The U.S. Supreme Court has granted Second Amendment Foundation (SAF) petitions for a writ of certiorari, in legal actions challenging state/local laws restricting “assault weapons”. In two notable cases — Viramontes v. Cook County and Grant v. Higgins — the Supreme Court has determined to consider SAF’s challenges to the bans on so-called “assault weapons” in Illinois and Connecticut.
Originally filed in 2021, Viramontes challenges the Cook County (Illinois) ban on many popular, commonly-owned modern guns, which was the precursor for the nearly identical statewide ban passed by the Illinois legislature.
In Grant v. Higgins, SAF challenges Connecticut’s broad ban on common, mag-fed, semi-automatic rifles — both by name and by feature set. After a troubling and misguided preliminary injunction decision from the Second Circuit Court of Appeals, SAF presented the case to the Supreme Court for consideration.
“The Supreme Court’s decision to hear these pivotal cases will finally provide the courts the necessary guidance as it relates to the types of arms protected by the Second Amendment,” said SAF Executive Director Adam Kraut. “The modern semi-automatic rifles banned in Cook County, Connecticut and elsewhere are among the most commonly owned firearms in the country, placing them well within the scope of the Second Amendment. The Second Amendment protects arms in common use for lawful purposes, and it’s hard to argue that a type of rifle that potentially outnumbers Ford F-150 trucks in America doesn’t meet that standard.”
SAF is joined in Viramontes v. Cook County by the Firearms Policy Coalition and two private citizens, and is joined in Grant v. Higgins by the Connecticut Citizens Defense League and three private citizens.
The SAF correctly argues that AR-15 type rifles are protected by the Second Amendment and are commonly used for home defense.
AccurateShooter’s Editor trains with .22 LR Anschutz model 64R back in 2008.
Rimfire Tactical Matches Aren’t Really New
NRL22 and PRS 22 rimfire shooting disciplines are fun, affordable forms of competition. We’re pleased to see the rapid growth of NRL22 and PRS rimfire. However, the concept of a rimfire tactical/practical match is not new — at least on the West Coast. Way before anyone every heard of PRS, California shooting clubs conducted “Rimfire Tactical” matches. These matches were first fired nearly two decades ago. CLICK HERE to read our comprehensive Rimfire Tactical report from way back in 2008. That article includes free targets, ballistics charts, and a complete run-down on suitable rimfire rifles.
The Concept Behind the Rimfire Tactical Match by Bill Erwin
Many guys who shoot long-range tactical matches practice with .22 LR rifles of similar configuration. Rimfire ammo is way more affordable than centerfire, you do not need a big range facility, and shooting rimfire saves wear and tear on your centerfire rifle. Further, for learning how to read the wind, there really is no better training tool than a 22 LR, even as close as 50 yards. Check out this table showing how a .22 LR ballistics compare to .308 Win:
.22 LR vs. .308, Distances for Equal 10 MPH Wind Drift
This table shows the corresponding distances at which a 10 mph full-value crosswind pushes a .22 LR bullet and .308 projectile the same amount. Values are based on 0.130 BC for a 40gr .22 LR bullet, and 0.496 BC for 175gr .308 bullet.
22 LR 40gr 1050 fps
50 yd Wind 1.0″
75 yd Wind 2.2″
100 yd Wind 3.8″
125 yd Wind 5.8″
150 yd Wind 8.2″
175 yd Wind 11.0″
200 yd Wind 14.3″
.308 Win 175gr 2650 fps
130 yd Wind 1.07″
180 yd Wind 2.15″
230 yd Wind 3.68″
280 yd Wind 5.63″
330 yd Wind 7.98″
380 yd Wind 10.71″
440 yd Wind 14.56″
This table shows how the .22 LR can be an effective substitute for a .308 Win during training. Because the smaller bullet drifts more in the wind, a .22 LR rimfire shooter will experience roughly the same crosswind effects as if he was shooting a 175gr .308 Win twice as far out. So, rimfire work can teach you to dope the wind like a .308 Win, but at less than half the distance. Shooting a .22 LR at 100 yards is like shooting a .308 Win (with 175gr SMK) at 230 yards.
