unlike a cocker the trigger pull would just pull the hammer forward and trip it against the horizontal bar in the lower tube to fire? Hopefully that’s not way off.

Only downer is my leftovers don’t include a stock ram. Is there a generic ram out there that’s still available and would work in its place?

[Jordan]

There’s a decent amount still there. I think enough to make a pump out of it, once I figure out the sear situation that is. But to restore it to its normal semi condition it would need the front plastic covers, ram, and board. The rear block was gutted so it would need either a new one of those, or an Automag vertical asa and hpr like my original one as pictured.

Sounds like a great mech-conversion project.

[oats944]

There’s a decent amount still there. I think enough to make a pump out of it, once I figure out the sear situation that is. But to restore it to its normal semi condition it would need the front plastic covers, ram, and board. The rear block was gutted so it would need either a new one of those, or an Automag vertical asa and hpr like my original one as pictured.