Category Archives: Arms

Tactical Rifle: Ruger SR-556

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The last time I wrote about the AR-15 rifle platform my biggest design complaint was the Direct Gas Impingement (DGI) action.  This has been a feature since the very first generation of the weapon adopted by the military over 45 years ago.  DGI contributes to the platform’s simplicity and lightness, but also has some undesirable consequences: Every time the gun fires it blasts hot propellant gasses back into the bolt carrier, baking a layer of carbon onto everything in the receiver.  Decades of military service have proven that well-made AR-15’s can withstand this abuse and continue to function reliably with just basic cleaning and lubrication.  But for obsessive owners who like to keep their guns in more immaculate condition this dirty design can be quite irritating.

When I bought my first AR-15 following the 2004 expiration of the federal “Assault Weapons” Ban I openly wondered why no manufacturer had produced a piston-driven variant of the gun, especially given the huge market for America’s favorite tactical rifle.  Since then I tracked the gradual emergence of AR-15 piston actions, first as retrofit kits, then as new uppers and complete guns.  There was a great deal of concern about the long-term reliability of converted actions, mostly because the AR-15 bolt carrier wasn’t designed to be hammered with a piston, and its geometry seemed prone to an adverse effect called “bolt carrier tilt.”  Some manufacturers, most notably LWRC, built a new action from scratch to mitigate these concerns.  However LWRC’s piston uppers were always very hard to acquire, and even today they command huge premiums.

In mid 2009 Ruger entered the AR-15 market for the first time, and they did so with a proprietary piston action.  The SR-556 now represents the best value in piston-driven AR-15s.  I sold my old DGI AR-15 to somebody less fastidious than me and last month managed to pick up a new SR-556 for just under $1500.

The SR-556 comes standard with a number of desirable upgrades over basic AR-15s.  Among them:

  • Full-length quad-rail handguards, so you can easily add as many accessories as you can carry.
  • Top-quality folding iron sights (by Troy Industries).
  • A comfortable pistol grip (by Hogue).
  • Chrome-plated bolt carrier assembly, so what little dirt does get into the action can easily be wiped off.

The piston system was executed superbly.  Only the three pieces in the front two inches need to be removed for cleaning.  The piston regulator has four positions.  In the off position the action doesn’t cycle, essentially giving you a bolt-action gun.  The first position (smallest gas opening) is suited to use with silencers, which sustain more backpressure on the action.  The second position cycles the action reliably under normal conditions, and the largest opening can be used to compensate for weak ammunition, a very dirty gun, or other harsh conditions.

Shooting the gun for the first time was a pleasure.  There were absolutely no malfuctions.  Even after sustained firing the bolt was cool to the touch (though the barrel and gas vent area still got quite hot!).  Long-term reliability on a new design may not be certain, but the fact that Ruger is comfortable enough to roll these out in quantity is reassuring.  This should certainly outlast piston systems that use DGI bolt carriers with their separate gas key: The SR-556 carrier is machined from a single piece of steel with just a little hump over the main tube to take the impact of the piston.

Out of the box this is a very good gun, but it does have a few shortcomings:

  • Like all piston guns this is both front-heavy and heavier (just under 8 pounds) than comparable DGI AR-15s (typically closer to 7 pounds).  Of course even professional users of the DGI M4s have found it beneficial to put a vertical grip on the front of their guns.  I added a GripPod ($80 from Botach) and found this mitigates the imbalance nicely, in addition to deploying a handy bipod when desired.
  • The flash suppressor has uniform slots around its entire diameter.  When shooting prone or on a table this causes some of the muzzle blast to kick up dust.  Although closed-bottom flash suppressors require indexing to install, this should be a trivial factor to accommodate on a production line.  So shame on Ruger for not equipping this with a closed-bottom flash suppressor!
  • The telescoping buttstock is a standard M4 style, which leaves a lot of play between the stock and the buffer tube.  They should have just equipped it from the start with a Magpul CTR (shown in the photo above), for which I had to pay another $80. (To fit this gun be sure to get the mil-spec, not commercial size CTR!)
  • It doesn’t come with a front sling loop or swivel.

