Do springs take a ‘set’ ?

We at D-J tailor to all kinds of clients and many are very technically minded. Like us, most of them are highly successful and have spent their life staying away from the ‘woke’ mentality as well as nanny state agenda. They reject the ‘stakeholder’ concept. They scoff at the “Diversity, Inclusion, and Equity ” (DIE) nonsense. And they don’t get anywhere near getting taken in by the man-made climate change scam. They (and us) as such have lived rich, fulfilling lives by disregarding rules proposed by despots, been remarkably non-compliant with rules proposed by miscreant bureaucracies (and gotten away with it), and done the ‘dangerous’ stuff kids did in the 30’s-70’s unencumbered by lawyers and Karens. They smoke cigars and grill big juicy steaks for dinner.

Not surprisingly, most of these clients are pro-gun libertarians. Unabashedly so.

Just like the ‘downwind turn” in aviation, the subject of springs continues to come up. Namely if one keeps a magazine full (or hammer spring/striker spring compressed in a cocked and locked gun), does the spring weaken ? For advice on this we turned to staff consultant J. J. “Slasher” Isherwood who is an avid shooter and functions as a sort of company armorer for us:

“Problem is that there’s a grain of truth to the ‘springs take a set’ myth. According to renown Romanian Metallurgical Engineer Peter Saktiv, springs DO take a bit of a ‘set.’ But it’s not what most people think. With any well constructed spring, there’s both elastic deformation as well as cyclical fatigue. If the spring is well constructed for the task at hand, the initial elastic deformation is minor (and allowed for in the specification); usually occurring within the first few cycles at maximum compression. Anyone who owns an Sig P365 can attest to this. The mags are almost impossible to load to capacity when new; after a few cycles or being kept loaded for awhile they become more manageable (although they remain some of the stiffer springed magazines I’ve ever seen).

However, after this initial ‘set,’ spring life is almost completely determined by cyclical loadings. In other words what makes them wear out and not have good tension anymore is a whole bunch of CYCLES on the spring. It’s NOT leaving them compressed. Nor are springs designed for purpose particularly fragile.

Fr’ example, if a car travels 100,000 miles and averages 45 mph during this time it’s had its engine run for around 2200 hours. Assuming an average of 2300 RPM (and that an exhaust or intake valve would function every other turn), that means a valve spring has undergone over 153 MILLION cycles during this time. In some pretty harsh conditions. And many engines go over twice as long before dying or having valve springs replaced.

Some individuals download mags to prevent a ‘set.’ All I can say to them is “don’t do that.” How many people in a gunfight ever said to themselves “Gee, I wish I had less ammo ?!?” If you’re REALLY worried about your mags, get quality mags in the first place (with quality springs) and keep them loaded to capacity. The key is to get quality mags from reputable manufacturers in the first place. I keep my Glock, Sig, and PMAGs loaded to capacity on all my ready guns. If you’re the kinda guy (or gal) who just can’t leave things alone, replace your mag springs after several years. But unless you shoot ALOT and cycle the mags ALOT, it’s really unnecessary.

Now, when it comes to recoil springs, some of them DO take a beating in cyclical loading. Especially in light guns in heavier calibers. Some not; depends wholly on the gun design and manufacturer. I recommend they comply with manufacturer guidance when it comes to recoil springs or if they’re aftermarket springs to consult the spring manufacturer. Most of these are in the 5,000 plus round range (chrome silicon buffer springs in AR platforms can go well excess of 100,000 rounds depending on manufacturer). Depends wholly on the particular gun and manufacturer; some Glock or HK recoil springs have rounds in the tens of thousands on them without issue.

The key takeaway is that it’s almost entirely cyclical loadings which affect spring life through fatigue. Not simple compressional loading. So keep those mags topped off. And don’t spend your time worrying about it. If you gotta worry about something, worry about your not having gotten to the range enough to do some quality practice and training in that YOU are the most important part of the equation. And also the most likely part of the equation to succeed or fail. So get off your butt, do some quality training, and get out there and shoot and have some fun. Make time for it.”