FSB builds with free float forends hold a special place in my heart. Let's see pics and details of your builds. Only parameters: build must be an AR variant, have an FSB and a free float forend (rail, tube, other; carbine length, mid-length, rifle length; cutout, non-cutout, whatever). Just share pics and some general specs. Try to keep the discussion limited to the builds displayed here.

Lot's of customization on this build and many parts will be easily identifiable from the photos. Some key items to call out are:

- Aero Upper Receiver
- 14.5" Daniel Defense CHF Gov Profile, Mid-length Barrel with their improved FSB design
- Pinned / Welded PWS FSC556
- Mid-length Centurion C4 Cutout Rail
- And, because I wish I was Swamp Thing, I run it with a Ranger Green Magpul sling (not pictured)





ETA - 7/9/17:
Made a few updates to my build: moved the RVG and handstop back a few notches, upgraded my WML and added a Steiner CQBL-1. This build feels complete, for now...





ETA - 10/15/18:
I could not leave well enough alone... I replaced the EXPS3-0 with an Aimpoint T2 on a Larue LT-660 mount. Also, I tried to reduce some forward heft by swapping out the CQBL-1 with a Laser Devices ITAL mounted on a Larue LT-271 mount. This is controlled by a Streamlight Dual Function tapeswitch that I modified to work with the laser. I'm digging the ergonomics of where this sits near my IR WML, as well as the fact that the clicky button gives me a "constant on" capability on a momentary only laser. Finally, my pride and joy... a new Tango Down QD stubby grip that I dyed to match my OD Green Magpul furniture. Way more comfortable than the RVG. It has the benefit of being able to remove on the fly, plus the additional battery storage (AAs in the K2+ grip core and CR123As in the Stubby).

We'll see how long this setup lasts, but for now, I'm in love again with my modern take on a timeless classic.







ETA - 6/9/20:
Well, it lasted just under three years, and I swear that I won't fuck with it anymore (yeah right), but here she is. The T2 lives elsewhere now, so I replaced it with a T1 with OD Tangodown cover. There may or may not have been a lower swap, as well, which now puts this build on my OIF-15 Iraq lower. I'm also back to MOE+ and MIAD grips now, instead of the K2+.

This is my modernized tribute to what I went to war with, only better. Daniel Defense barrels are accurate as shit.





I completed the below build nearly a year ago. Originally showcased on Page 12, this is my Futuristic RECCE. I had alot of fun with this one. It's definitely unlike anything else I've put together (let alone seen). I'm still tinkering with it to this day, but most recent updates involve switching back to the MIAD grip and the MOE Fixed Carbine stock. I've ditched all of my K2+ grips.

Upper:
- Aero upper receiver assembly
- 16" Daniel Defense midlength gov profile barrel (1:7)
- Ballistic Advantage melonited midlength gas tube
- A.R.M.S 41-B Silouette front sight gas block
- Primary Weapons System PWS FSC556 muzzle device
- Centurion Arms 14.25" CMR Rail with midlength FSB cutout
- Modified OD green CMR covers, handstop, and Magpul M-LOK MVG
- Arisaka CMR offset rail mount
- Inforce WMLx (IR version)
- Modified KAC M-LOK rail sections
- Harris/Larue BRM-S and LT706 QD Swivel Mount Combo with added KMW Pod-Loc
- Magpul MBUS Pro LR rear sight
- Larue SPR-E mount
- Steiner M5Xi scope
- Palmetto Premium BCG with Sprinco extra power extractor spring upgrade
- Radian Raptor charging handle

Lower:
- PSA Stealth lower and parts
- Larue MBT-2S trigger
- Radian Talon ambi safety
- OD green Magpul MIAD grip with battery storage
- IWC QD endplate
- Brownells 6 position buffer tube (milspec)
- Sprinco Blue Buffer spring
- Colt H buffer
- OD green Magpul Fixed Carbine stock
- Custom, ambidextrous/rotation limited QD cup insert kit for stock (Special shoutout to @MegaSexual who made these - Really smart design/superior to Magpul's version, which lacks the rotation limiting cuts)

I'm trying to figure out if I can do this on a 2A Armament 15 inch rail.

I don't see why not. If you have an FSB in the rifle length position, you'd just have to chop about 3" off the top rail. I suggest taking precise measurements first, though.

