RainMan pump kits!

[OPBN]

I don't have anything to go by as this is the only RM kit I have. I know that the stock AM kit that I have fits totally flush with the bottom of the rail and so does the XM15 kit. I did get a PM back from him saying that he thought the rail channel might be too narrow since his pump rod/arm whatever is thicker than the AGD one. I personally don't think that's it. When I pull the assembly apart and slide the pump arm in and out, it slides freely. As soon as I put everything together and snug up the front mounting screw it binds.

[luke]

OPBN, I'll pm you the info I believe he needs for the fix and you can pass it on to him.

[OPBN]

Being told that "this is how my kits have mounted from day 1". Not exactly the response I was hoping for.

[Levi]

Same issue here

[OPBN]

Same issue here

Is yours binding? If so, please contact him on MCB.

[Levi]

Is yours binding? If so, please contact him on MCB.

Unfortunately I have no way of knowing at this point, as none of my classic rails are pump milled. I was planning on doing that myself as soon as I get around to wiring up my mill... which probably wont be for a few more weeks. I'm a picky bastard, and having that gap there is going to bug me... I'll probably end up fixing it myself I guess.

[barkingspider]

Mine works with problems. It's actually pretty good and doesn't bind or hang up with a pump stroke. I put a little graphite in the milled channel and everything seems to stroke fairly smooth. When I assembled I took the pump handle off and loosed the screws in hopes that any malaligned parts would align with a few initial pump strokes.

I had Luke mill my rail awhile ago

[Levi]

I had Luke mill my rail awhile ago

Luke... do you mill the pump slot to AGD specs? Or do you open it up a little to make way for a beefier pump rod?

[luke]

AGD spec.

The correct rod 'material' is available if you know what and where to buy, 'perhaps' it's a mystery...


(EDIT #3)lol

[Levi]

AGD spec.

The correct rod 'material' is available if you know what and where to buy, 'perhaps' it's a mystery...

What diameter is the 'correct' material?

The pump rod that came with my kit measures in at 0.125"

[luke]

0.125" is not AGD spec.

[luke]

Material diameter should be 0.110"

[Levi]

Material diameter should be 0.110"

Thanks Luke!

[Levi]

I had a chance to examine this thing a little closer this morning. Just noticed that the mounting hole and slot are machined 0.020" off center

Notice how the slot cuts into the chamfer on one side but not on the other.





OPBN, from your pic it looks like yours may be the same way. It this perhaps contributing to the binding issue?

[OPBN]

I had a chance to examine this thing a little closer this morning. Just noticed that the mounting hole and slot are machined 0.020" off center

Notice how the slot cuts into the chamfer on one side but not on the other.

OPBN, from your pic it looks like yours may be the same way. It this perhaps contributing to the binding issue?

The closer I look, yes it does appear that it is very slightly off center. I will say that the milling for the pump arm does not appear to be as high up as yours either. There is no threading visible...