French semi-automatic rifle

[-X3-]

Hi all, I'm here to show you my creation : it's a semi automatic pneumatic rifle with 15 shots charger.
The ammo is steel ball, 10mm diameter.
I shot at 15bar (215psi), and with 70cm long cannon the performances are quite impressive.
I have a paintball air tank, and I modded the regulator to have lower pressure (stock preset is 60bar)
Full view (old batteries placement)


Disassembling is easy, just remove the hand grip and unscrew. The whole cannon can be maintained




New batteries placement, and the suppressor in place


Suppressor :



Quick demonstration in my cave :
[youtube][/youtube]

[bravootome]

very nice looking piece you made there but by the sound it doent look pretty powerful ....it probably a good suspressor
it will fit well in a nice wood stock ....

[-X3-]

Yep the suppressor is quite effective. About the power, the steel ball bearings (4,5g) goes right through this MDF board (18mm thick).

[bravootome]

Yep the suppressor is quite effective. About the power, the steel ball bearings (4,5g) goes right through this MDF board (18mm thick).

I shoot 6mm, 0, 86 grams trough 18 mm board

[Brian the brain]

Performance could simply be improved by enlarging the chamber or upping the pressure.
Shortening the supressor might help aswell.
In that case I would use a bigger outer case to keep the volume up.

The design is what elevates this launcher above the average.

Very cool.

One question though: what slows down the action?
I bet the cycle rate could be increased..

Perhaps modding the QEV is an option for you, this doesn't hurt performance but lowers air consumption greatly...in turn upping potential cycle rate..

[-X3-]

Performance could simply be improved by enlarging the chamber or upping the pressure.
Shortening the supressor might help aswell.
In that case I would use a bigger outer case to keep the volume up.

I had a larger chamber before (about 50% more volume) but the performances were not better...
About upping the pressure, I am limited by the crappy distributor which normally holds only 10bar and started leaking at 12bar in the past...until I reinforced it !
Shortening the suppressor might not help beacause the internal tube is one size more than the ammo (12mm internal for 10mm ammos) so it doesn't slow the balls

The design is what elevates this launcher above the average.

Very cool.

Coming from you, I really take it as a compliment

One question though: what slows down the action?
I bet the cycle rate could be increased..

The cylinder is a bit slow, but I think most of the filling time is due to my distributor...air ports are really smalls

Perhaps modding the QEV is an option for you, this doesn't hurt performance but lowers air consumption greatly...in turn upping potential cycle rate..

Modding the QEV ? In which way ? I had a 1/2" QEV before on this launcher and reduced it to a 3/8" to limit air consumption (pilot volume)

[Brian the brain]

I wasn;t paying enough attention to how your system works...

A modded qev will close after the ammo has left the barrel but before the chamber is empty, saving air.
But your airram needs an empty chamber to reload the launcher.

You will need to hook up the airram to the barrel to benefit from a modded QEV.
I mean modifying it by drilling a very small hole in the piston between the sealing face and the outer edge.
Then put a weak spring behind the piston.

This will allow the QEV to be refilled from the chamberside, in other words it will close even with pressure in the chamber, once the pilot valve is closed.
It will mimic what the pilotvalve is doing, but with much bigger flow.

If you could get the airram to work with almost no friction, it will respond to the short blast of air from the barrel.
A one-way valve could make sure the airram gets enough umph to fully extend.

If you provide it with air through a Tee near the muzzle it could be made to quickly snap back with each shot, diverting air to the ram as the ammo passes the Tee.

Should make things respond much faster...but it'll take a lot of tinkering to get it working right.

[-X3-]

Ok, it seems a little tricky to adjust but I could use this in a new launcher...I'll see
I really like the actual design because of the reliability
I'm thinking about making a stock, but I'm not really fan of wood...maybe plastic/resin material and black paint.

[jackssmirkingrevenge]

très beau travail! I wager the suppressor will work better without the filling though.

[-X3-]

I will try without it, I'll let you know !
Thank you for the compliment !

[-X3-]

Okay, DP becaue I tried my silencer without any filling inside and it seems to be louder...
Anyway, I'm thiniking about making baffles now...
I had a larger suppressor before, filled with baffles and foam spacers. It was really effective but the outside diameter of 50mm was really ugly !