SPECIAL BONUS–Rimfire Tactical Precision Targets
These FREE targets by DesertFrog are offered in Adobe Acrobat format for easy printing. CLICK HERE to download all six targets as a .ZIP archive.
Rimfire Training Target for Fun Matches
Here’s a rimfire training target with “big to small” target circles. Start with the largest circles, then move to the smaller ones in sequence. This systematic drill provides increasing challenge shot-by-shot. Novices often are quite surprised to see their accuracy improve as they move from bigger to smaller aiming points. That provides positive feedback — always a good thing.
Right Click and “Save as” to download printable PDF versions of target.
Getting started in long-range shooting? Need some pointers on gun set-up and hardware options? Bryan Litz of Applied Ballistics has created a helpful series of videos for the NSSF covering long range shooting. Bryan, a past F-TR Long-Range National Champion and Chief Ballistician for Berger Bullets, knows his stuff. His Applied Ballistics squad was the winning team at the 2016 King of 2 Miles event. Here are four (4) videos, each covering a topic of interest for long-range shooters. Running 3-4 minutes each, these videos can help you get started, and invest wisely when acquiring your next long-range rifle, scope, and accessories.
Long Range Precision — The Keys to Success
TIP for Plotting Long Range Trajectories: You want to know the true, actual ballistic coefficients of your loads. The BCs listed by manufacturers for their projectiles may be somewhat unreliable — the real BC could be higher or lower (and BC can change with velocity). That can result in problems at longer distances. Using sophisticated equipment, Applied Ballistics has measured true BCs for hundreds of projectiles. Plugging these verified numbers into your Ballistics App can improve your hit percentage at long range.
Tools of Choice — Purpose-Built Long Range Rifles
TIP for Choosing a Rifle: When you’re selecting a rifle for long range shooting, it’s important to understand your application and objectives. The applications for long-range shooting can be very refined. You have to select all the details of your application to select the correct rifle. Here are two examples — a semi-auto AR-platform rifle with scope and a bolt-action Fullbore (Palma) rifle with aperture sights. There are many other long range disciplines — F-TR for example. The F-TR rig uses a bipod and rear bag and a scope. To be competitive, a modern F-TR rig should shoot well under half-MOA.
Equipment Advice — Upgrading Your Hardware
TIP for Upgrading Your Rifle: At some point factory rifle owners will recognize weak links in the equipment chain. You can run that factory rifle for quite some time, but the barrel is eventually what’s going to hold you back. The twist-rate may not be high enough to stabilize the high-BC bullets. So the first thing you’re going to want to upgrade is the barrel. You want to get a fast twist-rate barrel with a chamber that is optimized for the bullet you’ll be shooting. A good-quality, custom barrel will be easier to clean, and it will improve the overall accuracy and precision of your shooting.
Big Boomers — Large-Caliber Rifles for Long Range
TIP for Shooting Hard-Recoiling Rifles: Bryan Litz defines “Large Caliber” as .338 caliber and bigger. These rifles can shoot heavy bullets with high BCs. However there are some trade-offs. It can be hard to maintain good fundamentals of marksmanship (trigger control, sight alignment) when you’re fighting heavy recoil and burning 100+ grains of powder. You’re dealing with the challenges that high energy brings. You want a muzzle brake with any cartridge .338 or above. Also, when considering lathe-turned solid bullets, remember that these typically have less sectional density compared to lead-cored bullets with similar profiles. This affects ballistics as well as recoil energy.
For affordable, low-recoil shooting fun it’s hard to beat a semi-auto .22 LR. While Ruger’s 10/22 is the most popular semi-auto .22 LR rifle, many manufacturers are now offering AR-style self-loading rimfire rifles. We like AR-style .22 LR rigs for Rimfire Tactical Matches and 3-Gun cross-training. With an AR-style rimfire rifle you can train with low-cost ammunition while enjoying the same ergonomics, controls, and sighting systems found on your centerfire ARs.
