Dissecting a 1999 Mini STO Breakdown – serial 5759

WGP 99 Mini STO Minicocker Breakdown

Last year I picked this Minicocker up locally with the intension of keeping it for my collection. The serial number is 5759. It came with a Tippmann 98 and a nice green olive unique pack.

Ding in side of body on 99 Mini STO.
Ding in side of body on 99 Mini STO.

Unfortunately the unsightly dings on the right side changed my mind.

Right side view 99 Mini STO body.
Right side view 99 Mini STO body.

After getting multiple requests to sell the body I gave in, but decided to keep most of the stock parts and document the breakdown so I could eventually find another body to put the pieces back together on.

99 Mini STO engraved logo.
99 Mini STO engraved logo.

The parts I could identify as unique to this Mini STO were the valve, hammer, switch, bolt, p block, ram, ivg, and barrel.

1999 Mini STO Autococker STO Valve

The valve features only one side cut out with a solid base to lock the allen screw against.

1999 Mini STO autococker STO Hammer

The hammer has the front edge slightly beveled. The hammer looks like hardened steel and the front edge, where it strikes the valve is indented to increase the amount of time very slightly that the hammer is moving but keep the same mass. I mentioned the threads are 1/8th x 24 for modern lugs.

Belsales or WGP STO 3 way switch from 99 Mini STO Autococker

The switch uses the smaller 3×56 barbs with tight spacing, first used by Russell Breeden of RKB Engineering and later used by ANS, Shocktech, Dye and Belsales. The stock switch on the Minicocker was likely machined by WGP for Belsales and sold by Belsales.

The bolt is a more compact P Block bolt, to fit the 99 Mini STO’s P Block body.

1999 Mini STO Autococker non serialized back block

The P Block itself is similar to what came on most STOs of this period, but is not stamped with the last two digits of the serial, which early STOs featured.

Inner view of P block. No stamped serial number.
Inner view of P block. No stamped serial number.

Here is the inside view of the P block.

Outer view of P block, recessed at area that pushes cocking rod. Block base thickness is same as standard slanted 9 block.
Outer view of P block, recessed at area that pushes cocking rod. Block base thickness is same as standard slanted 9 block.

And the outside view.

99 Mini STO with serial 5759.
99 Mini STO with serial 5759.

The Ram features the flat front edge, which I believe is identical to the Shocktech Rams. The Shocktech rams were possibly manufactured by WGP and sold as Shocktech parts?

Inner back view of 99 Mini STO showing threads in lower tube.
Inner back view of 99 Mini STO showing threads in lower tube.

The IVG is the standard 3/16 adjuster screw style but is either plated brass or stainless. The majority I’ve seen from WGP are brass so I thought it was unusual to see a plated or stainless adjuster.

WGP STO barrel from a 1998 STO Minicocker.
WGP STO barrel from a 1998 STO Minicocker.

The barrel is a WGP branded J & J barrel.

Engraved tip on a WGP STO barrel from 1998.
Engraved tip on a WGP STO barrel from 1998.

 I listed this on the site a few months back.

Left side view 99 Mini STO body.
Left side view 99 Mini STO body.

This body also featured a plated brass detent.

Find the previous article on this 1999 Mini STO Cocker here.

And find more Autococker articles at.

And more Autococker parts on the site here.

LEAVE A REPLY

Please enter your comment!
Please enter your name here

A Minicocker similar to early BBT SFLs

Here is a tiny Minicocker I found that has some similarities to an early gen SFL autocockers. Really bad shape but neat round cuts.

Paintball Tek shoots a Kapp Razorback Autococker

Tim @ Paintball Tek dot come shoots a KAPP Razorback Autococker in his back year. The Splash on this Razorback is just amazing and it shoots great as well.

A KAPP Pre Razorback Autococker

A neat Kapp Autococker similar to a Razorback I found on craigslist.

Line SI Wire Stocks and Welded Feedneck 1987 Bushmasters

A look at two Wire Stocks on Line SI Bushmaster pump paintguns and some insight into the early Welded feedneck Skimrish / Line SI Bushmasters.

Adam Gardner, GWS Reno 1993 and the Smart Remote…

Is the Smart Remote Adam Gardner used in the Great Western Series Reno 1993 event the same as the remote I picked up last week?