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Stemple Takedown Gun (STG) U9 Slow Fire (SF) - Adjustable Bolt System


Product Description


In 2003, the original inventor, John Stemple collaborated with BRP Corp to make new and replacement parts for the Stemple 76/45 receivers he manufactured prior to the 1986 cutoff.  From this came a series of compatible drop-on parts for the unmodified/transferable Stemple 76/45 receivers known as Stemple Takedown Gun (STG) setups.  Since nothing is welded or hand fitted to these receivers, changing setups and replacing parts is fast and easy.  These are the most finely built and smooth running sub-machine guns on the transferable market.  We build them for performance and durability, stock plenty of high-quality spare parts, and provide excellent service.  


U9 Slow Fire (SF) - Heavy Bolt System

The Slow Fire (SF) utilizes an ultra-smooth adjustable-weight bolt system with hydraulic buffering to dissipate the energy in the recoiling mass during the cycle process.  This is an ideal system for shooters looking to maximize suppressor performance by increasing dwell time in the chamber thereby reducing port noise. The cyclic rates with this system are adjustable between 525 to 900 round per minute.  Shooters can customize their preferred rates simply by adjusting the bolt parts.  At the lowest rate, this gun has a sustained fire of approximately 9 seconds with a 70-rd drum.   The Heavy Bolt System is also used for the 45ACP and 7.62x25 setups. These setups utilize AR pattern stocks, AR pattern grips, and multiple Picatinny mount options for maximum versatility


Parts and Accessories Included With Each Gun:  foregrip, bipod, 2 drums, 1 magazine, multi-tool, spare buffer, barrel locknut/muzzle cap tool, choice of barrel and shroud setup  (sights not included) 


Simple / Durable Design:

Our guns are very difficult to break and very easy to fix. They are simple blow-back guns and very smooth-running in long full-auto bursts. Some of our customers who own the 9mm guns liken the full-auto performance to a laser beam.

Takes standard AR grips, Ace pattern & AR pattern stocks, as well as a variety of shroud, barrel, & mounting options.

Easy-to-Replace Parts:
There's nothing on these guns that cant be easily replaced. We designed this system to protect the registered receiver from any wear during use. The only parts that can wear can be easily replaced without the need to ship the gun back-and-forth.

Available Service:
If you need service, we are here to support our products.

Shoot Cheap Ammo:
We typically just shoot steel-cased ammo. Our milled steel trunions easily deal with potential wear issues from any type of ammo.

Capacity and Control:  These guns use 70 round drums and are smooth cycling, heavy, accurate, and comfortable to hold.  It's basically an assault rifle with a sub-caliber setup... a very controllable and accurate gun in full auto.  It's so smooth due to the weight, layout, and action; you can actually watch your target being hit through a 4x scope while shooting long bursts.  The 'laser beam' performance of this gun makes is one of the most enjoyable full auto guns you'll ever shoot.

Can't Get Too Hot:  These are ideal for machine-gun shoots. The low-pressure pistol ammo cannot create enough heat in the barrel to cause a malfunction or damage the gun.  There's no gas system to clog, and the open-bolt system negates any cook-off risk.



Select-Fire with Quick-Change Barrel
Caliber:   9mm
Weight: 8 lbs with MN shroud/barrel, 9.7 lbs with Suomi M31 shroud/barrel
Magazine: Suomi KP31 25 rd, 36 rd, 50 rd magazines and 40 rd & 70 rd drums

(sights not included)



Product Videos

Stemple U9 Slow Fire 5 14 2015 (01:13)
Machine gunner in this video is competitive shooter Emily Nichole. Instagram: Emily_nichole_6
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