Build thread

Anderson lower
BCM LPK
ALG QMS trigger
BCM GF trigger guard
BCM GF Mod 0 grip
BCM GF end plate
BCM GF stock
BCM BT
H3 buffer
Springco Blue action spring

BCM upper receiver
Colt 14.5" M4 profile barrel
BCM extended A2 hider P&W (changing to an SEI Vortex)
BCM BCG
BCM Mod 4 CH
Centurion Arms C4 Carbine cutout
Magpul XTM rail panels and hand stop
Troy BUIS
Trijicon tritium front sight (possibly changing to the XS CSAT system)
Trijicon MRO with factory mount (changing mount to ADM mount)
Surefire Scout M600 SR02 dual switch
Gear Sector scout mount
Magpul MS4 sling in grey




I have a dizzy that I want to change the rail on. Right now it wears a KAC M5 RAS. I would like to put a FF rail. I am not sure if anyone makes a FF FSP rail. I was thinking about finding a 13" rail and cutting it to fit the front sight base. Just not sure which rail would work best.

Rifle in question.

Nice. How are you liking the MRO?

@Charlie_Foxtrot when you get around to switching out those rails and if you're looking to offload that KAC M5, I will probably be in the market for it. I have one more M16A4 clone I need to make next year.

I love my MRO. It took awhile for me to adopt one since I have Aimpoints I always figured what's the point. I bought this one and now I want to replace all of my Aimpoints with MROs. The MRO seems to be either you love it or hate it. I read about people complaining about reflections in the glass or a blue tint or the slight magnification bothering them. For me, those things haven't been an issue. There is a slight blue tint but not enough to matter to me, I haven't experienced any reflections in the glass and the magnification doesn't seem to effect my sight picture. If I had a concern it would be with the sight adjustment, they move very easily. I wish they were covered or capped. Though I haven't had any problems yet with the adjustments moving. Also it's ugly but that's okay.

@joshdb50 I'm not sure which direction I am going to go with it yet I might decide to build an A4 myself. That is still a clone I haven't done yet or I might put it on my A2. Like I said, not sure yet but I will keep you in mind if I do decide to sell it.

I'm weird with FSB's.  I like when there is a cutout at the front of the rail, such that the side/bottom continue to the front of the sight, but don't come back together in front of it.  However, I don't like the ones that come back together and continue as a full rail forward of the sight.  For example, I like the Mk18 FSB, but not the RIS II FSB.  Totally subjective and I can understand why somebody might like the latter; it's just not my thing.  Either way, though, I admire homemade ones that are done well.

Folks, the intention was to keep the discussions limited to the builds posted here. Let's see some pics and specs.

Midlength gas system.

My Block II:


- Standard upper receiver
- Colt 14.5 Socom barrel
- DD RIS II FSP
- Surefire Warcomp
- BCM Mod 4 CH
- Matech BUIS
- Tango Down VG
- B5 Stock and pistol grip
- PSA lower receiver
- PSA LPK
- ALG ACT triger
- BCG from Right to Bear (8620 carrier, Carpenter 158 bolt)
- TA33 Green horseshoe dot
- GDI R-Com E-Model mount

Nice. Your paint job came out great. Have you considered adding to the furniture, or do you prefer the contrast? It does seem to suit your environment. +1 for being the first RIS II.

Anyone out there have a DDM4 FSB Rail?

Basic 16" M4 type carbine build
CMMG nitride barrel
CMMG lpk
Spikes Tactical nitride BCG
Daniel Defense Omega 7.0 free float quad rail
Streamlight ProTac RM-1 tactical light in Thorntail Scout Mount offset right at 1:00 o'clock
Streamlight tape switch tail cap at 12 o'clock for ambi access
Leupold Deltapoint Pro in ADM QD mount
Magpul MBUS folded rear sight

Thanks!

I will likely cover everything at some point, all my other rifles are entirely painted. I am digging the contrast, for now .

This is my build.

Configuration one:





Configuration two:





CSAT aperture love:





As stated in previous thread, LT103 is my BUIS.  I prefer it to a flip-up.  To maintain iron sight proficiency I use it about 80% of the time I shoot and only shoot the TR24 for 20%.  By comparison the TR24 is cheating.

ETA: as per instructions for this thread, configuration is

Strike Industries FSP cutout megafins rail (may be the first such photo on this VERY under appreciated thread)
Spikes midlength CHF ELW upper
Noveske chainsaw lower
Spikes lower parts kit
ALG QMS trigger
BCM grip and handguard panels
Vltor A1 length ARM stock
TR24 (Green triangle)
Larue LT103
CSAT Aperture
KNS .034 FSP
GG&G 3 slot keymod rail (for mounting the LT103 when not in use)
Precision Armament EFAB
Surefire M300 scout
Impact weapons components mount-n-slot scout mount
VTAC sling with Proctor sling attachments

Nice. Any chance we can see the others? A bit repetative, I know, but might trigger some good ideas for the mainstream!