M25 and M62 .30 caliber Tracer Bullets

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As a new handloader I thought it would be fun to add tracers to my inventory. Tracer bullets that have been pulled from surplus military ammunition can be picked up for $15/100 at gun shows or online.

I bought one bag each of M25 and M62 tracers, but since I couldn’t find any detailed information about them online I decided to analyze them myself. Ten of each are shown here, M62’s on the left. Both tracer types are marked with an orange tip. (The black residue on the bottom of the bullets is the remnant of sealant used on military ammo and comes off after a spin in a vibratory cleaner.)
MilSurpTracerBullets
MilSurpTracerBulletBases

M62 tracers are designed for .308 (7.62x51mm NATO) rifles. Overall length is 1.33″, and they have a single .05″ cannelure which leaves a bearing length of roughly .60″.

BulletSectionsM25 tracers were supposedly designed for .30-06 rifles. They are nearly identical to the M62’s except for a second cannelure that allows them to be crimped more deeply in a case. This photo shows whole and sectioned samples of M62, M25, and (for comparison) 168gr BTHP bullets.

TracerCompoundUnderBaseCupI weighed the M62’s at about 143 grains and the M25’s at about 145 grains. On both bullets the base of the copper jacket is crimped around a 1 grain copper cup about .20″ in diameter. The cup is seated almost .1″ deep from the base of the bullet on M62’s, and slightly more shallow on the M25’s — .06-.08″ from the base, which could account for the extra weight on the M25’s given that the overall length on both is the same. Ahead of the cup, and behind the lead core, is .40″ of tracer compound with a dimple in the center, shown here.

The tracer compound is brittle and powdery, and weighs only about 10 grains. It burns with a bright red flame for about 4.5 seconds and (in static tests at least) leaves behind 3-4 grains of ash.

In order to help conceal a shooter’s location these tracers are designed to not fully light up for the first 100 yards of flight. At muzzle velocities over 3000fps that’s just a tenth of a second from firing to the appearance of the full flame. I did a number of tests to try to determine the tracer compound’s ignition temperature as well as the mechanism by which this delay is achieved, but was unable to get consistent results.

First I took a tiny amount of tracer powder and put it directly on a thin nichrome wire linked to a dimmer switch and a thermocouple. I slowly raised the temperature to 900F but nothing happened. I shut down and then rapidly hit the heater with full current and got an immediate ignition. In later tests I opened the back of a tracer and put the compound in direct contact with a thick copper wire heated to 800F and still got no ignition!

In an attempt to more accurately simulate the conditions of being pushed from behind by the hot gases in a firearm I took an intact bullet and anchored its base directly to the top of a copper wire, which I slowly heated with a propane torch. It reached 540F and after some time at that temperature the entire tracer pellet ignited and ejected out of the back of the bullet, pushing the bullet 5 feet into the air and leaving the copper cup still on the test stand. That’s not what’s supposed to happen either, but it does suggest a potential failure mode: If the tracer compound ignites from anything other than its base a shooter will see a red flash and then nothing as the compound leaves the bullet and burns much faster dispersed in the air. This also confirms (as did later tests) that the tracer compound provides negligible thrust — in this extreme case accelerating the bullet less than 10fps.

[Update: Though they don’t significantly propel the bullet, burning tracers do extend the bullet’s range. In a summary of BRL research on .50 caliber bullets Robert McCoy notes, “The tracer adds heat and mass flux into the wake, which raises the base pressure and lowers the base drag. For the APIT, M20 projectile, the tracer reduces the total zero-yaw drag coefficient by approximately 7 percent, at all speeds tested.”]

Fortunately, it’s not hard to get a proper ignition of these tracers: Hitting them briefly with a propane flame will reliably ignite them, as shown in this video. Here is a photo of three burned tracers along with two of the recovered base cups.

Primer Pocket Cleaners: Lee vs RCBS

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Cleaning primer pockets of fired cases is part of the ritual of preparing accurate, reliable reloads.

