Working with Springs

Springs are probably the parts most often neglected in a firearm. Other parts that are worn out are usually obvious once we get inside a firearm, but springs don’t always show visual signs of wear’ even when they’re getting close to the point of failure. In this article, I’ll cover some of the signs to look for in order to prevent the failure of a spring when a firearm is needed most.

The purpose of a spring is to absorb energy, store it, and then release that energy to perform a desired function during a specific process. The springs most commonly seen in firearms are one of three types’t he flat, the compression (coil), and the torsion (mousetrap) spring. Flat Springs Flat-style springs were first used almost exclusively on firearms during the flintlock and percussion eras. Even today, there are some applications where a flat-style spring is still the best choice.

When parts need to interact in an area that’s especially tight and a sturdy force is required to make the parts work together, a short, stiff, flat spring would most likely be the designer’s choice. You’ll see flat springs used in most antique muzzleloader ignition systems. The lockwork will usually have two flat springs’one for the hammer and one for the trigger.

You have to admire the gunsmiths of those times, since making a flat spring requires skill in the handwork along with the knowledge of how to harden and temper a spring so it will work correctly. With today’s labor rates, some of these springs could run $50 or more if a replacement had to be made from scratch, considering the time involved. If you work with old muzzleloaders, you probably already have a copy of the Dixie Gun Works catalog.

If you anticipate working on older muzzleloaders, the $5 price of this catalog is a bargain for all the knowledge you’ll find inside. Dixie’s replacement flat springs area bargain considering the time and effort it would take you to make one. If they don’t have exactly what you need, you might find a spring they offer that can be adapted to your specific need.

Magazine followers in most boltaction rifles with integral box-style magazines use a W-shaped flat spring to force the ammunition upward so the bolt can send around into the chamber. Remarkably, I have seen some magazine-follower springs that were pulled out of Mauser 98 rifles manufactured in the early 1930s that still had enough strength to get the job done.

Nevertheless, whenever one of my customers wants to discuss the sporterizing of a military rifle, I suggest the replacement of these springs In this photo, "H" is a flat hammer spring and "T" is a flat trigger spring. as a precautionary procedure. The current Brownells catalog lists replacement magazinefollower springs that will work for almost all the military Mausers we’re likely to encounter.

And in a pinch, springs made for the Remington Model 700 and Winchester Model 70 can be easily substituted with very little alteration. Now that cowboy-action shooting is one of the hot new games in town, we’re seeing more and more singleaction-type revolvers in need of a tuneup. All of the Colt Single Action Army revolvers and most all of its clones use some type of flat spring in their lockwork.

Replacements can be obtained from Wolff Gunsprings (another good catalog to have) and there’s quite an array of single-action-revolver springs in the Brownells catalog. Compression Springs These days, most good compression or coil springs are made of piano wire (ASTM A228) and the processes used to manufacture them have evolved to the point where it’s possible to create an almost perfect product at a very reasonable cost.

Still, because of the excellent performance produced from these modern methods and materials, complacency can create a false sense of security; springs don’t last forever. Corrosion, especially where pitting is

taking place, will weaken the base metal of a spring. Pitting results in stress being distributed unevenly, making a spring weaker and more prone to failure. The compression spring is the most common type used in modern firearms. They’re used for firing-pin and action-return springs, as well as for striker springs. In a bolt-action rifle, the striker spring stores energy when the striker is held back until the trigger releases the striker to ignite the primer.

All compression-type springs will develop a "set" over time. Thus, if a firearm is stored with the hammer or striker in the cocked position for an extended period of time, the spring may not have enough strength to get the job done. What this means is that a compression spring will shorten up much more when under a prolonged, sustained, load’unless the tension is relieved using a "snap-cap" of some sort. When the "snap" of the hammer or striker turns into along drawn-out click, it’s time to change that spring.

The Government Model 1911 pistol and relatively all copies use a compression spring to work the slide during the firing sequence. Wolff makes compression springs for 1911style pistols with a bit of extra length built into the spring to account for the set that will eventually occur.