If you shoot service rifle, and want to train at a fraction of the cost of shooting centerfire, a rimfire AR clone makes sense. This allows you to practice with a rifle with the same feel, balance, and ergonomics of your .223 Rem/5.56×45 service rifle.
These rimfire versions of the AR-15 are excellent training tools for 3-Gun and tactical match shooters. You can practice with less expensive rimfire ammo, and save wear and tear on your centerfire ARs. Rimfire AR clones also work great for Rimfire Tactical Matches.
Below we feature a variety of popular .22 LR rimfire AR-style rifles, including the Smith & Wesson M&P 15-22, the Tippman Arms series of rimfire ARs, and the HK 416 marketed by Walther.
Smith & Wesson M&P 15-22
Smith & Wesson has upgraded its M&P 15-22, a fun rifle that we’ve praised in the past. The latest M&P 15-22 Sport MOE SL model (Magpul Original Equipment Slim Line) features a more comfortable handguard, an improved grip, and an adjustable Magpul buttstock. The dedicated .22 LR M&P rifle retains the look and features of the company’s popular M&P rifle line, with the enhanced ergonomics of Magpul furniture. It’s offered with Flat Dark Earth (tan) furniture or dressed in matte black.
Field Testing the Smith & Wesson M&P 15-22
Smith & Wesson’s 15-22 is a nice little rifle. The M&P 15-22 is designed and built as a true .22 LR semi-auto from the ground up, with ergonomics (and most controls) identical to a centerfire M&P 15 rifle. NRA reviewer Colon Noir tested the M&P 15-22 and was impressed: “This gun is unbelievably fun to shoot. There is virtually no recoil. The non-existent recoil makes shooting fast a breeze. Yeah, the magazine is a little quirky… but in the grand scheme of things, this gun feels like a full-out AR-15. The M&P 15-22 makes for a great training companion. I would place this gun in the ‘Fun Box’ — it’s reliable enough that you can have a fun time shooting. I’m picking one up, because it’s guns like these that make you truly realize how fun shooting is.”
Here’s a Video Review of the M&P 15-22 by the NRA’s Colin Noir
Tippmann Arms .22 LR AR-Type Rifles
Tippmann Arms makes a large variety of AR-15 style rimfire rifles. Tippmann also offers “house-brand” .22 LR magazines that work great with virtually all .22 LR ammunition — even the low-cost bulk ammo. To learn more, watch the videos below, which demonstrate the excellent functionality and reliability of the Tippmann AR clones. We also recommend the Shooting Sports USA Review of the Tippman Arms M4.
Owners have been very impressed with these Tippmann .22 LR semi-auto rifles. They are very reliable and have ergonomics/layout identical to a centerfire AR15. That makes them ideal for cross-training. Here are comments from some Tippman .22 LR rifle owners:
“Wanted a dedicated .22 LR to shoot with my 22 suppressor. I have a CMMG .22 LR conversion for use in my ARs. I just didn’t like ‘dirtying’ up my regular ARs shooting rimfire. So I bought the Tippmann. Very impressed with the gun. Runs well, and great quality. And I hear they have great customer service. And unlike some other “22LR” ARs, the Tippman is identical to a regular AR as far as controls, feel, and operation. Great for training, or plinking!”
“The wife and I have been running a Tippmann Redline in matches for a year now. Great rifle and company. Picked-up one of the speedloaders last fall and it makes a huge difference in both speed and comfort. No more sore thumb syndrome from loading those 25-round mags.”
Walther HK 416 D145RS .22 LR Rifle
Walther Arms offered an excellent, high-quality .22 LR AR-15 clone sold with the Heckler Koch (HK) label. The HK 416 D is a good cross trainer with high-quality construction and good reliability. The HK 416 D145RS Semi-Automatic Rifle in .22 L.R. is manufactured exclusively by Walther under license from HK. It is the only genuine HK tactical rimfire replica available.