RCBS sells a $15 Primer Pocket Brush Combo (Part #9574) for this purpose, consisting of a threaded handle and two threaded stainless steel wire brushes for each primer pocket size.  It is the first tool in the following photo:

The second tool shown is Lee’s $2 Primer Pocket Cleaner (Part #90101).  It is just a small blued steel cylinder with a squared-off blade on one side for small primer pockets and on the other side for large ones.

The following picture shows eight large-primer cases.  The left two have not been cleaned, showing the importance of this step of brass preparation.  The top three were cleaned with two twists of the RCBS tool, and the bottom three with two twists of the Lee tool.  I thought the RCBS would be more comfortable and easy to use, but after prepping a batch of brass I became much more concerned about what it was doing to my primer pockets:  As you can see the steel brushes leave noticeable gouges in the brass.  In contrast, the Lee tool keeps the pocket face square and relatively unscathed.

I can’t see any good coming of marring primer pockets to this degree.  Especially over repeated uses the RCBS brush is removing measurable amounts of brass, and if you didn’t need it the first time it will almost certainly be needed on subsequent cleanings since the primer pocket floor is no longer flat enough for a tool like Lee’s to make full contact.  Therefore I recommend against the RCBS tool. Lee’s much cheaper tool is a perfectly functional solution to primer pocket cleaning.

Recoil Reduction Products

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I own two over-under field shotguns.  These are light guns optimized for carrying on long walks hunting birds.  But a lighter gun means heavier recoil.  I like to take my field guns trap shooting, but it can be painful to shoot more than a few rounds with 12-gauge or even 20-gauge loads.

Competitive shooters with customized guns and release triggers laugh at the idea of using field guns for sporting clays.  “If you want less recoil you have to add more weight to the gun,” they insist.  Adding weight is certainly one way to dampen recoil.  But I’m a practical guy and I don’t want to turn my light field guns into heavy competition guns.

Fortunately there are other ways to control recoil:

  1. Fit.  This is the primary factor affecting the shooting experience of a bird gun.  If the gun doesn’t fit the shooter then the shooter won’t be able to maintain a correct shooting posture: Cheek “welded” to the stock, butt snugly in the shoulder pocket, and dominant eye aligned with the front sight bead.  If you can’t lock the gun against your cheek and shoulder then the recoil of every shot will slap you (often leaving visible bruises).  If your eye isn’t aligned with the sight then you will probably miss the target.  (The shooter’s eye serves as the rear sight on a bird gun.  It doesn’t take much sight movement to change the point of impact at 20-40 yards!)
  2. Action.  A semiautomatic action will absorb a significant amount of recoil.  Of course that doesn’t help if you’re talking about making a bolt or break action easier to shoot.
  3. Dampers.  You can dissipate recoil energy using damping mechanisms.  Almost every gun comes with a rudimentary damper in the form of a rubber recoil butt pad.  Here I review some more advanced dampers.

Edwards Recoil Reducer

Edwards Recoil Reducers are light cylinders containing a spring-buffered counterweight that absorbs and even redirects (depending on installation angle) recoil.  I got one delivered from Brownells for $60.  It looks and feels like a rugged device.  Edwards has been making these for over forty years and backs each reducer with a lifetime warranty.

Installation in a wooden stock can be a bit of a project.  Take the recoil pad off of any shotgun and you’ll discover a lot of empty space in the stock.  Before you can properly install the reducer you probably need to fill that space with some combination of dowels or other wood trimmed for a tight fit.  Then with a 7/8″ forstner bit you can carefully drill out a hole as high and parallel to the gun’s barrel as possible.  Push the recoil reducer into the hole, make sure it’s snug, and screw the recoil pad back on to hold it in place.

Installation in a hollow plastic stock is simply a matter of unscrewing the recoil pad, positioning the reducer, and filling the remaining space with sprayfoam, as shown here.

After installing the Edwards Recoil Reducer in one of my guns I took it right back to the trap field — still sore from shooting four rounds two days earlier.  The recoil reduction was immediately obvious.  I’m still working on a recoil gauge to quantify peak forces, but to me it felt like close to half of the recoil was gone.  Even after four more rounds with the gun I would have been comfortable continuing to shoot.

