December 23rd, 2019

ShotBlock — In-Chamber Safety Plug Device NEW!

chamber flag plug orange Shot block safety device barrel brush

Here’s a new safety device that should prove useful for firearms, particularly pistols. The patented ShotBlock is a hi-viz orange foam chamber plug mated to an orange brush extension that goes in the barrel. This serves the same purpose as a Chamber Flag or Empty Chamber Indicator (ECI), but is more compact (and multi-purpose). With the Shot Block in place a round cannot be chambered. That should, with most firearms, render the gun safe, and unable to fire.*

Currently, the bright orange ShotBlock safety plugs are available for .380 ACP, 9mm Luger, .40 SW, and .223 Remington. Soon versions will be offered for .45 ACP and .308 Winchester as well. Watch the Video to see how this works:

The ShotBlock works by blocking the ability to chamber a round. The ShotBlock is attached to an “extended protection indicator” (i.e. an orange nylon brush). The plug and brush are placed into the barrel with the wide end of the plug on the breech lip. The extended protection indicator (orange brush) can be trimmed to fit the barrel length. Having the tip of brush visible at the end of the gun barrel confirms the Shot Block is in the chamber. As an added benefit, you can spray an anti-corrosion product on the brush for long-term storage.

chamber flag plug orange Shot block safety device barrel brush

The inventors state: “Once the ShotBlock is in the barrel of the gun you can easily manipulate the weapon safely, and any attempt to load the firearm will cause the bullet to be wedged inside the Shot Block, and prevent the [cartridge] from going inside the breach.”

Shot Block is Patented
The inventor of the ShotBlock, Bill Masters, has been awarded two U.S. Patents for this product: Nos. 9,448,024 and 9,310,149, both for “Firearm Safety and Chamber Block Indicator”. Bill explains why he invented the ShotBlock: “I had the idea for the ShotBlock after visiting a shooting range with my wife. The owner brought it out of the case and held it facing my wife without clearing it. He finally handed it to me and I cleared it. I left there telling myself there should be an easy way to let the customer know it was safe … to prevent someone quickly loading the weapon and doing bad things with it.”

Bill Masters is an engineer, inventor, designer, entrepreneur, and business advisor. He holds the first 3D printing patent, along with patents for other 3D printing technologies and CAD. He founded Perception Kayaks, which revolutionized the industry through by using molded plastics instead of fiberglass.

For more information on the ShotBlock visit: www.TheShotBlock.com.

Alternative Product Available Soon from Chamber-View
Chamber-View will soon offer a chamber plug for pistols. Like the ShotBlock, Chamber-View’s Universal Empty Chamber Indicator (ECI) prevents a round from chambering. Unlike the ShotBlock, there is no barrel brush, but a large bright orange extension wing serves as an Empty Chamber Indicator:

chamber flag plug orange Shot block eci safety device barrel brush


* We are concerned however, that with some type of floating firing pins in semi-auto systems, it still might be possible to get a primer strike. This might happen if a round is stripped from the magazine and the firing pin moves forward from inertia as the pistol slide or bolt carrier moves forward rapidly and then stops. It’s unlikely a light strike could cause a round to fire, but check your firearm with dummy rounds before assuming it is 100% safe.