Good Guide for PRS/NRL Competitors
Currently, PRS/NRL tactical competition is the fastest growing rifle shooting discipline with both centerfire and rimfire matches around the country. Are you thinking of getting started in the Practical/Tactical shooting game? Looking for ways to be more stable when shooting from unconventional positions? Then you may want to read Marcus Blanchard’s Practical Shooter’s Guide (A How-To Approach for Unconventional Firing Positions and Training).
Unlike almost every “how to shoot” book on the market, Blanchard’s work focuses on the shooting skills and positions you need to succeed in PRS and NRL matches and similar tactical competitions.
Blanchard provides clear advice on shooting from barricades, from roof-tops, from steep angles. Blanchard says you need to train for these types of challenges: “I believe the largest factor in the improvement of the average shooter isn’t necessarily the gear; it’s the way the shooter approaches obstacles and how they properly train for them.”
Blanchard also offers good tips on shooting fundamentals. Here’s an example:
Blanchard on Trigger Control
“There will always be some amount of wobble when shooting in positions other than prone, and timing the shot to go off when the reticle is within the target is difficult to accomplish when poor trigger techniques are employed. The most common [mistake] I have seen is ‘slapping’ the trigger. The finger is usually hovering off the trigger, and when the shooter determines that NOW is the time to fire, they quickly pull their finger to the rear and ‘slap’ the trigger. The finger never pulls the trigger in the same place and often provokes a sympathetic contraction of the rest of the muscles in the hand, which results in unwanted movement before the bullet exits the muzzle.”
Author Marcus Blanchard has the credentials. A Marine Corps veteran, Blanchard is a regular Top 10 finisher in Precision Rifle Series events. In 2015 Blanchard was ranked 8th overall (nationwide) in the PRS series at year’s end. In 2016 Blanchard won the New Mexico Precision Rifleman’s Championship.
Check out the Table of Contents to see the Topics Covered:
Click image above to view larger Table of Contents.
6.5 Guys Recommend Practical Shooter’s Guide
The 6.5 Guys have reviewed Blanchard’s book and they recommend it highly: “What’s a good book for the beginning shooter who wants to get into long range precision rifle or the intermediate shooter who wants to improve his scores? [The Practical Shooter’s Guide] is particularly useful because it explores firing from various positions and props that are encountered in long range precision rifle [events]. This knowledge is completely missing from more traditional books where the shooter is usually slung up and shooting at a paper target. Marcus… goes into considerable detail about shooting from rooftops, reverse rooftops, side slopes, tank traps, barricades etc. This is the type of information that is very difficult to find. We consider ourselves reasonably knowledgeable shooters and this book provided us with new and useful information.” CLICK HERE for 6.5 Guys REVIEW.
6.5 Guys Review Marcus Blanchard’s Practical Shooter’s Guide
Former USMC scout-sniper Frank Galli explains that there is no voodoo when it comes to precision rifle marksmanship, but there ARE techniques that, when practiced, make the difference between good marksmanship and great marksmanship. Understanding the reasons that a bullet hits or doesn’t hit its intended target at ultra-long distances is a crucial element to learning.
Galli’s explanations of how to understand and compensate for wind speed and direction are excellent. In this book, Galli offers great wind-reading advice.
Published in 2020, Galli’s treatise is four years newer than Blanchard’s book, so it includes more of the latest gear and equipment. Galli’s book covers the fundamentals of precision marksmanship with easy-to-understand methodology. The book follow the same instruction process Galli uses in his live marksmanship classes (CLASS REPORT HERE).
This well-illustrated, 272-page book (2020 ed.) covers the latest equipment (scopes, LRFs, chassis systems, magazines, bags, bipods, tripods) favored by tactical competitors in PRS/NRL type matches.