Graco GraCoil

Graco’s GraCoil is a butt plate that contains an adjustable piston that compresses up to 5/16″ to absorb recoil.  Compression damping is also what a good recoil pad is supposed to do, but pads aren’t adjustable and they can’t get too mushy before they impact handling.  The GraCoil spring can be tightened just enough that it doesn’t move under the pressure of your shooting stance, but then immediately starts to compress to absorb the recoil of a shot.

GraCoil plates also include a mechanism to enable significant adjustment to the position of the butt pad.  This allows for significant improvements in the fit of a shotgun (which, as noted above, is an essential feature!).  I opted to buy the GraCoil Model GC15-LP which also includes a length-of-pull adjustment.

The GraCoil needs to be ground to fit a particular stock, something I didn’t feel like attempting.  Total cost of the GC15LP with factory installation is $375.  MPC Sports will sell and install the same unit for $325.  I went with the latter vendor.  I carefully reviewed the proposed work with their gunsmith over Email and then mailed my stock to their shop in Atlanta.  The completed piece was back in my hands just a week after they received it.

After tweaking the tension on the piston and getting the butt pad in just the right place shooting with the GraCoil is so easy and natural I really could break clays all day long.

FrontSight Nevada Firearms Training

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Outside of the military, I have taken commercial firearms training courses at both the SIGARMS Academy in New Hampshire (now called the SIG SAUER Academy) and at FrontSight in Nevada.

My experience at SIG consisted of a 3-day Concealed Carry Pistol course.  They have a great indoor range where they shoot only lead-free frangible ammo, which means you can get up close with the reactive metal targets.

At FrontSight you generally have to contend with outdoor courses where you are exposed to all of the rigors of weather in the Nevada desert.  In return you get access to some very long ranges and simulators.  My first experience at FrontSight began with a promotional half-day submachine gun course.  Subsequently I have done one-day assault rifle and shotgun courses, as well as a two-day practical rifle course.  In every case I drove up each day from Las Vegas.  My best experience was with the one-day courses, which you can custom schedule almost anytime one of the longer courses isn’t in session: My wife and I had an instructor and a range to ourselves, and all ammunition was provided.  List prices for Front Sight can seem very high, but the institute’s director, Ignatius Piazza, is constantly running promotions so I would be surprised if anyone pays full tuition.  You can usually find discounted course “certificates” that cover tuition on Ebay.

The single most important variable in your experience at either institute will be your instructor.  On the whole I have been quite satisfied, though not every instructor is equally engaging or capable of adapting the content and pace of instruction to the students.  Both institutions keep a decent instructor/student ratio, so incompetent students tend not to bog things down.  One other thing you have to deal with at Front Sight is Ignatius Piazza’s cult of personality: Classroom time will include details of his personal philosophies as well as extended pitches for you to buy Front Sight membership and more courses.

CMC AR-15 Super Match Trigger Group

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A typical AR-15 does not have a good trigger: My Bushmaster’s factory trigger is heavy and not particularly crisp.  I finally broke down and bought a single-stage Chip McCormick trigger group for $176.  The advantage of this over other match triggers designed for AR-15’s is that it’s a single rugged unit, easy to install, with a 3.5-pound pull that breaks like glass.  Drawback compared to its competitors is that it is not in any way adjustable.

Freebore Boost Effects

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When I first took my .223 suppressor (Gemtech M4-02) to the range with a chronograph I was surprised, on reviewing the data, to find that it was doubling the standard deviation of muzzle velocity. Baffle suppressors are known to increase muzzle velocity in an effect known as “freebore boost.” Basically they extend the barrel length, which gives the propellant extra time to accelerate the bullet. So I was expecting to see higher velocities, but not higher variance: When I added the can to the end of the barrel average velocity went up about 50fps, but the standard deviation of velocity also went from about 22fps to 45fps!

