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Stolen from Kim at Splendid Isolation (A Great Blog BTW)

This post is appearing early in the morning so that if any of you are off to the range later, you can make the necessary preparations.

A while back I was reading about the practice method known as “spot shooting”, something I’ve been doing forever, but didn’t know it had acquired a name.  Put simply, it’s a routine whereby you fill a blank target sheet with small circles, then shoot one (and only one) shot per circle in the shortest possible time.  Here’s how to do it.

The next time you go to the range for some .22 practice, get one of the cheap full-sized silhouette paper targets (or, if you’re one of the people who buys the things in bulk, then takes a few to each range visit, keep one aside after your regular practice session).  Then affix a hundred small circle targets onto the paper, spaced about two inches (2″) apart — rows are best so you can see where you are — then load up the necessary numbers of mags, and get going.  Here are two examples of the target spots, the Birchwood Casey orange dot and the Shoot-N-C type:

These are the two more expensive ways to practice this drill, by the way;  real  Cheap Bastards (e.g. Kim) will go to a discount store or online and buy rolls of the little price tags such as made by ChromaLabel, which have the advantage of being multicolored, available in 1″, 3/4″, 1/2″ or even smaller sizes, and they typically cost less than a penny per spot.

The advantage of this is that it’s a really cheap method of practice, and it is cruelly unforgiving:  there’s no “9-ring” or similar types of escape routes — just a small circle which either has a bullet-hole in it, or not.  It is also unbelievably tiring, mentally.  People often boast of how they blast off many hundreds of rounds at a single practice session, but a hundred in a single practice routine?  Be my guest:  if you’ve never done it before, it’s a whole lot tougher than it looks.

At the end of the routine, you score yourself out of 100, and anything less than 100% represents failure (there is no participation trophy in precision shooting).  When / if you do manage to get 100% consistently (good luck with that), then start timing yourself (or have a range buddy time you) and try to get that same 100% in less and less time.  (It doesn’t need to be stopwatch-perfect, especially the first few times you do it.)

And by the way:  if you’ve never done this before, start with larger dots (1″), and then gradually work your way down to the smaller ones when / if you master that size (uh huh).  For my .22 rifles, I shoot 1″ spots at 25 yards unscoped, and 3/4″ spots scoped;  for a handgun, it’s 1″ or 3/4″ spots at ten yards.

Here’s what this wonderful practice routine teaches you:

  • Patience.  If you lose patience, you will start missing the target.  It’s that simple.
  • Target re-acquisition.  How to move on and aim at the next dot, make sure your aim is true, then fire and move on… one hundred times.
  • Making sure your sight picture is perfect.  No matter how well you think you know your gun, after about the tenth shot, you will know exactly — exactly — what sight picture will score a hit.  Now do it again, ninety times in a row.

About six months ago I got my first-ever 100, with a Browning Buck Mark borrowed from Daughter, shooting the 3/4″ dots at 10 yards.  I felt like doing a victory lap around the range, or at least a Happy Dance, but apparently jumping around like a lunatic while firing bullets into the ceiling is not Acceptable Range Behavior, for some reason.

By the way, this is also a great drill when practicing with your carry piece — only it gets a little expensive even if you’re reloading.  I normally end my session with just one or two mags’ worth of dots (say fifteen rounds of .45 ACP or twenty-five rounds of 9mm), also at ten yards.  I don’t take too much time either:  I shoot what I call “rapid deliberate”, which is about 1.5 seconds per shot.  And if you think this is too easy, toughen up your scoring criteria:  half a bullet circumference or more in the dot counts as a hit, less than half is a miss.  I’ve never yet hit every dot with my carry pieces, but I’ve come damn close.

All this shooting talk is making my finger itch.  If you’ll excuse me… I think I need to go load up my range bag.

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Open Bolt vs. Closed Bolt By Robert A. Sadowski

While we might hear the terms “machine gun” and “submachine gun” a lot, a more detailed discussion will often touch on the terms “open bolt” and “closed bolt.” But, what do these terms mean?

Firearms engineers choose between open and closed bolt configurations based on intended use and performance priorities. Each design offers distinct trade-offs in manufacturing cost, accuracy, and heat dissipation.
Firearms engineers choose between open and closed bolt configurations based on intended use and performance priorities. Each design offers distinct trade-offs in manufacturing cost, accuracy, and heat dissipation.

The Differences Between Open and Closed Bolts

The difference between a firearm with an open-bolt design versus a closed-bolt design is the position of the bolt prior to firing the gun. On an open-bolt gun, the gun is ready to fire when the bolt is locked open and there is no cartridge in the chamber.

When the trigger is pulled, the bolt moved forward and strips a round from the magazine. As the bolt closes, the round is fired and the cycle continues until the trigger is no longer depressed or the gun runs empty. In a closed-bolt design, is it the opposite.

The bolt is closed and a round is in the chamber prior to firing the gun. Pulling the trigger drops the hammer, the round is fired, the action is cycled, and this continues until the trigger is released or the magazine is empty.

The MP-40 exemplifies classic open bolt engineering from World War II. German forces relied on this submachine gun’s simple, reliable design throughout the conflict. Image: Sa-kuva
The MP-40 exemplifies classic open bolt engineering from World War II. German forces relied on this submachine gun’s simple, reliable design throughout the conflict. Image: Sa-kuva

Examples of a closed-bolt design firearm include the AR-15, the Springfield Armory Hellion, MIA rifles and the Kuna pistol, to name just a few. For examples of open-bolt designs, you really need to look back at submachine guns designed during World War II.

