Product Options Variations

With the almost endless options available for our firearms, it can be difficult at times to know what particular option is best for you. Below we have an in-depth discussion of each option available for our products. If you have an option or idea not discussed below, or would still like more information about a particular item, please do not hesitate to call or write us; we are more than happy to discuss them at length.

On each product page, you will see two groups of options;

product screen shot

The first group are options specific to that particular firearm. The second group are options and add on’s common to all of our firearms.


Weld Finish

We are the only company in the Roller-lock industry that can offer the weldless finish.

This is done by over-welding the bead, then painstakingly removing the additional material until it is flush with the parent metal. This is done in a manner that never removes any of the surrounding material, so no weakness is introduced into the seem. This results in a better looking product, but also results in a stronger weld, by removing the stress concentrations that a typical weld creates. A detailed explanation is very technical, but we are more than happy to go over the specifics if you would like.


A regular “exposed” weld finish is also available, which is similar to what would be seen on a Heckler & Koch produced product. However, our welds are not done in a mass-produced fashion or with any automation. This results in a cleaner and better weld than would ever be witnessed on a production firearm. NOTE: Welds on the rear sight base and installed rail (if applicable) will not be blended into the finish. Their location on the gun makes it impossible to do so without damaging the receiver.

Hand Guard

The hand guard for each firearm can be easily changed either by a push pin or Allen screw depending on the hand guard. The original firearms came with the appropriate sized polymer hand guard, a few examples are shown below:


The other no cost option is the aluminum hand guard.

Picture 116

They have a slimmer profile than the polymer models, and also are pre-tapped to attach picatinny rail sections for use of forward grips, lights etc.


Two other popular options available are the light weight models, available in both M-Lok and Keymod. In addition to their mounting interfaces, they are approximately 20% lighter than the original polymer options.

There are countless other hand guard offerings; polymer models with integrated lights, vented polymer, quad rail
picatinny mounts, and countless other options. Please contact us if you have something else in mind. gunwithlight

*Exception: The BASD model has a hand guard welded to the receiver, and can not be changed.

Cerakote Color

We use a certified Cerakote applicator, and only use the H(oven cured) that results in a 9H pencil hardness, outstanding corrosion resistance, and less frictional resistance on the internals. Our standard offering is our own proprietary flat black blend, which has also has a reduced IR signature (left image.)


The other Standard option is a higher luster black, resembling the painted finish found on the original German models (right image). It is a subtle difference not easily shown by photograph, but is very noticeable in person. If you want your gun to look as close to the original German models as possible, the semi-gloss finish is the closest match to the Epoxy paint originally used by Heckler & Koch.


In addition, we will also do any standard Cerakote color for free. Take a look at their website, Cerakote colors / for all their offerings.

We can also do any custom scheme you desire, just let us know what you would like and we will get you a quote.We normally do not coat the trigger housing, handguard, rear sight, or stock / endcap, but can at your request.


Picatinny Rail
We produce our own rail sections, so they sit low enough on the gun to not hinder use of the iron sights. This allows the use of a variety of optics with the gun, without having to use a claw mount device on the receiver.


These devices vary greatly in cost and performance, but almost always pose considerable difficulty with maintaining zero of the optic. They are also taller than the welded rail option, can damage the finish of the gun, and in the event of over tightening, can cause permanent damage to the gun and effect reliability.

The front of the rail is rounded to minimize  chances of cutting your hand when charging the gun. A rubber ladder section can also be attached to provide greater protection.

image (8)

Our standard length leaves ample space to mount almost any optic and not endanger your hands, but any length and position can be specified.

The original German design does have tabs on sides of the receiver, as well as a tab to assist in mounting the aforementioned claw mounts.


Extended Magazine Release (EMR)

The EMR is a bolt on product that is installed on a previously installed paddle magazine release. It allows release of the magazine with the primary hand, which results in faster reload times. It will work on any gun with a paddle magazine release, the 10mm and 40S&W models, as well as on UMP’s, G36’s and others. Its design also still allows access to the magazine release in the standard manner.


Trigger Group

The trigger pack houses the hammer, ejector, and fire control components for the roller lock platform.  The pack rests in a plastic housing, which attaches to the receiver of the gun. Our standard offering is a converted German pack with the markings “SEF” on one side, which is the German equivalent of safe, semi, and full auto.


Previously, if you wanted ambidextrous controls or the more popular “pictogram” style markings, an original HK model had to be converted, which resulted in an outrageous price increase of $500 due to availability, and their incompatibility with the SEF style internals.  We are now able to offer a reasonable solution. These trigger packs start out as SEF packs, and are then altered to utilize the ambidextrous selectors and appropriate housings. They are available in 2, 3 and 4 position styles (ALL MODELS ARE STILL SEMI-AUTO ONLY)

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Charging Handle 

All pistol caliber firearms, and some of the rifle calibers with straight pull back (discussed later) have the option of different charging handles. It is non-reciprocating on this platform, and can be used as a hand stop if so desired. the original designed featured a contoured profile to be pinched between the index and fore finger.

cocking handle

The other options are both aluminum, and provide a few extra millimeters for improved grip. the grooved profile (above) and straight profile (below) are both great improvements on the original design.