When it comes to marksmanship anything that increases variance reduces accuracy. Are suppressors inherently bad for accuracy? After some correspondence on the SilencerTalk.com forum I decided to run a controlled experiment. I went back to the range with a stopwatch and a Mastercool infrared thermometer.

Muzzle Velocity versus Suppressor Temperature

What I found is that muzzle velocity is strongly correlated (R2 = .60) with suppressor temperature. I.e., once your can is hot your bullets will go faster. Several people hypothesized that this is simply because hot air is less dense, so it offers less resistance to the accelerating bullet. Another hypothesis is that the propellant burns more completely or more rapidly in the superheated air it encounters in the baffles, which increases the rate at which it can propel the bullet.

How hot does a suppressor get? For this experiment I shot Federal XM193 5.56mm (55gr Boat-tail ball) ammunition. On average each shot heated the 16 ounce suppressor by 10 degrees F. During one phase of the experiment I shot 30 rounds in under 90 seconds, which raised the suppressor temperature from 110 to 410 degrees F. During that extended string of shots my standard deviation was only 19fps — which is about the same variance I see when shooting without a suppressor. It took ten minutes for the suppressor to cool back down below 150F. (Ambient conditions were 62F, 25% humidity. Surface temperature in the sun was 88F. Winds were 10-15mph.)

If I may summarize liberally from the results of the experiment: A baffle suppressor essentially has two states, which we could call “Hot” and “Cold.” A suppressor is Hot when either (1) shots are fired in quick succession or (2) its temperature is above about 150F. In the first case I imagine that the baffles are still full of hot propellant vapor; in the second case the can is radiating enough heat to keep ambient air at this elevated temperature. A suppressor goes Cold as soon as ambient air seeps back in.

Using this equipment (16″ bbl and 6″ suppressor) the muzzle velocity out of a Hot suppressor is around 50fps higher than out of a Cold one. And if we look at the standard deviation of muzzle velocity when shooting Cold it comes out the same as when shooting Hot.

AR-15 with Trijicon ACOG and Gemtech M4-02 Suppressor

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A free people ought not only to be armed and disciplined, but they should have sufficient arms and ammunition to maintain a status of independence from any who might attempt to abuse them, which would include their own government.  — George Washington

Bushmaster XM15-E2S with Trijicon ACOG TA01 and Gemtech M4-02 PiranhaIf the Founding Fathers, believing that every citizen should be armed to defend his life and liberty, were handing out guns today, every man would get an AR-15.  This is the American arm you can count on to protect your family, property, and fellow man.

The Rifle

There are a number of reputable manufacturers out there building AR-15 rifles to military specifications (the AR-15 is essentially a semi-auto-only version of the M16 infantry rifle), and there are many variations.  Since this is a tactical rifle I believe it should have a collapsible stock and the shortest legal barrel (unregistered), which is 16″: This makes it as easy as possible to store, carry, and use in close quarters if necessary.  If you start with those specifications then the biggest decision you have to make on the rifle is between a handle or flat-top upper.  I like my sights up high and I qualified on the M16-A2 while on active duty, so I went with the former.  There is more flexibility for modifications if you go with the latter.

The rifle itself will set you back about $900.  I bought one of the first available post-sunset (i.e., collapsible stock + flash suppressor + 30-round magazine) Bushmaster XM15’s for a total of $870 in 2004.  Since the standard grip is too small for my hands, I spent $20 to replace it.

Sights

The standard M16A2 sight system is very effective:  Using these sights at a long-range FrontSight course I was able to reliably hit man-sized targets at 400 yards from a kneeling position.

But the rifle is capable of more accuracy than you can achieve with iron sights, which is why this gun is not fully fleshed out until you have topped it with a 4x ACOG (Advanced Combat Optical Gunsight).  The Trijicon ACOG TA01 4x32mm scope is a standard military issue accessory.  And it is a beautiful piece of hardware: It produces a bright, clear image with good eye relief.  The reticle includes a bullet-drop compensator and is tritium-illuminated so that you can use it in dark conditions.  It mounts directly in the carry handle of an AR-15 using just one screw (and even leaves a hole through which you can still use the iron sights).  It is rugged, waterproof, and warrantied for life.  It is a perfect match for the .223 assault rifle.  But it is not cheap: I waited and managed to get one for $580 on Gunbroker.com, but unless you’re lucky you’ll probably have to pay at least $700 to pick one up new.

