Crosman 3622 Hammer Tune Secrets

In this post we’re exploring some Crosman 3622 hammer tune secrets. Why secret? Well, the 3622 actually incorporates a hammer spring adjuster, even though it’s not an acknowledged part of the product specification.

And as every interested airgunner knows, adjusting the hammer spring tension on a PCP can give it a range of very different performance personalities.

With the 3622 you have the choice of a hunting power tune that gives around 10 shots at an average of 18.16 Ft/Lbs. Or a plinking tune of 50 shots at an average of 12.82 Ft/Lbs – and many variations in between – all while shooting the same 14.3 Grain pellets.

So how do we access the 3622’s hammer spring adjuster and what are the results when we do? Let’s find out…


Crosman 3622 Hammer Tune Secrets – Finding The Adjuster

It’s here! Hidden in plain sight, just where you would expect to find it. However, it’s immediately clear that the buttstock needs to be removed to gain access the the adjuster.

Crosman 3622 PCP Air Rifle Test Review

First ensure that the gun is unloaded, un-pressurised and safe! Now you’ll need to remove the safety. That’s done by pulling out on the sear spring extension and allowing the safety button to drop clear.

Then remove the two-piece stock. The forend is held in place by the two small screws.

Crosman 3622 Hammer Tune Secrets

Then you can remove the Phillips screw holding the rear part of the stock in place. I found it best to then replace the front part of the stock while working on hammer spring adjustments. Like this…

Crosman 3622 Hammer Tune Secrets

With the rear part of the stock removed, the hammer spring adjuster is now clearly visible. It’s turned using a 3/16-Inch Allen (hex) wrench.

Or at least it is once you have loosened the machinery adhesive holding it in place! I dropped a little WD40 onto the edge of the screw to soften the blue Loctite a little…

Now we can see the hammer spring and the adjuster. It’s just a simple screw.

Crosman 3622 Hammer Tune Secrets

So, having cleaned off the remaining dry Loctite, I returned the spring into its position and rotated the adjuster until it stopped turning. That set the hammer spring “full in”. That is with the maximum hammer spring tension.

Before examining the results, it’s necessary to say two things.

One, this exercise was undertaken on a different 3622 from the one tested in our comprehensive HAM Review. So the shootdown test data shown there does not exactly match that generated in this exercise.

Second, the Crosman 3622 is an unregulated PCP. So there’s no way that we will achieve a flat shot curve with our tunes. What we find is a variety of curves of FPS and power. Which curve is best? That’s a matter of personal choice…


Crosman 3622 Hammer Tune Secrets – Full In

Having set the hammer spring adjuster right in, I filled the gun to 2,000 PSI with High Pressure Air and then shot it across a chronograph to record Muzzle Velocities until they dropped below 500 FPS.

All testing was done using the 3622’s “natural” diet of Crosman Premier Hollow Point pellets. The results enabled the generation of curves for Muzzle Velocity and Muzzle Energy.

That was the protocol for each test with different hammer spring settings. Let’s look at the results!

With the hammer spring adjuster full in, Muzzle Velocity started at 775 FPS and dropped away rapidly thereafter. Nothing too surprising about this: the gun was “flat out” at this setting.

As we can see from the graph below, Muzzle Energy peaked at 19 Ft/Lbs and dropped away. 32 shots were made before pellet speed dropped below 500 FPS at this setting.

Crosman 3622 Hammer Tune Secrets

So, full in is the “hunting power tune” setting for the 3622. The result is 10 acceptably-consistent shots at an average of 18.16 ft/Lbs using the 14.3 Grain pellets. HAM takes an Extreme Spread of 40 FPS as a definition of “acceptably consistent” velocity.


Crosman 3622 Hammer Tune Secrets – Half Turn Out

Next I rotated the hammer spring adjuster by half a turn and repeated the process.

Crosman 3622 Hammer Tune Secrets

The results this time were 15 acceptably-consistent shots at an average of 746 FPS and 17.68 Ft/Lbs.

Crosman 3622 Hammer Tune Secrets

This would be another good hunting tune if you wanted a few more consistent shots.


Crosman 3622 Hammer Tune Secrets – One Turn Out

OK, no surprises here. Now the adjuster is backed-out one full turn from full in.

This time we see 16 “consistent” shots at an average of 735 FPS. That’s an average of 17.14 Ft/Lbs.

Crosman 3622 Hammer Tune Secrets


Crosman 3622 Hammer Tune Secrets – Two Turns Out

Now we’re at two turns out.

Crosman 3622 Hammer Tune Secrets

Now we have 22 shots at an average of 717 FPS. That’s an average of 16.34 ft/Lbs.


Crosman 3622 Hammer Tune Secrets – Three Turns Out

Backing-out further, the velocity and power of each shot continues to decline. The trade-off is more usable shots.

Now we’re up to 25 acceptable shots at an average of 703 FPS. That’s an average of 15.7 Ft/lbs of Muzzle Energy.


Crosman 3622 Hammer Tune Secrets – Four Turns Out

Now we see 30 acceptable shots with an average of 680 FPS. That’s an average of 14.67 Ft/Lbs.

As you can see, the shot curve is flattening-out considerably now. As a “happy plinker”, this is probably my personal preferred tune for the 3622.


Crosman 3622 Hammer Tune Secrets – Five Turns Out

This is as far as we go, folks.

Crosman 3622 Hammer Tune Secrets

In my opinion, the curve has now become a little too extreme. With a starting velocity of 600 FPS, we only have about 8 “consistent” shots within a 40 FPS Extreme Spread from the first shot.

However, we do have no less than 50 shots before reaching our 500 FPS minimum.

Crosman 3622 Hammer Tune Secrets


Crosman 3622 Hammer Tune Secrets – Conclusions

As we have seen, there’s a wide variety of “shooting personalities” you can give to your Crosman 3622, just by adjusting that “secret” hammer spring adjuster.

From my perspective, the best result is to be found somewhere around four turns out from “full in”. And, surprise, surprise – that’s where the folk on Crosman’s Bloomfield, NY production line choose to set the guns that are shipped-out to us. How about that!

But the 3622 does give us choices and you can set it to your personal performance preferences, just so long as you know about that “secret” hammer spring adjuster. Enjoy…

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Crosman 3622 PCP Air Rifle 0.22