Tuesday, July 19, 2022

San Tan Tactical STT-15L Lightweight AR15 PILLAR Receiver Set

San Tan Tactical STT-15L Lightweight AR15 PILLAR Receiver Set

For those that exclusively scour the internet for the cheapest AR15 parts in existence to cobble together an AR15 build, this $470 San Tan Tactical SST-15 upper and lower set is probably not for you. On the other hand, if you appreciate a flawlessly made AR15 receiver set, loaded with well executed details and demand the best and don’t mind paying for quality then read on. This San Tan Tactical receiver set is the Bugatti Veyron or Chiron of the AR15 world.

Despite AR15s arguably outselling shampoo in the last few years, some companies are struggling to offer nothing more than clone ARs with a different logo. On the other side of that coin you see companies that are doing something different, setting a new bar for quality, features, and value and maybe even offering something we never knew we needed. Some are delivering great guns at an entry level and others like San Tan Tactical’s SST-15 AR15 Lower Receiver are dripping with sexy lines, precision, and features that set it apart from anything ordinary.

Before I jump into what makes the San Tan's billet receiver set special, let's wander through the red, white and blue Patriot AR15 build created based on this SST-15 receiver set. All in, this is about a $2100 build including optic which is in the range of an extremely well appointed and very accurate 3Gun rifle.

As I do with all builds, I started with truing the receiver. On quality receivers of this tier, I find it is not necessarily the billet milled aluminum that is not perfect, but actually the post machining anodizing which can need lapping to be perfectly square. I use the Brownells receiver lapping tool and compound and the process can net drastic accuracy improvements. The San Tan receiver only required a very quick touch of under a minute to square up.

Ballistic Advantage Hanson series stainless barrels are fantastic right out of the box, however I decided to do a little sanding and polishing work to bring the bead blasted 16” .223 Wylde Hanson barrel finish up to a semi-reflective luster. After a good 800-grit sanding and a few passes of Flitz polish, I was surprised how fast this process was.

HANDGUARD - If you have a barrel that is stunning, why hide it under a handguard, so the open and airy looking Odin O2 Lite Red freefloat handguard was used. Though the handguard looks delicate, it is structured to take the same abuse as any other handguard. Since we have a patriotic color theme going, I added a silver colored natural polished V7 titanium ejection port cover. A bit of copper anti-seize was used on the receiver thread and the Odin barrel nut assembly was timed and tightened to 50-ft/lbs.

GAS BLOCK & MUZZLE DEVICE - Since I had the plan to use a lightweight carrier, I installed a Superlative Arms adjustable gas block to deliver that nice light recoiling and flat shooting competition AR15 feel we all love. I hate extra noise just as much as anyone and decided to stick with one of the quietest muzzle devices made, a standard stainless steel Rousch Sports A2 style flash hider and crush washer. The SA adjustable gas block, lightweight carrier and A2 rifle length buffer drop the recoil to a point I don’t feel it's really necessary to also install a comp that will just require doubling ear pro.

To finish up the upper, a Faxon Ultra-Light bolt carrier, a design which has proven itself to me in many builds as a great quality carrier in a very light design. Geissele makes a lot of great products, but one of the great unsung products is the Geissele Super Charging Ambi-Handle used in this build.  

For the lower, I had a lot of parts looking for a great home including a Battle Arms Development Take-Down pins and bolt catch, Strike Industries selector, Geissele SD-3G - Super Dynamic 3Gun trigger, and KNS Anti-Rotate pins. A Magpul grip and rifle length Ace UL Stock were used to finish up the lower.  I also did a custom paracord wrap on the A2 tube.

OPTICS - There are certainly boatloads of fantastic optics now on the market which deliver outstanding clarity, broad 1-6 or more magnification and features like integrated throw handles, however I choose the Burris RT-6 for several reasons. First, the RT-6 for the price is a fantastic optic and from my perspective Burris hit is out of the park on a 3Gun worthy optic at a $360 price everyone can afford. Is it a $1000 Sig, Athelon, Eotech, or Vortex? No, but it is a damn great $500 optic for $360. My wife is likely going to shoot this gun and she has a RT-6 mounted on her other AR15 which she is familiar with. There was no reason to make the optics choice more expensive or complex if it didn’t need to be. Optics mounting was with an Aero scope mount delivering an elegant strong mount.

SanTan Tactical STT-15L Pillar Billet Receiver Combo - $429 - Mil-Spec is required on the battlefield, however not for the custom AR15 builder.  I have handled and tested just about every receiver set out there on the market and no one packs all the quality, fit, finish and features into billet 7075 aluminum like SanTan Tactical. On custom builds, it is good to see design details that will set the receiver apart from other builds. The STT-15L is their lightest set which drops the ambi-features on the lower, and omits the forward assist.

