Pump action PCP?

[stoutblock]

I would want a pump action air rifle to handle and feel as much like a model 61 as possible.

It could be simplified by using a hammerless system so that the pump action was just to load the slugs from the tube to the breach. I assume it would be a slug only rifle as the action would probably damage pellets?

I would put the reservoir, fill gauge, power plenum, regulator and valve in the butt stock in a similar arrangement as the L2.

I would cover the barrel and ammo tube inside of an integrated shroud/moderator. I would shape the shroud cross section similar to the standard L2 shroud with a larger radius on the top than the bottom. The slide action would also be integrated into the shroud.

The tube would be removed from the front to load the slugs. I would make sure the tube would be able to load enough ammo to correlate with the reservoir volume. ~25-28 rounds of .22 with 170-200cc @300BAR.

Although a larger reservoir would be nice I don’t know how you could integrate it without ruining the sleek shape of a model 61? Since it would take a few minutes to reload a tube with slugs, you might as well just carry a small tank for refills?

 

[steve123]

Great initial design!

Aesthetically an idea I see to improve it is spitting a "fulled sized" rear stock along its length from front to rear to cover up "all" the metal from the receiver to butt pad and improvising a system hold them together to hide the screws when the gun is viewed sideways. and

Also putting the gauge on the rear of the tube. Doing this would clean up the appearance a lot.

I like the idea of having one fill for the amount of ammo in the tube. When empty you know its time to fill and for most hunters they wouldn't use all the ammo in the gun for the whole outing.
Otherwise when plinking that's the small price one pays for a handy little gun.

 

[stoutblock]

Great initial design!

Aesthetically an idea I see to improve it is spitting a "fulled sized" rear stock along its length from front to rear to cover up "all" the metal from the receiver to butt pad and improvising a system hold them together to hide the screws when the gun is viewed sideways. and

Also putting the gauge on the rear of the tube. Doing this would clean up the appearance a lot.

I like the idea of having one fill for the amount of ammo in the tube. When empty you know its time to fill and for most hunters they wouldn't use all the ammo in the gun for the whole outing.
Otherwise when plinking that's the small price one pays for a handy little gun.

It’s a fine line between aesthetics, feel and functionality. Maybe it’s because I spent so much time with one in my youth but I feel the model 61 has about the most perfect feel of any rifle ever made. It is light, well balanced, quick to shoulder and a very instinctual pointer.

I would try to keep the rear stock as thin as possible like the original while still able to retain the pressure side of the rifle. Even with the L2 type components partially enclosed in the rear stock it would still be thicker than a stock model 61. I’m sure I could cover it more but it would add thickness in locations that are not critical to the feel of the rifle.

I think it is important for the cheek rest to be seamless on top and for the grip area to be as true to the model 61 as possible. The illustration shows where I would split the stock as it would certainly need to be segmented for assembly and teardown. Agree all fasteners for these segments should be as hidden as possible.

I based the pressure side on the L2 which locates the fill pressure on the butt and the regulator pressure in the plenum which is where I show the regulated pressure gage. Totally agree it is not an ideal location as I am well aware because I own an L2. The REPR adjustment is on the other side but flush. If you were left handed this gage location would be unacceptable but you can turn the plenum on the L2 to switch the gage and REPR adjustment to the other side. The good news is the gage could be easily removable once a gun is tuned to your liking.

 

[stoutblock]

Basic concept for the pump action using a vertically translated breech activated by a guide pin running in a ramped slot. The concept is intended to minimize the space needed for the action in order to be contained by the slim model 61 receiver. Breech would have an adjustment screw (with center hole for air) to finetune for slug length. This fine tuning is critical because once the slug is loaded in the breech it would have to physically restrain the next round from interring the breech until translated vertically. The breech block would be temporarily removed from the bottom of the receiver to make this adjustment so it is not something you would want to do often. Action would clearly be sensitive to ammo size and shape. Perhaps flat nosed slugs would be needed? Once you had a slug working with this rifle you would not want to change products often!

 

[John "spysir" Blount]

Didnt everyone buy a Shark 20 shot pump? Someone needs to import these but it seems no on but Sunshine airguns could ever arrange it. Originally a bulk fill Co2 rig, simply screw an inverted paintball bottle for a few seconds & unscrew. Fired .22 Lobo round and actually grouped very well with the you could also single load pellets. These day's they are PCP rather then Co2.
Everyone who ever fired it had fun! And with round ball would put Squirrel on the table.

John