BOTW: BKKSW's "Riot Buster" 300 BLK

Tom R
by Tom R

The sixteenth Installment of Build of the Week was contributed by BKKSW. I have just recently embraced the 300 BLK (after constant hounding and derision from Pete). I went with a very much “off-the-shelf” SIG MCX Rattler PSB, and now that I am part of the cult, I wonder why I waited so long… BKKSW’s 300 BLK weapon is well loaded and, based on the write up, is very well thought up (note: I named it “Riot Buster” for him; it somehow seemed fitting).

Keep the submissions coming in! We are publishing them in the order in which they were received (with the exception of a single person submitting back to back–those will get spread out).

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  • Anderson Manufacturing AM15 upper/lower forgings
  • G2 10” Keymod Hand guard
  • 10.5” .300 BLK 1:8 Twist
  • 1x Specwar/Omega Trifecta Flash Hider
  • BCM .750 gas block drilled and taper pinned
  • Spikes pistol length gas tube
  • BCM medium length charging handle
  • Palmetto NiB logo’d BCG w/BCM extractor spring,cup,o-ring kit
  • LAW Tactical Gen 3 folding stock adapter
  • KAK Shockwave buffer tube
  • Brownells buffer spring
  • DPMS H3 buffer
  • BCM QD end plate
  • Geissele SSA trigger
  • Brownells LPK
  • Battlearms Ambi-selector
  • Battlearms mag release button
  • Magpul aluminum trigger guard
  • BCM pistol grip
  • KAK Shockwave Blade Pistol Stabilizer
  • Magpul sling in one-point config
  • Magpul G2 BUIS
  • BCM Keymod Short vertical grip
  • Trijicon MRO optic
  • ADM QD mount
  • Trijicon MRO cover
  • Surefire Scout light
  • Surefire Picatinny Rail light switch

I’ll admit it, watching the riots and looting in response to the Trayvon Martin and Michael Brown shootings caused me to think long and hard about what if my wife who works in our small mid-west downtown called and something like this was happening, what if another family member was caught in the area, after doing our best to avoid such a situation what if we were there and the choice now became my concealed carry piece, or something better. Of course, I’d want better. Who wouldn’t?

In such a scenario I would want maximum legal firepower to 300m knowing most use would be under 50m. I’d want the largest heaviest caliber projectile that could still fill a 30 round mag. Heck, ideally I’d like to fill a D-60 if they ever worked reliably with the heavier bullets. Ideally, I’d want the weapon to be heavy enough to soak up recoil and the application won’t have me carrying it far so if it’s 7-8lbs I’m okay with that. I just want a controllable effective close range high capacity carbine that’s legal with my CCL and easy to get in/out of a vehicle.

I’ll admit a bit of a conundrum with my selection. The vertical grip would be a problem with a pistol, and I can’t have an SBR in my state. By the addition of the vertical grip at the current LOP of the brace setup I have by definition a “firearm.” I can’t legally carry a long gun or even a firearm loaded with my CCL, so I guess I’ll have to have the carbine and mags separate until on-site. Somehow, if this weapon comes into play these are the least of my worries, but I recognize that if I was going to carry this full time loaded as a car/truck gun it could eventually become an issue.

Economy is always a concern, but I want my weapons to be built with the same care and precision to which I build my precision rifles. The Anderson forgings are mil-spec and work fine, but I’m still going to final ream the pin holes, face the upper, and deburr both forgings to ensure all is good. The barrel is plenty accurate enough for my uses and offhand I can ring the 12” steels out to 300m with regularity. But I still want my familiar hand guard diameter and shape, mag release, pistol grip, and selector controls.

Why a Shockwave and not the Sig or other braces? Weight, texture, and snaggles. On this gun, the weight itself isn’t an issue, but I find the Sig braces to be tacky with their rubber-like surfaces and I want the weapon to be able to glide over other surfaces. They also come with a strap I’d rather not worry about snagging somewhere.. and if you carefully read the ATF letters if it comes that way you’re good. But you can’t remove a strap if it comes with one. I say that acknowledging this is a really murky area not everyone agrees on. And after 2000 rounds, I really don’t notice a comfort factor difference. And I wouldn’t care if there were one under the scenario it was built for.