Exception: does not currently apply to .308 models

Sig Brace Adapter

For customers with disabilities, two Sig brace options are available. these replace the plastic end cap, and provide greater stability when used as a pistol. The SB93 was patterned to resemble the original fixed stock found on the German guns.


Trigger Upgrade

The Trigger group for these firearms is a robust, reliable, but very complicated ordeal. Due to this and the large scale of production they saw, the stock trigger pull is fairly gritty, has a lot of pre and post travel, and a pull weight around 12-15 lbs. Our trigger upgrade brings that pull weight down to a manageable 6-7 lbs, removes 90% of the creep and all of the grit. This is done without cutting springs or any other action that would reduce the reliability of the system.

Flip- Up Sight Upgrade

One of the design features that propelled this gun into the hearts of military and law enforcement professionals was the low height over bore, which resulted in a very accurate and predictable firearm. However, it does not allow for co-witness of the iron sights with almost any optic, and even when achieved, results in a very busy sight picture since one has to look through the front diopter sight. The flip up sight upgrade solves this by removing the front sight and replacing it with a picatinny rail section. The rear sight base is also removed, and a longer rail is put in its place. This allows the use of any number of flip up sights available on the market.

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Vortex Optics Package

This is our best solution for utilizing optics on this platform while still being able to use the iron sights. there are more expensive options on the market, but for all but the most abusive of environments, the Vortex SPARC II has proven to be more than capable. Included with the optic is a riser that has a window cut through it, allowing use of the iron sights. The SPARC II sits approximately 3″ over bore, which allows for a more relaxed position for faster engagements. Take a look at our other Knowledge Base article sight picture for more information.


Grip Stippling

Some have found the finish of the polymer grip housings to be a bit slippery; especially while wearing gloves or in inclement weather. the grip stippling upgrade solves this by laser etching a pattern on the front strap, back strap, and sides of the grip portion. IMG_2340IMG_2341

NFA Engraving

If you plan on submitting an ATF form 1 to convert your pistol into a Short Barreled Rifle (SBR,) either your personal or trust information must be engraved on the receiver. With this option we do the engraving for you at the factory, underneath the cerakote, so it does not have to be done and re-coated later. Having this engraving does not mandate you to file a form 1, if you choose not to you simply have a “name tag” on the firearm. Our standard engraving location is below the rear sight base.

sbr engraving


As witnessed above, there is a great deal of the design of this platform that is universal. However, there are some aspects specific to each gun, and are discussed below.

Barrel Length applies to 10mm and 40S&W models, and all Rifle Caliber models

This is fairly straight forward, and does not warrant much discussion. Contact us if you have specific questions regarding performance impact with different length barrels. Each Barrel length does include a cocking tube of the same length.

Straight Pull back applies to 5.56 and 300 AAC modelsIMG_6438

The rifle caliber models feature a levered cocking handle, in order to assist in overcoming the stronger locking mechanism required.  The straight pull back option, along with the extended charging handles described above, negate the need for a levering handle, and improve the ergonomics of the gun. At this time, we are not able to do the straight pull back option on other rifle calibers, but it is something we are pursuing.


Magazine applies to 5.56 and 300 AAC

Also fairly straight forward; allows use of AR magazines in place of the steel HK magazines.

steel mag

Magazine Release applies to all rifle caliber firearms, and all 9mm firearms

The original design featured a magazine release forward of the trigger module on the right side of the gun. This was very difficult to activate, so an additional magazine release was implemented behind the magazine.


Even with the paddle magazine release installed, the original magazine release button is retained. This paddle magazine release is pressed forward with the support hand. This is the standard option on all our firearms.

the other option is the Tac-Latch, which is also pressed with the support hand, but moves right as opposed to forward. Some may find it a more ergonomic motion. It is however not reversible (moving to the left) so lefties may find it difficult to use.


Magazine Sling Swivel applies to all 9mm firearms


An implementation by H&K for improved retention was placing an attachment point on the side of the magazine well. This was omitted on firearms designed later, as it was not used often, and had the possibility of getting caught on other equipment. We highly recommend removing this, unless you plan on using HK style slings on that location, as no other slings will interface with it.


Locking Piece applies to 40 S&W and 10mm models

the locking piece is the primary timing component for this platform. It dictates the dwell time between when a round is fired and when the bolt is able to extract the round and complete the rest of the firing cycle. Due to the characteristics of these specific calibers, two different locking pieces were design to improve reliability and lifespan of the system; one for low impulse rounds, and one for high impulse “hotter loaded ” rounds. Not using the correct locking piece for the corresponding ammunition will either result in poor functioning, or increased wear on the firearm. We recommend getting both; as they are fairly inexpensive and easy to change out.

A final option, though not listed, is worth mentioning. We are able to make firearms that comply with specific state firearms laws, including California and Maryland. There are variety of options and factors required with which to address this, so please contact us if you have any questions or require more information.

This is by no means an exhaustive list of our capabilities and available options. We are constantly developing new accessories, and have yet to have a custom configuration we couldn’t make; to include left handed models, custom barrel lengths, and even custom calibers. If you have any interest in something not listed, please feel free to contact us for more information.