It'd be pretty boring.  It would just be a variation on my truck gun's theme: midlength, FSP cutout, fixed irons, 9 o'clock light.  Variable optics are planned for each gun and one is on order but for now my other guns are irons only.  With only a couple exceptions for specific guns that are for specific functions, my general use carbines are all the same so that my manipulation and controls are always familiar and intuitive.

I DO want to pin a Brevis II to a 14.5" that currently has a pinned A2x, but that won't happen for a while.

ETA:
@mhbaker81  Ah fuck it:


An older pic of a different FSP cutout build I have.  This build has evolved a little since then.  Another update when it is complete.

Attached File

BCM Kino
Saker K 556

I was going to post one but then read the middy part and it left me confused. Why does the OP think that there's a shirt that has what he is looking for?

Not trying to create confusion. It's quite simple actually: If you have an FSB Build with a free float forend/rail, then post. Gas length does not matter. Mine just happens to be a middy. I'm also fully stocked on shirts.

I took my RRA standard A2 20" with the 1/9 twist barrel and replaced it with a Windham 1/7 Chrome lined and replaced the standard forend with a KAC FF RAS.  I removed the FSB sling swivel and used a rail mounted one as a replacement.  Its a great rifle.  Its otherwise stock, no NM parts on it.  My plans have been to shoot with this rifle in Service Rifle matches until I can buy a NM upper or NM Rifle.

Almost all of my AR's have FF front rail, most with KAC RAS or DD (MK12 Mod 1, M4 carbine, MK18, DDM4 v1, etc.).

Kind of a shitty pic, but you get the idea.  I created a thread with Q&A about building/modifying my 20" upper for Service Rifle and then at the end there is a link to my build thread.  Starts here, more pics in the build thread.

ST LE 16" upper with a ST SAR rail added a few years later...

Simple? Why are you naming a gas length after a shirt, it's called a mid length. So yes, it is an actual confusion. So do you want a pic of a free float with FSB mid length, or of an infant or female's wearing a middy?

Colt 6920
Centurion Arms Carbine cutout rail
Aimpoint T-1 in Larue 660
Surefire M600U in Haley Thorntail Mount
DBal I2 I/R / Green
B5 Sopmod
MagPul Ms3
Troy BUIS
Magpul K2 grip
KAC VFG

Cool thread

Attached File

Awwww... Look up top (I changed it just for you.) I hope this provides enough comfort for you to now post your build and specs.

Here's the upper I built for someone else. It's a Lite Rail III/DDM4 9.0 rail modded into a FSP rail. It's a 5.56 with a 10.0" barrel. These rails were made to fit a carbine length FSB without bayonet lug or sling mount. I don't believe they will line up with a mid length FSB however. I encourage anyone who's building a rifle with a 9", 10", 12, or even a 15" rail with carbine FSB to pursue this mod.

Attached File


Attached File


Attached File


Attached File

Bump, would love to see more rifle length builds

What a special snowflake you are

Did you mill the rail or just assemble the upper?

Probably my favorite rifle.  Noveske CHF 14.5" barrel with Centurion C4 mid length cutout rail and pinned saker flash hider.

I am digging all the Centurion Arms love in this thread.  I'm a fan.

I cut it out with a Dremel and hand files and used a mill to drill the bottom holes. It wasn't hard, just time consuming since I did it mostly by hand. The bottom holes are already there on the longer rails.

I wish I could have found a centurion at a decent price but I settled for a casv for $125. It should work out pretty well since I'm moving my 2.5-10x32 vortex in warne qd rings off my. 308 bolt gun.

I don't have the rail yet but will post pics when I get it.

That looks excellent. This thread motivates me to FF my dizzy. I need to find a 13.5" or 14" rail I think.

In the middle of changing this rifle up but it sure looked good this way- 

Thanks. You'll need a ~12.5" rail to end right before the FSB or a ~15" rail if you are going to make a FSB cutout.

CC... Love it. Major points for being the first DDM4 12.0 FSP rail. Hit me up if you decide to change the rail. I would gladly take this one off your hands!

I keep trying to snag a used Centurion cutout rail on the EE for my 14.5 in lightweight carbine , so far no luck . Will probably break down and buy a new one soon .

I am with Old_Painless. Let's try to focus on pics and specs. Seeing some nice builds so far. Keep it up.

Attached File

Attached File

Attached File


14.5" Colt Socom with spacer & pinned A2

I need to jump on that list to get one of those cutout rails from Centurion. Looks sharp.

My humble 6920

Troy cutout? Looks good.

Easter day photo

Attached File

Thanks!

Unfortunately I just sold it in the EE last week. It was an awesome rail! Would definitely recommend.

I would buy one of those Knights FSP cutout rails just for the novelty.