Custom HVLP BSA Scorpion SE .25 in Break Down stock

[Motorhead]

HVLP ( high volume low pressure ) such as many paintball markers use      This was an experiment to see what sort of power one could get running on very low pressure.   This gun was a Brand new gun I recently purchased minus the stock.  * So my intent here was to build a ONE OFF Custom using BSA parts and pieces from other current Scorpion based models and modify the entirety of the pneumatic system to run at low pressure using a BSA "Gold Star" regulator which is set at 70 bar ( @ 1050 psi ).

As we go down the pictures you will see a standard "SE" version gauge manifold that by design has some volume behind gauge and in front of valve.  * ADDED to this is the "Gold Star" regulator and it's plenum chamber screwed into where the HP cylinder typically fits.  Then the HP cylinder attached to the regulator.  This gave the gun a LOT of plenum volume which will be required and wanted running on lower pressure.

Internally the entirety of the pneumatic system was modified. larger .250" throat in valve with PEEK poppet, 5 mm transfer path all the way to barrel with probe also being to 5mm specs.   Barrel on these .25 bsa's is 18" so it got a custom full thin wall SS shroud assembly.

Hammer stroke was altered as was the hammer weight reduced with an added SSG devise to kill any hammer bounce.  All in all a full tip to tail reworking to optimize the breathing for a LP and modest power tune.

SO ... how does it shoot running on just 70 bar      JSB kings 725 fps making 30 ft lbs !!     It's no cannon but darn surprised myself it is making more than enough power for 50 yard and under pesting or play 

[Motorhead]

Next came the Synthetic stock that was modified to be EITHER a pistol or rifle and is plug in and secured or not   Aligned and epoxied in pins w/ o-rings hold it from falling off and a quick clasp at the bottome secures it when attached.
Completed gun in all it unique glory ...  ;
Make for one heck of a back porch or truck gun.  It is hefty too and inspit the slim lines its weight helps the muzzle flip shooting 25 grain pellets ... WOOF

PS. This build was done as an experiment with intent of selling it once completed .... will be listing it in the classified section in the near future.

Scott S

[YEMX]

Very Impressive work!!  I always wondered if a HVLP set up could be possible and give good power in .25! 

[Hobbyman2007]

Nice work Scott. I’ve played around with low pressure before in a Disco and shot unregulated filled to 1500psi in .22 . I’m liking low power tunes lately . Low power bullet shooting is really fun . I say low power , 50 FPE in .22 . Hahaha

[JimmyD.]

Great idea. I see fill pressures getting higher. More shots, more chances of leaks also.
So nobody wants long barrels but what did they use long ago? Wasn’t it 800psi? Maybe 1800. But it wasn’t no 2-5K
I wish I had your knowledge & shop Scott. You’re a real genius in all you undertake.

[Motorhead]

Well ... went and did it ... figured out how to get inside the Goldstar regulator and raise the set point, played with pressure and SSG spring.  Made a BALANCED poppet / chamber assembly to fit inside the factory valve body while staying with a very light hammer w/o the oem weights. 6# hammer spring has it Easy to cock too.
On a 2k set point we're making @ 43 fpe shooting 25.4 Kings @ 875 fps.

Now we have a short & stout CARBINE in .25 cal that is making some very good power.  While not a lot of shots looking like @ 20-22 on a 230 bar fill it makes for a perfect Truck gun .. Shop gun .. Yard critter blaster !