Are you looking to get started in tactical/practical competitions? Or perhaps you already have have some PRS/NRL experience but want to upgrade your equipment and enhance your match results. Here are eight videos that can help you improve your game. These videos feature top PRS/NRL competitors and knowledgeable manufacturers’ representatives. You’ll find other related videos on the Long Range Precision Shooters YouTube channel.
Shooting a PRS Match for the First Time
Here’s an amusing video from the land Down-Under — Australia. The video covers a club PRS match, showing various shooting positions. Around the world, the PRS discipline is growing rapidly, particularly with younger marksmen under 35. The matches are fun and fast-paced and the sport is much more dynamic and physically challenging than benchrest or F-Class competition.
Building a Custom PRS/NRL Rig
Action, trigger, barrel, chassis, rails, and optics — this video from Burris covers all the key components of the modern PRS/NRL rifle. This video discusses the pros/cons of various configurations and the explains what to look for in a PRS/NRL riflescope.
How Accurate Are the Top PRS Shooters?
In this video, MDT put three top centerfire PRS shooters to the test, running them through some of the most difficult stages. The goal? To showcase the level of accuracy and precision these top shooters can achieve. From shooting off barricades to hitting targets from rooftops and rocks, these shooters demonstrate why they are considered among the best in the world. Top-tier modern PRS/NRL rifles when shot prone from a bipod at 100 yards can do 1/3-MOA or better for three shots.
Cartridge Choice for PRS and Tactical Competition
This video reviews many of the different cartridge options popular for PRS-style competition. The video examines pros and cons of various cartridge choices, focusing on accuracy, recoil, mag-feeding, and value for money. This segment features G.A. Precision owner/founder George Gardner.
Most top PRS shooters are using 6mm cartridges these days. These deliver excellent accuracy with lower recoil and cheaper bullet cost. Popular choices include 6 Dasher, 6 BRA, 6mm Creedmoor, 6XC, and the new 6GT cartridge, which is sort of a stretched version of a 6mmBR. It has a bit more case length for better feeding, and greater case capacity than a 6BR so you can shoot 105-108 grain bullets at 2950 fps with ease. That’s a popular Dasher accuracy node that the 6GT can achieve at somewhat lower pressures.
CLICK HERE for a full write-up on a 6GT rifle build by Mike McCasland (Texas Precision). This includes load development suggestions and a 6GT reamer print. The popular 0.120″ freebore chamber allows for the majority of high-BC 6mm projectiles. Mike had good luck with the pointed 107gr Sierra Match Kings (SMK), as well as the 110gr Hornady A-Tips in his rifle.
Road to the PRS
This video from Kestrel offers good advice on getting started in PRS/NRL shooting. Experts demonstrate multiple shooting positions and offer advice on shooting from barricades. Topics covered include rate of fire, scope use, and equipment selection.
PRS Tactical Division Explained
In this video MDT Shooter Matt Stiner explains the basics of competition in the PRS Tactical division. The video covers rifle, cartridge choice, optics, and key accessories. He also explains how to set up your PRS Tactical rig for best results. In addition Matt talks about bullet and brass options.
Savage 110 Elite Precision — Good Production Class Choice
This Alabama Arsenal video shows the Savage 110 Elite Precision on PRS Match stages using bags, tripods, and bipods, firing from stone barriers, field frames, and wood platform supports. If you are in the market for a PRS rifle, this video, which now has 355,000 views, is well worth watching. It covers specific features including trigger, chassis, magazines, and Atlas attachment. NOTE: The price limit for Production Class has risen significantly over the years, with a current MSRP max of $3000 for the rifle and $2500 for the optic.
PRS on a Budget — Converting a Basic Rifle for PRS Use
Top of the line rifles for competition are exceedingly expensive, but there is another option if you have a rifle in the safe that doesn’t get much use. Top F-Class shooter and wind coach Keith Glasscock notes: “I converted my .223 Remington varmint rifle into a Tactical class/PRS training rifle to save costs on ammunition and barrels so I can get better, faster.” Keith shows a very logical way to get started in the PRS/NRL game.