Suppressor

There are many options for suppressing this gun.  A lot of them are “quick-detach” cans, which can be installed with a single hand and a single twist onto a special flash hider, but these options generally cost at least $300 more than screw-on silencers.  Since it’s more hazardous to shoot a gun without a suppressor, I can’t think of a reason I would want to quickly remove mine, so I went with a screw-on can.  Since Gemtech has a good reputation and reasonable prices, I chose their $500 M4-02 “Piranha” model baffle suppressor.  It makes the rifle quiet enough to shoot without ear protection.  Though since the rifle shoots around 3000fps, it is by no means quiet: The sonic crack of the bullet makes roughly as much noise as a .22 being fired out of an unsuppressed gun.  But since that sound comes from the bullet’s shockwaves reflecting off of surfaces downrange it is much more subdued than if the shot were going off right by your ear.

Shooting an unsuppressed rifle — even one like the AR-15 with a reputation for very controlled recoil — is a violent experience.  In addition to the jarring recoil there’s a deafening report coupled with the palpable shock of propellant exploding from the muzzle.  Even with a good flash hider it can be disorienting.  Now putting this silencer on the end of the barrel absorbs practically all of the muzzle blast and a lot of the remaining recoil, making shooting almost … peaceful.  One drawback, other than the weight (a full pound for this particular can, protruding an extra 6″ beyond the end of the barrel), is the heat: After just ten successive shots the suppressor becomes too hot to hold with bare hands.  Keep shooting and it starts to radiate a heat mirage that can actually interfere with the sight picture if you’re trying to make a precise group.  (But it’s just doing its job: Here’s a good picture of a red-hot suppressor after hundreds of rounds of sustained, full-auto rifle fire.)

Ammunition

Guns rated for NATO 5.56mm also shoot .223 caliber ammunition.  (These have the same dimensions, but different pressure specifications.)  Since this is a standard military round it is both cheap and plentiful.  Right now you can find it in case lots for as little as $.20/round.  Most mil-spec ammo is 55gr FMJ, which leaves the muzzle of my 16″ barrel right about 3000fps.  I have also chronographed Georgia Arms’ 68gr match-grade BTHP at just over 2600fps.  Unfortunately, with all the ammunition I have tried I have never managed to shoot better than 3 MOA with this gun (that’s 1.5″ groups at 50 yards), though I don’t know if that’s typical.

Drawbacks

You have to keep it clean.Field-stripped AR-15 The best critique of the AR-15 is a Mad Ogre classic (overboard, but they are fair complaints).  The biggest criticism can be summarized as, “The rifle defecates where it eats.”  This was due to a design trade-off (direct gas cycling) made to keep the rifle lighter and simpler.1 It results in a lot more carbon fouling in the action than you would get with a piston design.  But you don’t really have to spend 4 hours a day cleaning the gun to keep it from jamming.  (Unless you’re dragging it through mud and sand … in which case you’re probably a G.I. with four hours a day to spend cleaning it.)  In my experience if you field strip it and scrub it down with Breakfree CLP after every shooting trip it will continue to function reliably.

You will probably come across criticism of the 5.56mm cartridge.  A lot of people say you have no business putting anything smaller than 7.62mm in an assault rifle.  Again, this is a trade-off: 210 rounds of 5.56mm weigh the same as 70 rounds of 7.62mm; 7.62mm assault rifles have to be bigger and heavier to handle the larger rounds.  My reasoning: If you need to kill in one shot, and weight isn’t an issue, then use a sniper rifle.  To say that a gun doesn’t shoot the biggest round in existence is an observation, not a criticism.  (Moreover, for purposes of suppression the lower the bullet diameter the better.)

Features:

  • Light, standard weapon.  Everyone knows how to use it, fix it, and enhance it.
  • Light, cheap, plentiful ammunition.
  • Relatively easy to shoot accurately (for a large-capacity semi-auto rifle).
  • Military-spec, proven and durable design.