The Sten gun’s bolt assembly shows just how simple open bolt designs really are. British engineers stripped away everything unnecessary to create an incredibly cheap and effective submachine gun. Image: International Military Antiques Inc.
The Sten gun’s bolt assembly shows just how simple open bolt designs really are. British engineers stripped away everything unnecessary to create an incredibly cheap and effective submachine gun. Image: International Military Antiques Inc.

Some of the most common and icon submachine guns during the war were an open-bolt design. The American M3 Grease GunBritish Sten SMG, and the German MP-40 Schmeisser were all open-bolt designs. Also developed during the war was the American M1941 Johnson light machine gun and the German FG 42. These two example are unique because they incorporate an open bolt in full auto and a closed bolt in semi-auto fire.

Open Bolt Design Firing Cycle

Here’s the layman’s explanation of the cycle of operation on an open-bolt design and a closed-bolt design.

Armed with an open bolt M3A1 Grease Gun, PFC Jose Ledoux-Garcia guards his M60A3 tank in West Germany during REFORGER ’85. Image: NARA
Armed with an open bolt M3A1 Grease Gun, PFC Jose Ledoux-Garcia guards his M60A3 tank in West Germany during REFORGER ’85. Image: NARA

To fire an open bolt design, whether a semi-automatic or a full-auto firearm, the first step is to  insert a magazine and then retract the bolt. In an open-bolt design, the bolt remains rearward. It is literally open and the firearm is ready to fire. Press the trigger and the sear releases the bolt, driving the bolt forward, pushing a cartridge out of the magazine and into the chamber and firing the cartridge in one swift motion. The bolt then cycles back ejecting the spent case and then moves forward to start the process over.

In a closed-bolt design, the process is different. Insert a loaded magazine and pull back on the charging handle and release it. The bolt flies forward, strips a cartridge from the magazine and runs a cartridge into the chamber. The bolt is literally closed and ready to fire. Press the trigger and either a hammer is tripped or striker released, which fires the cartridge.

Pros and Cons

In an open-bolt system, as the trigger is pressed to fire the gun the weight and mass of the bolt moves forward, jolting the gun as it slams closed. That movement can interfere with the shooter’s aim.

In a submachine, that’s not much of an issue. In a closed-bolt design, the bolt is forward and a press of the trigger releases the hammer or striker, so there is no movement in the bolt prior to firing the shot. A closed bolt design is more conducive to better accuracy.

Swedish military personnel conducting an amphibious landing operation while carrying Carl Gustaf m/45 submachine guns with water splashing around them as they move from boats to shore. Open bolt firearms function in wet conditions. Closed bolt guns require careful protection. Carl Gustaf m/45 used open bolt design. Swedish submachine guns emphasized reliability. Open bolt systems resist water damage. Amphibious operations demand robust weapons. Military firearms handle extreme environments. Open bolt mechanisms maintain operational readiness.
Swedish military personnel conducting an amphibious landing operation while carrying Carl Gustaf m/45 submachine guns. Also known as the Swedish K, the m/45 was an open bolt design. Image: Swedish Army Museum/CC BY 4.0

The advantage of an open-bolt design is realized in full-auto guns. High rates of fire create extreme heat in the chamber and barrel, which can create a dangerous situation called a “cook off.” This is where a cartridge in a heated chamber fires without the trigger being pulled. In an open-bolt design, since the bolt is open and there is no cartridge in the chamber, air cools the chamber and will prevent the risk of a cook-off.

The British Sten gun embodied open bolt design at its most basic and economical. At roughly $10 to produce, it proved you didn’t need expensive manufacturing to create an effective weapon. Image: Will Dabbs, MD
The British Sten gun embodied open bolt design at its most basic and economical. At roughly $10 to produce, it proved you didn’t need expensive manufacturing to create an effective weapon. Image: Will Dabbs, MD

Another advantage of an open-bolt design is that it generally uses fewer parts than a closed bolt design. In an open-bolt design, the firing pin is generally machined as part of the bolt. Because of the inertia caused by the bolt closing when the trigger is pressed, the fixed firing pin strikes the cartridge primer without the need for a hammer and firing pin.

A Finnish soldier crouched in a bomb crater firing a German MP-40 submachine gun during the Continuation War. Image: Sa-kuva
A Finnish soldier crouched in a bomb crater firing a German MP-40 submachine gun during the Continuation War. Image: Sa-kuva

Since open-bolt guns are inexpensive to make and use fewer parts, they were mass produced during WWII.

The American M3 Grease Gun for example cost about $20 to produced compared to other submachine guns that cost upwards of $70 at the time. The British Sten gun cost only about $10 to make during the war. Both of these open-bolt design weapons were inexpensive and quick to produce.

Sergeant Bruce E. Strickler wading through the Cu De River while carrying an M3A1 Grease Gun during a patrol mission into Elephant Valley searching for Viet Cong positions during 1967. Image: U.S.M.C.
Sergeant Bruce E. Strickler wading through the Cu De River while carrying an M3A1 Grease Gun during a patrol mission into Elephant Valley searching for Viet Cong positions during 1967. Image: U.S.M.C.

Conversely, closed-bolt designs are more complex and expensive, but can fire more accurate shots and are generally more “refined” designs. Examples of full-auto closed bolt designs would be rifles like the M16 and the M14.

Conclusion

So there you go. If you’re reading up on a machine gun design and they reference “open bolt versus closed bolt,” you’ll now understand what it means. Now that you understand the firing sequence, it’s and an open and closed case from there.