just THROWING this out there...
why cant we make a pnue-pump that when pumped, trips the trigger frames saftey off?
or make it fully pnue and only let the air to the ram after cocked?
or even an electronic pump handle that lets air through a noid
with that you could have a pump that with the flick of switch be pump OR semi!!!!!!!!!!!!!!!!
first ever
~crunch~
~crunch~
mq pumps aren't practical either its like taking a sniper pulling the fully working frame and internals out to spend easy $300 to do the same thing which end sup causing more headaches.
So thinking about the "block sear return" design, here's what I think needs to be resolved. Either:
1. Pump arm needs to reliably disengage from the sear block so it can't simply be held back and the marker is semi-auto again.
or
2. Sear travel is blocked by the mechanical "or" of the pump arm AND the blocking plate that's left behind.
I.e. In order to fire, the pump rod needs to go back forward AND the plate has to have been reset.
I think #2 is more feasible.
I was also playing around with this idea for the blocking plate:
Actually, I think I figured it out.
Last edited by GoatBoy; 04-10-2013 at 08:11 PM.
"Accuracy by aiming."
Definitely not on the A-Team.
Sat down and drew up what I was thinking.
The two sliding plates are spring loaded; the back one wants to rotate forward, the front one wants to rotate backwards.
State 1: Back of sear has dropped into the back plate's channel, front plate is held forward by pump rod and the front of sear is free to drop into channel.
State 2: Gun is fired, back of sear raises up out of back plate's channel. When it does, the spring loaded plate moves forward and prevents the sear from dropping down again.
State 3a: Pump rod is actuated backwards, which pushes the back plate back.
State 3b: As soon as the back plate is back far enough, the sear drops into the channel, locking the back plate. Front plate disengages from the sear and rotates backwards, preventing the sear from being able to drop (i.e. safety).
Pump arm moving forward returns to State 1, where the sear is free to drop into the front channel again.
There are various details like the non-orthogonal shape of the sear, but I believe they can all be worked out.
The benefit is: you still get to use all your fruity artistic custom bodies without modding, and your level 10 without modding.
However, the drawback is it's a pretty rail intensive mod. All the magic happens inside the rail, and if you want to get down to the nitty gritty, I think the pump rod and the rotation pins for the plates are outside of the 1" width of the rail if you want a full 0.68" pump stroke. So this might not even be able to be retrofitted on any existing rails.
Of course, if you have a 3d printed rail, the rail mod is cake.
Interesting concepts but this all falls way outside the KISS principal. Simplicity of operation is the main reason I love the current pump mag design
I know it isn't easy to Auto trigger/ slam fire a pump mag, but increasing ROF at the expense of accuracy defeats (for me) the point of shooting pump in the first place
Agreed. A spring loaded blocking plate/rod in the rail would actually be less complex than the current design. No need for a wave spring, body milling, or cutting down the spring. That latch is already there in the form of the sear. When the marker if fired the sear releases both the bolt and the blocking plate while switching the on off to the off position. The bolt is free to travel all the way back, but we are still not in semi because the plate prevents recharge via the on/off. Pulling the pump arm pushes the blocking plate back, the sear grabs it and the bolt and the on off returns to on.
The whole thing can be contained within the rail. You would have a plug and play "pump rail" much less complex than a pump rail, pump milled body, wave spring, cut spring, and all the tuning that goes along with it.
No violation of KISS.
In the drawing here I have added a second pump rod. The channels for the rods would actually be tunnels in this design. This lets us put o-rings on the pump rods so they can to double duty as stabilizing rods. Does not get much more simple than this.
"Everything should be made as simple as possible -- but no simpler."
I'm having difficulty visualizing the states in your picture.
How do you:
1. Guarantee 0.68" pump travel to reset the state?
2. Prevent the user from just holding the pump rod back and having full-time semi-auto?
This is basically a state machine with some required transitions.
Last edited by GoatBoy; 04-17-2013 at 11:17 AM.
1. No idea. I have no tools at my disposal to measure that kind of stuff. My off the cuff response would be to make the plate throw.68"
2. Missed that in this concept but easily rectified. Ad a secondary blocking device bridging the two rods. This would obstruct the sear while held back.
Scratch that. That will keep the sear from latching the first blocking plate. Need to think a bit.
Sit down, draw the state machine and required transitions and make sure you hit them all and that the state can't change outside the defined sequence.
You need some sort of latch mechanism. Your plate version will work if you can get it to latch back at a certain state, and spring out only after firing and stay out until reset by the pump. But there goes all your mechanical simplicity. I'm sure it can be done, but my version tries to use the existing available facilities with as few parts as possible, and without modification to the body.
simple question. can we put a powerful magnet or a spring in the grip to prevent the sear from comming back forward and then a pump arm that pushed the sear back intoplace by using the esisting slope on the front as a ramp
then make a spring loaded do hickey that catches the sear in the grip after it passes it. ever loosen a spring too much in an autoresponse frame?
U R techno-literate!
There's a reason why I rendered 4 different pictures and labeled the states. You have a very long, random road ahead of you if you don't get everything mapped out.
The rod on the back of the pump arms will work if they are spring loaded and retract in and out of the pump rods, which is actually kind of a neat idea. That's actually probably going to be a much simpler mechanism to implement on that back end.
It's just another implementation of what I did with the spring loaded plate. And thinking things through, I think I have some simplifications that can be made.
The magnet idea is interesting by the way.
Last edited by GoatBoy; 04-17-2013 at 01:43 PM.
someone with an emag magnet, open up their grip and see if a magnet will hold the sear back after fired. maybe 2
if it works then a magnet pump kit would be SOOO easy
Last edited by BTAutoMag; 04-17-2013 at 02:12 PM.
We'll have to test with different input pressures and On/Off assemblies of course.
true, I have a couple magnets and a ULTed xvalve, I can give my setup a shot
This should be a possibility. I was looking at different high strength magnets. With the RT on/off rated at about 4 lbs, I think you would have to put a target on the sear to hold it. The ULT should be about a lb and easier to work with. Perhaps using the catch magnet as a sear stop would help with a ULT in classic valve. A G-Force-ish extension would help with the RT on/off, as much as I hate to think it.
Still, the pump stroke will be a small kick to the sear. By the time you make something to stretch that stroke out, I'm thinking you might as well have a mechanical latch.
The magnet thing is where I liked a lever action, since the lever stroke wouldn't really work well with your finger on the trigger and the lever hanging down all the time. With a short pump stroke, you can always ride it in close to the activation point.
Last edited by Spider-TW; 04-17-2013 at 03:27 PM.