Drawbacks:

  • Soils itself.
  • Doesn’t operate well when not maintained.

In spite of these drawbacks, there’s a reason that this has been the standard U.S. infantry long arm for over forty years.  Every country that can afford to equip its soldiers with AR-15 variants does.  As far as I know this is still the best militia weapon you can buy: Any alternative will be heavier, less reliable, and/or more complicated.  If you need a light rifle for tactical operations — which includes the ability to easily carry and shoot a lot of rounds — then take an AR-15.

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Concealment Pistol: Smith and Wesson 642 with Crimson Trace grips

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Smith and Wesson 642My wife struggles to just rack the slide on most semi-auto pistols. Since she can hardly operate them, it’s hopeless to train her to recover from the standard malfunctions. I wanted to find a foolproof, easy-to-use, easy-to-carry gun that she would feel confident to train with and carry for self-defense. I believe that gun is the five-shot, .38-special +P Smith & Wesson 642 revolver with Crimson Trace laser-sight grips. S&W sells the gun as a package with the CT grips (model #163811), which my dealer brought in new for $455.

Double-action revolvers are foolproof. Pull the trigger and, if the cylinder can rotate onto a live round, it will fire. As a pure concealment gun the 642 shoots double-action only and has no exposed hammer to snag on anything.

This gun is light — under one pound empty. You really can’t go any lighter and still get enjoyment out of shooting .38sp +P ammunition. (S&W sells 13oz. “Airweight” revolvers that can shoot .357 magnum, but I have never heard anyone say shooting those was a pleasant experience.) So I think the 642 hits a sweet spot balancing weight and size (for ease of carry/concealment) with the ability to fire a proven defensive round.

I wouldn’t get this gun without the laser sights, which are bright enough to use in sunlight.S&W 642 with laser on target To aim conventional (barrel-mounted) sights you are supposed to focus on the front sight post, which means you’re not focusing on the threat … which is not a good idea when you have to make a split-second decision to use lethal force. Furthermore, as with any small, concealable gun, the sight radius is so small that conventional sights would have very limited accuracy anyway. The laser lets you focus on the target and point-shoot accurately. It probably also adds an intimidation factor on top of the deterrant value of the gun itself.

It is important to note that the laser sight is offset 1.2″ down and .5″ laterally from the bore.Smith and Wesson 642 bore and laser sight If this offset is maintained when the pistol is boresighted (i.e., so the laser shoots parallel to the bore) then the sights will be accurate for any distance, but will always shoot a little high and left (though certainly within the range of accuracy of a gun with a 1 7/8″ barrel). If the sight is zeroed for a specific distance then the laser will intersect the bore line and the pistol will not be accurate for any other distance.

Drawbacks

When I was first considering this class of gun, I was somewhat concerned about ammunition capacity. Unless you really practice for it, you’re not going to be able to reload a revolver in an emergency. After training with high-capacity semi-autos, where people talk about whether it’s reasonable to carry just one spare magazine (only 35 rounds?!), it’s disconcerting to think of a defensive weapon where after five shots all you have left to throw at assailants is the gun itself.

But when it comes down to it, five rounds are reasonably sufficient for both a civilian looking for a convenient carry pistol, and for a gun-fighter’s backup gun. Neither individual is relying on this gun to win a gun battle. The argument for concealed carry is that 99% of the time just brandishing a pistol will send bad guys in the other direction. If you actually have to start shooting, and both you and your assailants are locked in the fight after you’ve sent five bullets in their direction, then something is seriously wrong and it probably doesn’t matter how many extra shots you might have had after that point.

My only complaint about this particular gun is the trigger: It has a very long, heavy, non-linear (sort of two-stage) pull and reset. It takes a lot of practice and attention to control it to get good groups and to avoid yanking the barrel off target. Fortunately, the laser sight makes it easy — even fun — to dry practice the trigger pull: Just hold it on a point across the room (with a reliable backstop, please!) and try to keep the laser as steady as possible.