Pump mag binding

[robertreed711]

So I just picked up a pump mag with a rainman pump kit. It works well if you pump it using the pump handle, very short and smooth stroke but if you try to pump it using the hitman mod it binds up.

All I can tell is there is just too much play between the center guide rod and the pump handle.....

I have no experience with these so I may be missing something, any advice is appreciated.

Of course, a pic for good measure

[need4reebs]

looks like tha pump rod is bent.

[robertreed711]

It is slightly bent but I don't believe that's what is causing the problem. Good eye though.

[BLachance75]

The rod does look bent down, at least in the middle.

Try taking the pump handle off of the back plate. I had to adjust my guide rod a little to get the pump to slide smoothly.

[dboggs79]

I've yet to see one of these pump kits that I've been impressed with yet. Every one I've seen, in person or in pictures seems to be off. I'm guessing a lot is due to loose tolerances. The other part i believe is because the two pump guides aren't long enough to give it a steady position at the front of the pump stroke. They all appear to be "nosed" downward when in the forward position. A lot of this honestly guessing . I've never had one taken apart and thoroughly inspected it. I did see where Rainman himself commented on the last run of these kits being poorly made. Or atleast certain components anyway.

Edit: Try moving the spring to the rear of the pump plate and putting another on the bottom guide rod.

[need4reebs]

yeah i thought it appeared nose down as well…but from only one pic its hard to tell? but that pump rod shouldn't look/be like that and would be my first guess for binding.

[BLachance75]

Let me know if you're interested in selling the hitman

[dboggs79]

I would guess not since he said it seemed to work fine using the pump handle. I'm guessing the hitman handle is producing enough leverage to bind what appears to be a sloppy kit.

[river031403]

Link to original sales thread

http://www.automags.org/forums/showthread.php?268072-FST-All-Black-ULE-PumpMag!!!!&p=2857128#post2857128

[river031403]

And most recent shooting video

http://youtu.be/XR7s30tpJCk

[need4reebs]

definitely a sloppy kit…from tha pump rod to tha hit man kit to tha pump plate to tha guide rods to tha pump handle.

[robertreed711]

And most recent shooting video
http://youtu.be/XR7s30tpJCk

Yes, this is exactly how it functions, a very short smooth stroke when using the pump handle.

I have read that the binding was common with these kit and that rainman has a remedy for it. I have contacted him on MCB and will see what he has to say.

http://www.automags.org/forums/showthread.php?260502-Rainman-Pump-Kit-Binding

[OPBN]

If it's a stock AGD milled rail his solution is going to be have it milled deeper. I'm his own words this kit is not milled to AGD specs and he doesn't guarantee it to work with any bodies or rails not milled by him. I had mine on a factory milled rail and it bound as well. Put it on another 3rd party milled rail and it works better. Still not as smooth as my AGD or XM15 kit. I always thought part of the problem was the mounting plate did not sit flush with the rail due to improperly milled angle.

[robertreed711]

If it's a stock AGD milled rail his solution is going to be have it milled deeper. I'm his own words this kit is not milled to AGD specs and he doesn't guarantee it to work with any bodies or rails not milled by him. I had mine on a factory milled rail and it bound as well. Put it on another 3rd party milled rail and it works better. Still not as smooth as my AGD or XM15 kit. I always thought part of the problem was the mounting plate did not sit flush with the rail due to improperly milled angle.

He may claim this but from what I can tell the problem is actually that the pump plate tips when using the hitman mod forcing it to bind on the center guide rod.

[captian pinky]

i have tried to warn everyone about the gen 3 kits. some people say theres are fine others say they are crap.

i was one of the original buyers of the gen 3 kits and i sent mine back to rainman to get multiple issues fixed and he said he didn't have a kit that met my expectations and refunded my money.