Many hunters and precision rifle competitors use muzzle brakes because these ported devices reduce felt recoil significantly. That makes a real difference getting back on target for quick follow-up shots. While many rifle owners appreciate the benefits of muzzle brakes, they may also neglect their brakes, allowing hard carbon and powder residue to build up. Not good. You should regularly clean your muzzle brake to remove fouling and carbon build-up.
As Mark Edgreen posted: “Carbon build up on the crown and in the brake is a recipe for poor accuracy.” And another gunsmith reported that customers complained about guns that “shot out way too early” but they only needed to have the brakes cleaned.
Gunsmith and PRS/NRL competitor Jim See recently reminded his Facebook Fans about the importance of cleaning muzzle brakes: “How many times do I have to say it? You need to maintain your rifles. Clean your muzzle brakes people!”. Jim, who runs Elite Accuracy LLC, notes that hard carbon build-up in brakes can definitely harm accuracy. Look at this example:
Muzzle Brake Cleaning Methods
There are various methods for cleaning a brake, we list a variety of techniques, but we would start with NON-corrosive ultrasound. You’ll want to remove the muzzle device before doing these tasks.
1. Use Ultrasonic Cleaning Machine with cleaning solution. This may be the most efficient method: “I place my brake in the ultrasonic cleaner. Shiney as new.” (Jim Moseley).
2. Spray with commercial Carb Cleaner and brush. Then apply anti-corrosion coating.
3. Soak in half hydrogen peroxide and half vinegar. Suggestion: “Let sit over night and carbon melts off. Brush remaining carbon off, rinse and put the brake back on.” Apply anti-corrosive before mounting.
4. Soak in 50/50 solution of water and white vinegar and brush. (Be sure to apply anti-corrosion coating, such as Eezox, after soaking).
5. Tumble in liquid solution with stainless pins. Comment: “Comes out slightly faded, but perfectly clean on stainless, non-painted brakes though.” Warning — do NOT do this with threaded brakes — tumbling could affect threads of screw-on brakes. Also, tumbling can harm painted or Cerakote finishes.
Gunsmithing Tip: By fitting the muzzle brake so that the barrel crown is slightly forward, it is easier to wipe carbon fouling off the end of the barrel. See photo:
This shocking photo of destroyed AR-15 bits and pieces was posted on Facebook by William Walter, a firearms instructor. William said this was “The worst AR-15 blow-up I have ever seen. The case head literally atomized …you can see the brass residue on the parts. The bolt was split in two also.”
There’s nothing inherently wrong with AR-platform rifles (well, except that they run dirty). Over the past six decades Eugene Stoner’s semi-automatic design has proven its merits in military and civilian applications. You may not know, but the original AR from 1955 was a .30-caliber. The Armalite AR-10 shot the 7.62×51 cartridge. Later, at the request of the U.S. Military, Armalite created a smaller version that became the M16/AR15. The rest was history. Now there are millions of AR “black rifles” in the hands of soldiers and sportsmen.
With so many ARs in circulation, it’s no surprise that some get used by folks who don’t know how to hand-load or otherwise fail to follow safe gun practices. The AR is actually a pretty sturdy rifle, but when it’s fed bad ammo, or abused, bad things can happen. Very bad things… commonly known as Kabooms.
The American Shooting Journal (ASJ) compiled a set of particularly extreme AR Kabooms. Compiling the “evidence” from various web sites, ASJ published nine (9) of the most Unbelievable AR-15 Fails (but sadly the photos seem to be unavailable now). Here are two of the worst “AR-15 Fails”.
Nothing but busted parts after this catastrophic Kaboom…
Notice the bolt is still stuck in the barrel extension … with the rest of the gun in pieces.