Each SST-15L set is milled from a solid chunk of 7075-T651 aerospace grade American aluminum milled on Haas CNC machinery which assures precision tolerances. Once milled, the finished receiver is then MIL-A-8625 Type III hard anodizing to assure the best corrosion resistant anodizing possible. 

The overall fit and finish is impeccable including the pitch black hard anodized receiver.  Stylistically, San Tan wanted to avoid the typical bulky billet look and instead develop an overall receiver that had a similar overall size as a forged lower.  Instead of a heavy extended magwell lip, they have created a huge funnel without adding much extra bulk and have worked hard to design a trim overall billet receiver set maximizing weight reduction.

The extended trigger guard is thin and contoured that actually flows into the grip instead of the unnecessarily thick .25” guards like I have seen some lowers. The San Tan Tactical SST-15 has been lightened and strengthened in key strategic areas to retain strength but minimize weight.  Ergonomics were enhanced with a lot of extra contouring and radiusing and mitering of angles to deliver a more comfortable fit in the shooters hand.  

And then comes the barrage of features. A huge magazine well, Shooter-Ready trigger finger rest just under the magazine release, oversized winter trigger guard, ambi-selector switch bullet pictograms, dowel/grub screws (no pins) assembly and extra grip on all the ambi releases. The non-ultralight models include integrated QD-Sling mounts on each side of the receiver with 45-degree anti-rotate stops, and integrated ambidextrous bolt and magazine releases.

If you are into higher end AR15s you are probably familiar with receiver tension screws and their ability to tighten up a worn or loose upper. San Tan has gone about it a little differently with a small nylon tipped screw that is barely noticeable looking into the receiver.  The tension can be adjusted via hex wrench after removing the grip. Also adjustable while the grip is off is the unique trigger over-travel adjustment which can make an OK stock trigger feel pretty good and tune up minute slack on a drop in match trigger. The trigger overtravel adjustment is a cool feature but probably the least used feature. If you are dropping $429 on this billet receiver set then you are probably springing for a high end trigger like the SD-3G Geissele used in this build which generally negates the use of an over travel adjustment.

SanTan is not just about offering an ambi-everything billet lower receiver with looks that deserve a supermodel to be draped over it - your choice of mental image male or female. SanTan put a ton of research into developing a design which offers all the features and cool factor with a design significantly stronger than mil-Spec forged receivers.

Their 6.9 oz billet upper receiver follows the same strategy with a design which is significantly lighter than even flat sided (non-forward assist) receivers but significantly stronger. In fact San Tan notes their upper as being the lightest on the market. Like the pocketed truss inlets on the lower, the upper is deeply trussed to reduce weight while delivering an overall stiffer upper receiver and it has the benefit of looking really cool. 

The upper receiver on the AR15 has to manage almost all the structural stress, the weight of the barrel and high tension exerted on the now fashionable barrel length handguards. San Tan's feelings were that the standard Mil-Spec upper receivers do not deliver the strength required to support the stresses of long modern handguards. Through 3D CAD modeling, San Tan Tactical removed material from unstressed areas and bulked up others, the result was an upper with an unparalleled strength to weight ratio which is both stronger and lighter than Mil-Spec receivers.

I have always liked the SanTan Tactical SST-15 designs and built a few builds based on the receivers. Sometime handguard compatibility can be challenging with some custom billet receivers, however the San Tan set has broad fit compatibility with many handguards and I have never had an issue.

Functionally the San Tan set offers many features beyond the standard AR15 receiver in addition to the weight reduction and significantly upgraded fit and finish. Sure, functionally this $429 upper and lower receiver set runs adn guns about the same as a mil-spec receiver set, however with the flared mag well, lighter overall weight, and some improved ergonomics, it becomes an enhanced experience but with better handling… you know like a Bugatti.

Upper Features:
* Model – STT PILLAR Lite Upper
* Caliber - Multi-Cal
* Weight – 6.9 Ounces / 195 Grams
* Material - Billet 7075-T651 Aerospace Grade Aluminum
* Finish - Matte Black MIL-A-8625 Type III Hard Anodize
* Component Compatibility - Works With All Mil-Spec AR-15\M16 Components Including ALL Known Handguard Options Currently Available.

Lower Features:
* Huge 1.38" Integrally Machined Magazine Well Flare
* San Tan Tactical Truss Pockets for Increased Structural Rigidity
* Bullet Pictogram Safety Selector Markings
* Set Screw Trigger Creep Adjustment
* Set Screw Upper Take Down Tension Adjustment
* Shooter Ready Finger Rest
* Oversized Winter Trigger Guard Perfect for Gloved Hands
* Dowel Screw Assembly
* Ultra-Grip Texture on All Controls
* Backed by STT’s Unmatched Lifetime Warranty
* Made in the USA

SanTan Tactical - http://www.santantactical.com

Other Manufacturers Featured
Burris - http://www.burrisoptics.com/
Geissele - http://geissele.com/

No comments: