Archive for the 'Firearms' Category

AR-15 Architecture: The Key To Function

BY Herschel Smith
5 days, 10 hours ago

Shooting Sports USA.

Armalite’s original blueprints specified a 20-inch barrel, 12-inch (measured from the upper-receiver face) gas-port location and a ballpark 12,500 PSI gas-port pressure level. Those are the “rifle” specifications, which work just fine. Therefore, the problem isn’t in the design. Rather, it’s in the redesign. The shorter the front end is, the more redesign has its influence. Carbine-length barrels and especially pistol-length barrels create a condition where using the same ammo there is higher gas pressure at the gas port.

An AR-15 has a “direct impingement” system. Propellant gas is bled off through a gas port in the barrel, this gas goes through the gas manifold or “gas block,” through a gas tube, and into the carrier key atop the bolt carrier, and that’s the end of the line—the resultant force deposited into the key starts the bolt-carrier assembly in motion.

Think of this gas system as a pressure chamber with two valves—one at the gas port and the other at the muzzle, and the moving bullet opens each valve as it crosses each plane. Therefore, the spacing of the valves matters greatly.

The better way to think of this is each is an orifice (even though an adjustable gas block is an adjustable orifice), not a valve.

As the bullet enters the barrel bore and moves forward, the space (volume) behind the bullet is increasing, which lowers the pressure of the contained gas behind it. More available barrel-bore volume before the gas port translates to lower pressure at the port. So, post-gas-port barrel length influences how long the system is “sealed” under full pressure, and the shorter the length, the shorter time. Again, the bullet is serving as a plug that’s sealing all the pressure in the system—until it exits.

[ … ]

Approximate figures for M855 (genuine 5.56 NATO) chamber pressure is about 60,000 PSI; pistol-location gas port pressure, 50,000; carbine-location, 33,000; mid-length, 27,000; rifle-location, 19,000. Thus, 5.56 NATO is hot and getting hotter, and it has been for years.

Installing a heavier buffer and also a stouter buffer spring buys time. Both increase resistance to the bolt unlocking, thus delaying it from moving. The heavier buffer better resists movement and moves slower. The stouter spring increases in-battery load against the bolt carrier, increasing its resistance to initial movement, and the carrier also then moves slower coming back against the buffer.

“Just put an adjustable gas block on it” is also routine advice, and, yes, that helps, but ideally such devices should be used to tune function. If it’s needed just to make the gun run, then the chances are certain something else was missed, most likely in the architecture. That’s where we’ll find the cure.

[ … ]

That’s easy enough with a carbine-length front, 16-inch barrel. A mid-length gas port is located 2 inches farther ahead of carbine-standard. It effectively also shortens the post-port distance by the same amount meaning lower pressure getting in and a shorter time the system is under maximum pressure. Both are good things.

If you’ve got a hankering for an AR-platform pistol, choosing a 10.5- or 11.5-inch barrel makes it possible to get a carbine-length gas system affixed, and that is a 3-inch additional length over the common 4-inch pistol-port, and a significant reduction in post-port length. That really tames a little gun.

I think it’s becoming fairly routine advice to choose the right gas system for your gun as a first step to correct over- or under-gassed systems, rather than tinkering with the gas block.

This is what the author is calling the “architectural” solution to the problem.  This isn’t exactly the same thing as having an adjustable gas block on a new AR-10 6.5 Creedmoor with a fixed 20″ barrel for folks who want to shoot hotter loads or those who want to hand load specialized cartridges and need to make slight adjustments on the block to ensure reliable operation.

When Jeff Quinn Puts On Gloves, It’s Serious Shooting

BY Herschel Smith
1 week ago

Jerry Miculek: Hidden Revolver Safety

BY Herschel Smith
1 week, 3 days ago

For Those Of You Who Have AR500 Plates

BY Herschel Smith
1 week, 4 days ago

I just can’t see .243 as an effective deer rifle because of its high velocity (penetration without deposition of energy), but I guess some guys swear by it.

What Does “MilSpec” Really Mean Anyway?

BY Herschel Smith
1 week, 6 days ago

Shooting Illustrated.

Let’s start with a simple definition: Mil-spec is “A document that describes the essential technical requirements for military-unique materiel or substantially modified commercial items. MIL-STD-961 covers the content and format for defense specifications.” In simple terms, mil-spec is a list of standards to which goods sold to the U.S. military must adhere. These standards might apply to truck tires, hats, t-shirts, and yes, firearms and ammunition. There is even a spec that specifies “Requirements for swim fins made of gum rubber for wear by military personnel for swimming purposes and for general utility.” Exciting stuff.

In the munitions context, a standardized “spec” ensures that everyone is armed with firearms that are of equal quality and with interchangeable parts. This simplifies logistics and ensures a basic level of quality. In the marketing world, mil-spec has taken on a life of its own. It is promoted as some sort of gold standard for quality when, in fact, it is a floor rather than a ceiling. The military itself is rarely at the cutting edge of innovation, instead relying on private industry to meet the needs of the force. Just because a product meets the mil-spec doesn’t mean that is the best thing on the block.

[ … ]

If a firearm truly meets the military specification, we know that it satisfies a baseline standard for quality. If you’ve ever slept in a military sleeping bag, used a military backpack or hiked in military boots, you’ll probably agree that the issued items are rarely the best on the market. The same goes for firearms, which is something that we should all take into account when making our buying decisions. Just because a product is right for the military, doesn’t mean that it is the right choice for you.

Sounds like something I said before.  “Don’t slip past these paragraphs, because they explain why “Milspec” is 1:7.  It isn’t because 1:7 shoots M193 or M855 more accurately.  It’s because of the weight of tracer rounds.  As we’ve discussed before, the term Milspec doesn’t mean better, or worse, or anything at all except that it precisely meets the specifications outlined in the purchase order(s), excepting whatever variance notifications they might make on a given batch of guns.”

Cool 45-70 Lever Gun From Mad Pig Customs

BY Herschel Smith
2 weeks ago

I expected the price to be astronomical, and while it ain’t cheap, it’s lower than I expected.  The MadPigCustoms web site can be found here.

Paul Harrell Reviews The Ruger 57

BY Herschel Smith
2 weeks, 1 day ago

Army Next-Generation “Technology”

BY Herschel Smith
3 weeks ago

LAS VEGAS — An Israeli company, working with Sig Sauer, recently showed a version of its high-tech, smart-shooter technology that the U.S. Army is currently evaluating in its Next Generation Squad Weapon Fire Control competition.

Smart Shooter Ltd. demonstrated its SMASH Fire Control System at a Sig-hosted range day for SHOT Show 2020. The SMASH is designed to help improve the accuracy of any shooter engaging stationary or moving targets in both day and night conditions, said Devin Schweiss of Smart Shooter Inc.

The SMASH “allows you to acquire, lock on and engage targets” using a weapon-mounted optic and special pistol grip that “allows the weapon to fire only when it’s a guaranteed hit,” he said.

“We are currently competing in the Next Generation Squad Weapon Fire Control competition … with a similar technology,” Schweiss told “We are still adapting it, but it’s going to be a pretty good solution.”

Last summer, Army weapons officials invited defense firms to design and build prototypes of an advanced fire control system to go with service’s Next-Generation Squad Weapon (NGSW), a 6.8mm system that includes rifle and automatic rifle variants to replace the M4A1 and M249 squad automatic weapon in infantry and other close-combat units.

Smart Shooter has teamed with Sig, which was selected by the Army, along with teams from General Dynamics Ordnance and Tactical Systems Inc. and Textron Systems, for the final phase of the NGSW effort. If all goes well, the service plans to begin equipping infantry brigade combat teams with both NGSW variants and fire-control systems in the first quarter of 2023.

The SMASH features a lock button that’s mounted on the weapon’s handguard. The shooter looks through the SMASH optic, places the crosshairs on the target and presses the button to mark the target with a tiny rectangle.

As the information is fed back into the computer, the shooter keeps the crosshairs on the target and pulls the trigger, but the weapon will not fire unless the sights are lined up properly. If the target moves suddenly, the shooter continues to keep the crosshairs on the target. When the shot is lined up, the SMASH will fire the weapon, Schweiss said.

As opposed to, you know, like, um, maybe, perhaps, teaching shooters to shoot.

I’m sure this will work out swimmingly.

Any Monkey Could Clean A Gun

BY Herschel Smith
3 weeks ago

WiscoDave sends this video.  If a monkey can do it, then there’s no reason to stress test an AR-15 to see how many rounds we can put through it without cleaning before we destroy it.

Diagnosing And Fixing Eye Dominance Issues

BY Herschel Smith
3 weeks, 1 day ago

I’m left eye dominant but shoot with my right eye.  It’s what I’ve always done, I’ve done it an awful lot, and my brain knows what I want to do now.

My Marine son described for me how the Marine Corps deals with eye dominance issues.  The USMC doesn’t abide lack of conformity and uniformity.

He fixed eye dominance issues with his “boots” by putting a patch over their left eye for several weeks and giving them menial chores around the barracks.  Soon enough, the brain reprograms itself.  My eye doctor also described for me various experiments the Army did a number of decades ago with glasses designed to make the wearer see upside down and letting them live that way for a period of time.

The brain can be reprogrammed.

26th MEU (10)
Abu Muqawama (12)
ACOG (2)
ACOGs (1)
Afghan National Army (36)
Afghan National Police (17)
Afghanistan (679)
Afghanistan SOFA (4)
Agriculture in COIN (3)
AGW (1)
Air Force (35)
Air Power (9)
al Qaeda (83)
Ali al-Sistani (1)
America (19)
Ammunition (96)
Animals (58)
Ansar al Sunna (15)
Anthropology (3)
Antonin Scalia (1)
AR-15s (215)
Arghandab River Valley (1)
Arlington Cemetery (2)
Army (74)
Assassinations (2)
Assault Weapon Ban (27)
Australian Army (6)
Azerbaijan (4)
Backpacking (2)
Badr Organization (8)
Baitullah Mehsud (21)
Basra (17)
BATFE (87)
Battle of Bari Alai (2)
Battle of Wanat (18)
Battle Space Weight (3)
Bin Laden (7)
Blogroll (2)
Blogs (16)
Body Armor (18)
Books (3)
Border War (11)
Brady Campaign (1)
Britain (38)
British Army (35)
Camping (4)
Canada (2)
Castle Doctrine (1)
Caucasus (6)
Center For a New American Security (8)
Charity (3)
China (10)
Christmas (11)
CIA (28)
Civilian National Security Force (3)
Col. Gian Gentile (9)
Combat Outposts (3)
Combat Video (2)
Concerned Citizens (6)
Constabulary Actions (3)
Coolness Factor (2)
COP Keating (4)
Corruption in COIN (4)
Council on Foreign Relations (1)
Counterinsurgency (216)
DADT (2)
David Rohde (1)
Defense Contractors (2)
Department of Defense (151)
Department of Homeland Security (24)
Disaster Preparedness (4)
Distributed Operations (5)
Dogs (12)
Donald Trump (25)
Drone Campaign (3)
EFV (3)
Egypt (12)
El Salvador (1)
Embassy Security (1)
Enemy Spotters (1)
Expeditionary Warfare (17)
F-22 (2)
F-35 (1)
Fallujah (17)
Far East (3)
Fathers and Sons (2)
Favorite (1)
Fazlullah (3)
FBI (31)
Featured (180)
Federal Firearms Laws (18)
Financing the Taliban (2)
Firearms (1,090)
Football (1)
Force Projection (35)
Force Protection (4)
Force Transformation (1)
Foreign Policy (27)
Fukushima Reactor Accident (6)
Ganjgal (1)
Garmsir (1)
general (15)
General Amos (1)
General James Mattis (1)
General McChrystal (43)
General McKiernan (6)
General Rodriguez (3)
General Suleimani (9)
Georgia (19)
Google (1)
Gulbuddin Hekmatyar (1)
Gun Control (1,205)
Guns (1,592)
Guns In National Parks (3)
Haditha Roundup (10)
Haiti (2)
Haqqani Network (9)
Hate Mail (8)
Hekmatyar (1)
Heroism (4)
Hezbollah (12)
High Capacity Magazines (14)
High Value Targets (9)
Homecoming (1)
Homeland Security (1)
Horses (1)
Humor (24)
ICOS (1)
IEDs (7)
Immigration (88)
India (10)
Infantry (4)
Information Warfare (2)
Infrastructure (2)
Intelligence (23)
Intelligence Bulletin (6)
Iran (170)
Iraq (379)
Iraq SOFA (23)
Islamic Facism (62)
Islamists (92)
Israel (18)
Jaish al Mahdi (21)
Jalalabad (1)
Japan (2)
Jihadists (80)
John Nagl (5)
Joint Intelligence Centers (1)
JRTN (1)
Kabul (1)
Kajaki Dam (1)
Kamdesh (9)
Kandahar (12)
Karachi (7)
Kashmir (2)
Khost Province (1)
Khyber (11)
Knife Blogging (4)
Korea (4)
Korengal Valley (3)
Kunar Province (20)
Kurdistan (3)
Language in COIN (5)
Language in Statecraft (1)
Language Interpreters (2)
Lashkar-e-Taiba (2)
Law Enforcement (3)
Lawfare (7)
Leadership (6)
Lebanon (6)
Leon Panetta (2)
Let Them Fight (2)
Libya (14)
Lines of Effort (3)
Littoral Combat (8)
Logistics (50)
Long Guns (1)
Lt. Col. Allen West (2)
Marine Corps (259)
Marines in Bakwa (1)
Marines in Helmand (67)
Marjah (4)
Media (43)
Memorial Day (5)
Mexican Cartels (35)
Mexico (49)
Michael Yon (5)
Micromanaging the Military (7)
Middle East (1)
Military Blogging (26)
Military Contractors (4)
Military Equipment (24)
Militia (5)
Mitt Romney (3)
Monetary Policy (1)
Moqtada al Sadr (2)
Mosul (4)
Mountains (25)
MRAPs (1)
Mullah Baradar (1)
Mullah Fazlullah (1)
Mullah Omar (3)
Musa Qala (4)
Music (21)
Muslim Brotherhood (6)
Nation Building (2)
National Internet IDs (1)
National Rifle Association (69)
NATO (15)
Navy (22)
Navy Corpsman (1)
NCOs (3)
News (1)
NGOs (2)
Nicholas Schmidle (2)
Now Zad (19)
NSA (3)
NSA James L. Jones (6)
Nuclear (57)
Nuristan (8)
Obama Administration (221)
Offshore Balancing (1)
Operation Alljah (7)
Operation Khanjar (14)
Ossetia (7)
Pakistan (165)
Paktya Province (1)
Palestine (5)
Patriotism (7)
Patrolling (1)
Pech River Valley (11)
Personal (60)
Petraeus (14)
Pictures (1)
Piracy (13)
Pistol (2)
Pizzagate (21)
Police (452)
Police in COIN (3)
Policy (15)
Politics (504)
Poppy (2)
PPEs (1)
Prisons in Counterinsurgency (12)
Project Gunrunner (20)
PRTs (1)
Qatar (1)
Quadrennial Defense Review (2)
Quds Force (13)
Quetta Shura (1)
RAND (3)
Recommended Reading (14)
Refueling Tanker (1)
Religion (173)
Religion and Insurgency (19)
Reuters (1)
Rick Perry (4)
Rifles (1)
Roads (4)
Rolling Stone (1)
Ron Paul (1)
ROTC (1)
Rules of Engagement (75)
Rumsfeld (1)
Russia (30)
Sabbatical (1)
Sangin (1)
Saqlawiyah (1)
Satellite Patrols (2)
Saudi Arabia (4)
Scenes from Iraq (1)
Second Amendment (311)
Second Amendment Quick Hits (2)
Secretary Gates (9)
Sharia Law (3)
Shura Ittehad-ul-Mujahiden (1)
SIIC (2)
Sirajuddin Haqqani (1)
Small Wars (72)
Snipers (9)
Sniveling Lackeys (2)
Soft Power (4)
Somalia (8)
Sons of Afghanistan (1)
Sons of Iraq (2)
Special Forces (28)
Squad Rushes (1)
State Department (21)
Statistics (1)
Sunni Insurgency (10)
Support to Infantry Ratio (1)
Supreme Court (6)
Survival (29)
SWAT Raids (55)
Syria (38)
Tactical Drills (2)
Tactical Gear (4)
Taliban (167)
Taliban Massing of Forces (4)
Tarmiyah (1)
TBI (1)
Technology (17)
Tehrik-i-Taliban (78)
Terrain in Combat (1)
Terrorism (95)
Thanksgiving (9)
The Anbar Narrative (23)
The Art of War (5)
The Fallen (1)
The Long War (20)
The Surge (3)
The Wounded (13)
Thomas Barnett (1)
Transnational Insurgencies (5)
Tribes (5)
TSA (20)
TSA Ineptitude (12)
TTPs (3)
U.S. Border Patrol (5)
U.S. Border Security (14)
U.S. Sovereignty (17)
UAVs (2)
UBL (4)
Ukraine (3)
Uncategorized (56)
Universal Background Check (3)
Unrestricted Warfare (4)
USS Iwo Jima (2)
USS San Antonio (1)
Uzbekistan (1)
V-22 Osprey (4)
Veterans (3)
Vietnam (1)
War & Warfare (221)
War & Warfare (40)
War Movies (4)
War Reporting (19)
Wardak Province (1)
Warriors (6)
Waziristan (1)
Weapons and Tactics (64)
West Point (1)
Winter Operations (1)
Women in Combat (21)
WTF? (1)
Yemen (1)

February 2020
January 2020
December 2019
November 2019
October 2019
September 2019
August 2019
July 2019
June 2019
May 2019
April 2019
March 2019
February 2019
January 2019
December 2018
November 2018
October 2018
September 2018
August 2018
July 2018
June 2018
May 2018
April 2018
March 2018
February 2018
January 2018
December 2017
November 2017
October 2017
September 2017
August 2017
July 2017
June 2017
May 2017
April 2017
March 2017
February 2017
January 2017
December 2016
November 2016
October 2016
September 2016
August 2016
July 2016
June 2016
May 2016
April 2016
March 2016
February 2016
January 2016
December 2015
November 2015
October 2015
September 2015
August 2015
July 2015
June 2015
May 2015
April 2015
March 2015
February 2015
January 2015
December 2014
November 2014
October 2014
September 2014
August 2014
July 2014
June 2014
May 2014
April 2014
March 2014
February 2014
January 2014
December 2013
November 2013
October 2013
September 2013
August 2013
July 2013
June 2013
May 2013
April 2013
March 2013
February 2013
January 2013
December 2012
November 2012
October 2012
September 2012
August 2012
July 2012
June 2012
May 2012
April 2012
March 2012
February 2012
January 2012
December 2011
November 2011
October 2011
September 2011
August 2011
July 2011
June 2011
May 2011
April 2011
March 2011
February 2011
January 2011
December 2010
November 2010
October 2010
September 2010
August 2010
July 2010
June 2010
May 2010
April 2010
March 2010
February 2010
January 2010
December 2009
November 2009
October 2009
September 2009
August 2009
July 2009
June 2009
May 2009
April 2009
March 2009
February 2009
January 2009
December 2008
November 2008
October 2008
September 2008
August 2008
July 2008
June 2008
May 2008
April 2008
March 2008
February 2008
January 2008
December 2007
November 2007
October 2007
September 2007
August 2007
July 2007
June 2007
May 2007
April 2007
March 2007
February 2007
January 2007
December 2006
November 2006
October 2006
September 2006
August 2006
July 2006
June 2006
May 2006

about · archives · contact · register

Copyright © 2006-2020 Captain's Journal. All rights reserved.