Another view of this sad blow-up…
These catastrophic AR failures are eye-openers, that’s for sure. ASJ cautions: “Any weapon can fail if given the wrong ammunition, faulty reloads or a plugged barrel. Always be aware of what can happen at anytime if you fail to follow common sense and gun safety rules.”
ASJ Sources: Photobucket, Armory Blog, Pinterest, Northeastern Arms, Eric Nestor
Wouldn’t it be cool if you could adjust the bolt cycling energy on your AR-platform rifle? Turn down the cycling rate for slow fire at the bench or varmint hunting. Crank up the energy for 3-Gun matches and rapid-fire disciplines. This IS possible with a handy accessory that fits on your barrel. Wilson Combat offers an Adjustable Lo-Profile AR Gas Block for direct gas impingement AR-type rifles. Wilson Combat’s adjustable gas block replaces a standard AR gas block and allows you to tune your AR’s gas system for smoother cycling and enhanced reliability. Wilson Combat explains: “Adjusting your rifle’s gas port will lower or increase your bolt’’s cyclic rate. This tailors your rifle’s performance to your unique needs.”
A simple adjustment of the hex screw at the front of the block modulates the gas volume allowing you to tune your rifle’s function to your favorite loads. This is very handy when shooting non-standard AR calibers, unusual hand-loads, or suppressed rifles. Adjustable Gas Block systems are sold as complete kits starting at $61.07. Wilson Combat offers two diameters (.750″, .875″) so you can select the right dimensions for your rifle configuration and barrel diameter. The blocks are Chromoly steel with a black Melonited finish.
Package Includes:
Adjustable Gas Block (Melonite Finish)
Adjustment Set Screw (Installed)
Straight Gas Tube (Installed, Gas Tube Pin Installed)
Readers often ask “What’s the difference between a Weaver scope rail and a Picatinny Rail?” The answer is not as simple as it seems. The dimensions of a Picatinny Rail should be consistent (from one rail-maker to another), since there IS a government spec. Conversely, there is some variance in “Weaver-style” rails. The width of the groove is the most important difference between Picatinny Rails and Weaver-type rails. “Mil-spec” Picatinny rails will have a grove width of 0.206″ while Weaver rails typically have a narrower, 0.180″ groove width.
Does your rifle have a Weaver Rail or Picatinny Rail? Check the dimensions to be sure.
A while back, Brownells had a helpful GunTech™ Article that discussed the Picatinny Rail vs. Weaver Rail. That article explained:
What are the differences between the ‘Picatinny’ and the ‘Weaver’ systems? The profile of the two systems is virtually identical. Depending on the quality of the machining done by the manufacturer, the two systems should be indistinguishable from the profile. The key difference lies in the placement of the recoil grooves and with width of the grooves. MIL-STD-1913 (Picatinny) grooves are .206″ wide and have a center-to-center width of .394”. The placement of these grooves has to be consistent in order for it to be a true Picatinny MIL-STD system. Weaver systems have a .180” width of recoil groove and are not necessarily consistent in a center-to-center measurement from one groove to the next.
In many instances, a Weaver system has a specific application that it is machined for, so interchangeability is not necessarily an issue. A MIL-STD-1913 system must adhere to the specifications listed above in order for it to be considered MIL-STD, since the military desires uniformity in the recoil grooves to allow for different systems to be mounted on the weapon with no concern for compatibility.
Now, what does this mean? Boiled down, it means that accessories designed for a Weaver system will, in most cases, fit on a Picatinny system. The reverse, however, is probably not the case. Due to the larger recoil groove, Picatinny accessories will not fit a Weaver system. There are, of course, exceptions to every rule, but for a good rule-of-thumb, [full-width] Picatinny won’t fit Weaver, but Weaver accessories WILL fit Picatinny.
Originally filed in 2021, Viramontes challenges the Cook County (Illinois) ban on many popular, commonly-owned modern guns, which was the precursor for the nearly identical statewide ban passed by the Illinois legislature.