The weapon must be as reliable as possible, and I’ve found once properly tuned the bigger difference is in bullet shape/weight. The LAW folding stock adapter was added because once on sight I might have to move on foot for a limited period and I wanted the entire assembly to fit in a knapsack. And it does that nicely. So far, with roughly 2000 rounds through the barrel, I’ve found zero issues with this adapter or any other component.

The Trijicon MRO IS my primary optic and as such, I won’t worry about turning it on. I change my batteries in all my devices every birthday (makes for a fun day of celebration having outlived another lithium cell..:)), and I can’t envision even the brightest setting failing me in that time frame. I’ve found the MRO as reliable as my T1/2 Micro’s, or as my Vortex Crossfire or various other red dots.. but then I realize my sample size is purely anecdotal. Still, you can’t deny the MRO is robust looking and since the several I own have been flawless in operation I’m okay with them. And if failure, the Magpul BUIS will be ready to go.

I’ve come to appreciate the economy of the Palmetto Armory Logo’d (because they list the specs for these and not all the specs for their others) NiB bolt carrier groups. But as with any bolt carrier group I disassemble and check for outsized tooling marks that might need addressing, deburr, and finally change out the extractor spring/cup/o-ring with the BCM products. Why? I find comfort using what’s worked for me over and over again. I’m not going to try and save five bucks on such an important part of the weapon.

A flash hider over a brake for a .300BLK should be obvious, but why spend the extra money for the Trifecta? I chose the Trifecta in hope that my state, or my country, eventually enacts their version of the safe hearing act. And it looks cool!

I’ll admit I actually enjoy building and Cerakoting my own weapons. After blasting and degreasing I put on the H-133T Cross Canyon Arms Green and several other oven-cure colors on the main pieces, and then after assembly goes over the final pieces and touch it all up with air-coat pieces and my airbrush. If you let the air-coat cure for 7-10 days I’ve found it nearly as durable as the oven-coat products.

Why the stencils? (my pmags are stenciled the same) I’ve been at the range where someone has picked up anothers AR thinking it was theirs. A few weren’t discovered until the sheepish faced individual had fired a few rounds. Imagine if a pmag full of 5.56mm found its way inside a .300 BLK weapon.. So, if I have a AR-15 chambered in other than its most popular cartridge, I’m going to identify it’s caliber in some way.

I’ll admit it. I have a lot of fun laying out and building my own weapons. The more I can do the better, so I Cerakote, Parkerize, and apply other finishes when appropriate. I’ve probably collected more tools and jigs than many. But it’s fun, and I get the real benefit of having the weapon I want built as well as I want to put the time into. And with each, I learn. And yes, I even enjoy answering questions..

What I don’t enjoy is living in a world where the political world affects the application of justice. I don’t like that my success in defending myself could be termed 100% justifiable in one county, but the next county over find myself charged for the same act of self-defense, because of the politics of an ambitious district attorney. If I must defend myself or the life of my loved ones or an innocent, the uncertainty of a justifiable outcome must be the furthest thought in my mind until after the incident is over. So like anything else, we prepare with a prayer we’ll never have to use our tools or skill. But if we do, my hope it to be around to see how it all turns out..

Take care.

Comment below to ask BKKSW questions about his build.

TFB’s BOTW Prize Packs are provided by STRIKE INDUSTRIES

Tom R
Tom R

Tom is a former Navy Corpsman that spent some time bumbling around the deserts of Iraq with a Marine Recon unit, kicking in tent flaps and harassing sheep. Prior to that he was a paramedic somewhere in DFW, also doing some Executive Protection work between shifts. Now that those exciting days are behind him, he teaches wilderness medicine and runs an on-demand medical staffing business. He hopes that his posts will help you find solid gear that will survive whatever you can throw at it--he is known (in certain circles) for his curse...ahem, find the breaking point of anything.You can reach him at tom.r AT or at

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