Conceptualizing my own version of Automag Pump Kit

[Rainmaker]

Hey fella's

I got out my classic mag the other day, and got the bug to make it a pump.
So i'm working through the design a bit, still just in the CAD stages.

I've got two 10-24 screws up top, riding in brass sleeves.
And a 1/4" stainless rod with a return spring riding in the lower brass tube.
Pump handle is a la PUCKer Up style at the moment.

Anyway, looking for any input, much appreciated!

[Spider!]

Be careful of too many guide rods. They quit helping at some point, depending on your tolerances

[Rainmaker]

That's good to know!

[alpha_q_up]

While I think I understand your use of 3 rods, I really think it's not necessary. Personally I think 1 is perfect if you can get away with it and 2 is the max needed for mag pump kits anything more than that feels kinda like overkill. The brass sleeve is a nice touch to give smother stroke but could the same be achieved with a nylon tube(I think that's what slice kits use), I've modded a Slice handle for a pump mag I have and that inner tube sliding on aluminum is money.

[Funsi00]

Looking forward to seeing a working prototype video!

[NONOBLITUS]

Watching and waiting to see this come to life.

[rawbutter]

Love the idea. Hope you have fun.

Here's a random thought. Has anyone ever used a square guide rod? Obviously that would have been really hard or impossible to do back before the 3D printing days, but now it seems easy. Then you wouldn't need 2 rods to prevent rolling the handle.

[Spider!]

Definitely there have been flat sided oval guides like the original pump mag which is a similar concept. Probably came out of stabbing an end mill into the handle and traveling over a diameter.

[Chemical-x.....ahain]

just reaching out to see if you are familiar with the stock pump mag hardware? the original guide rod is somewhat capsule shaped in profile; this helps to prevent twisting and is a streamlined solution. I'm not suggesting or directing, just tossing out an option as one of my favorite things on this forum is the problem solving, I see and the way we either engineer out the issue before the start or how we overcome a roadblock. I'm excited to see where this project takes you my friend.

[Rainmaker]

this is an important detail i know i need to capture - the shape of the pump rod. Probably need to get an existing kit for myself so i can replicate

[BLachance75]

The pump stroke is so short that you don’t need a guide rod. My XM-15 kit doesn’t have one and I’ve never thought it needed one.

[Rainmaker]

about how long is the pump stroke, like 1/2"?

[BLachance75]

Less than 1/2”, around 7/16 maybe a hair less

[Rainmaker]

Changed it up a little

[StaticShocked]

Oh, sneaky. I like how you hid the shoulder bolt!

[Rainmaker]

StaticShocked We'll see how it goes! The shoulder bolt will end up being captive by the brass tube when I press it in, or at least that's the plan. And the set screw in front will give access to tighten the bolt.

[Rainmaker]

Purchased some parts from McMaster. Including the wave spring. Printed a couple little sections of the handle and block to check the press fit of the brass sleeves. Adjusted and now the parts are printing.

[Chemical-x.....ahain]

Top notch, Im eager to see your project!!!

[Rainmaker]

Print done!

[Cal440]

That looks great!

[NONOBLITUS]

Ok standing in line with my pump milled rail.

[Rainmaker]

I think what I’m going to need is a couple volunteers who would be willing to install and play with a kit on their mag, I just don’t really get out enough to put it through its paces. Also I’ve only got one wave spring. Any of you guys play with your pump mag regularly?

[Chemical-x.....ahain]

quite saucy. can I ask what modeling software you use. Im running onshape and while I know doing a pattern is possible, i really need to look into how its done.

[Rainmaker]

@chemical-x-ahain I use Fusion 360 normally. I actually modeled this one in Inventor though. Both of those are great at making patterns, very intuitive. Onshape is a great tool, and I've used it in a pinch, but definitely prefer Fusion.