When In this case, it will be replaced with anew Wolff spring for positive ignition. the set gets shorter than the working limit of the spring’s length, you’ll notice that the pistol is not ejecting empties as well as it once did or the slide doesn’t return with quite as much oomph when chambering another round. There are quite a few different weight ratings for recoil springs for 1911-style pistols, because there are so many variations in ammunition that can be fed through one of these guns.

A recoil spring made to withstand the energy from a 230-grain hardball must be substantially stronger than the spring needed for 185grain lead target load. Therefore, the springs should be changed accordingly. All semi-auto pistol magazines will benefit from having extra-power springs installed to ensure feeding. This is especially true for pistols used in self-defense and law-enforcement applications, where magazines are stored full of ammunition for extended periods of time.

Semi-automatic centerfire hunting rifles depend on a compression spring to work the action during the firing sequence. Most of these rifles have areas along the barrel channel where rain or snow can get into the barrel channel and rust the coils of the action spring. Whenever one of these rifles appears in your shop for maintenance, a thorough inspection of this spring should beapart of your routine. Spring service packs are available that are quite handy when you need to replace a missing or worn-out spring.

When replacing a worn-out spring, it’s a simple matter to measure the wire diameter with your caliper and then measure the inside and outside diameters of the old spring to determine what will be needed from one of the service packs. If you need to shorten the length of a replacement spring, it’s important to observe how that spring is placed in the firearm. Leaving a clipped end unfinished is not a good practice if the spring needs to stand up or lay straight when it’s in position to do its job.

Some judicious grinding using a stationary belt sander to square up the clipped end is a good idea in most cases. But don’t get the spring so hot that it loses its temper. A factory-provided spring should never have coils clipped off to lighten trigger pull; this is just begging for trouble in the form of ignition failure. It makes little difference whether the spring has a rightor left-hand helix when a single spring is used alone.

In those instances where a spring will need to work inside another spring, like those that work the action bar inside the Model 100 Winchester or the recoil spring inside the Colt Officer’s Model, the outer spring should have a right-hand helix and the inner spring should have a lefthand helix (or vice-versa) so the coils don’t get tangled up with one another

and impede the action they were designed to perform. The same idea applies for a spring that needs to work over a threaded rod. The spring should be the opposite helix (turn) of the thread. Torsion Springs The torsion-style spring is seen mainly on triggers and hammers, where one leg of the spring is fixed in a stationary position, while the other leg transfers the force held in the spring coils to create movement of the hammer or trigger.

Most often, there is a pin going through the coils to hold the spring in position. The pin must not be a close fit to the inside diameter of the spring coils, because the diameter of the coils is somewhat reduced while under tension. This could cause binding on the pin’s outside diameter and restrict its intended purpose. It’s very important to install a torsion spring so that it works in the direction in which the coils of the spring are wound.

I have seen these springs installed backward after a gunowner has taken a firearm apart for cleaning. Failures of function due to this errant installation are common. Disk-Type Springs We don’t see disk-style springs used very often on firearms, with the one exception being the wave-style set of three constant-force springs used to maintain the handguard in position on AR-15-type rifles. There are several styles of disk springs. One type I use on occasion is known as the Belleville disk spring.

Occasionally you’ll encounter an older firearm where the fit between parts isn’t quite what it was when it was newer. There may be some side play with a hammer or trigger, for example. This is where one of the various types of spring-disk washers can save the day. Sliding a Belleville ( ) spring washer over a pin and up against apart that has side-to-side play will usually eliminate the side play while allowing the parts to interact freely.

Belleville washers are convex, with a slight bevel from the outside toward the inside. These spring washers are used under the head of a fastener to create a slight pressure that acts to keep the fastener from loosening due to vibration. This style of spring washer can be stacked, one on top of the other, to take up an unwanted gap. In many cases, this is simpler and more expedient than trying to make up a spacer to restore the alignment between two parts.

Conclusions To better understand the workings of any firearm, we need to know how the springs inside that firearm were intended to work. Only then can we restore proper functioning when something’s not working as it should. Springs do wear out. Moreover, they get weak from being compressed for extended periods of time. They can break due to rust and pitting. And they sometimes get rubbed thin just from doing their job.

When you find a spring that exhibits visible or mechanical signs of wear in a malfunctioning firearm, it’s probably the first part that should be replaced.