GBF (Gas Block, Forward Controls)

[Duffy]

GBF just dropped :)

https://www.forwardcontrolsdesign.com/GBF-_p_203.html

In development since 2018, GBF went through several design changes, culminating in its final design that incorporated many suggestions from users and armorers in mid 2019.

GBF isn't meant to be a light weight gas block. We removed material where it's simply dead weight, we wanted GBF to be small and slick, not for aesthetics reasons, its external shape could affect its hand guards compatibility.

GBF has bosses for barrel pinning, but no holes are drilled. Knurled set screws are included, so is a gas tube pin. Barrel pinning coiled pin can be added at no additional cost.

The late Semper Paratus Arms owner Will Larson is known to many of you. GBF was the last project Will had design input on, and we incorporated both into the production model:

1. Manganese phosphate instead of nitride. Will didn't believe the hard coating was conducive to providing every ounce of seal a gas block could.
2. 3/32 punch access port, forward of the gas tube, to allow a 3/32 punch to go through and dislodge a stuck gas tube.

GBF is machined in heat treated 4140 steel, and manganese phosphate coated.

[UWone77]

For Gas block pinning... brilliant Roger. Another winner

[Stone]

"Another useful feature is the bosses on both sides of the GBF to give gunsmiths an easy reference point to pin the GBF to the barrel"

Maybe its been a long day but where exactly do you drill at? If its at the lower angle on the boss the bit would just drift away(left,right or down) making it difficult to get the bit started...
Or even at the apex of the boss, its such a small area, again it seems it would be difficult to get a bit started.

[Duffy]

The area is identified by the bosses, which is relatively small, compared to gas blocks sans the bosses, you can literally drill it anywhere lol. The bosses are straight (12 o'clock to 6 o'clock), its horizontal plane is perpendicular to the bore, it's easier to drill on it than the sloped contour of the gas block itself :)

[Stone]

Thanks Roger, its a great design.

[Duffy]

It bears some resemblance to G's gas block. GBF as it was in 2018 looked vastly different than it does now, we didn't look at anyone else's design to avoid being swayed by them. The bosses were added later in the design process specifically for a 5/8 long pin for pinning the gas block to the barrel, so the geometry of the bosses/flats was dictated by the length of the pins we intend the users to use, and indeed we supply either diameter at no cost with the GBF. The size of the flat is just big enough to encompass a 5/32 x 5/8 pin's diameter. If the user opts to use a 1/8 pin, GBF can accommodate that as well.

[BoilerUp]

Why not pre-drill? Seems like that would be helpful.

[Stone]

Yeah, that would be cool. Even just an 1/8" deep or so to get the bit guided in the right direction. Not all the way through leaves the option for those that dont want to pin it...[pop]

[Duffy]

It would seem that way, the prototypes were pre drilled all the way through. We may incorporate a shallow witness mark in the next production run, thanks for the suggestion.

We make almost all of our products in small batches, it allows us to make changes quickly :)

[UWone77]

I don't think you need to drill them all the way through. Not too many DIY pinners, and if you're having your local smith do it, they'll have to drill the block and barrel anyway.

[mustangfreek]

No sense in predrilling, it should be done in a jig and then hole drilled.

Nice looking GB!