I had hoped that locking back the slide would be easier after a few hundred rounds. It almost seems to be a two stage compression to the spring. Compared to the effort to lock back my Glocks it is at least 3-5 times more difficult to work the slide. Anyone know if thus us normal?

I suspect a problem with your Recoil Spring Assembly (RSA). Is it installed correctly?

It’s unlikely that either the slide stop notch or the slide stop lever are out of spec.

Does it lock back after the last round from a mag?

Are you talking about racking the slide back with an empty magazine in the pistol, so that it will lock open? Or are you talking about pushing the slide back until you can press up on the slide stop, locking open the pistol? Both are manual procedures, but it's easier for me to rack the slide with an empty magazine in the gun so that it locks open, than it is for me to push the slide back with one hand and push up the slide stop with the other. For one thing, it takes more coordination to do the latter, which I don't have in abundance, and it's harder to hold the gun and move up the slide stop while pushing the slide back until it's in the right position.

It's been a while since I've had a Glock or a Shield 9mm, so I can't really compare them from memory, but the RSA on my Shield 45 seems much more "stout" to manipulate than on my Ruger SR1911 CMD. I guess they have to be on the smaller, shorter guns to overcome the inertia of the slide's rearward movement under recoil, etc.

If your Shield is operating and ejecting reliably, I'd say it was normal. You don't want too light a recoil spring, or it will end up damaging your pistol. Too heavy and you'll have performance issues.

Maybe you just need to shoot it some more, for it to lighten up a bit.

I have two Shield 9s. I feel what you're experiencing is "normal" for Shields. I always, when racking give an extra hard push just when if feels the slide is back. That extra 1/16 of an inch is required to be able to push the slide lock up.
The poster that suggested putting an empty magazine in the pistol and then racking it won't require that extra 1/16 push.
I feel Smith & Wesson should have addressed this a long time ago.
Stay safe out there
Poli Viejo

I have a Shield 9. My recoil spring assembly has 2800 rounds on it, and it hasn't loosened up hardly at all. It is still very difficult to lock back, especially during reassembly after field stripping. So don't expect that locking back the slide will get easier with use. If you want to make it really easy to do, get a Handi-Racker, the best invention since the Uplula magazine loader. Here is the website for the Handi-Racker:

Safest way to rack your pistols Handi-Racker

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What, me worry?

9mm & 40 Shields are virtually identical & use the same recoil spring assembly. They're the most difficult subcompacts I have ever tried to rack & they never loosen up. The "stacking up" at full compression is noticeable. Previous suggestions already posted here are excellent.
Also, the 45 Shield uses a different RSA & is noticeably easier to rack.
The best suggestion is to use an empty mag to automatically lock the slide back.
As was noted by another member, a weaker RSA can help quickly deteriorate or destroy the gun with full power ammo.

Mine became very manageable after approx 2,500 rounds. And, now after 8,000 + it has really gotten very easy to rack for this 83 year old Sr. citizen.

yes, I too have a Shield 9, and yes it is rather difficult to lock the slide back as well. I have learned to manage it by being extremely deliberate when pulling the slide back or else it will not happen. When I am cleaning and have any oil on my hands it is that much more difficult...have to grab a rag to execute this maneuver.
My wife cannot even come close. Again, throw a mag in...

This is one of the problems with small guns.

Because of the reduced mass in the slide, they need a stronger recoil spring. Because of the stronger spring, they are harder to rack by hand.

The Shield has less extra movement in the slide than some other guns. If S&W had built in 1/16" more rearward movement, the slide would be a lot easier to manually lock back. Alas, they didn't do that. So, it just requires good technique and practice.

It will become easier with time. Not because the spring loses power, but because you get better at it.

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Freedom isn't free.

Assuming the gun fires and locks back normally (which you haven’t yet confirmed), maybe it is a question of lack of strength and/or technique. If you are trying to lock the side back manually without a magazine on the gun, try this technique:

Assuming you are a right handed shooter, grip your unloaded Shield in your right hand so your right thumb can push directly up under the slide stop lever. This is not a firing grip.

Grasp the slide with your left hand in an “over-the-top” manner to get the most and strongest contact with the slide. That is, the bottom of your left palm against the left side of the slide with your left thumb also on the left side of the slide. Your other four fingers go on the right side of the slide. Grip tightly. Keep the gun pointed away from you.

Now, before retracting the slide, push up on the slide stop lever with your right thumb, just as the magazine follower would be doing if there was an empty mag in the gun with a closed slide.

Using your left hand, and firmly holding the gun steady with your right hand, run the slide smartly rearward. Your are duplicating what happens when the gun fires the last round from a magazine.

If this doesn’t work, have someone else try it while you watch. It is not possible for the gun to fire a last round and have the slide lock back normally and then not be able to manually duplicate that action without a mag in the gun.

When I first got my Shield I had to teach myself how to rack its slide and lock it to the rear! I was used to 30+ years of the thick slides of my M&P40c, Sig P229/P226 and HK P7M10. They were much easier to grip overhand than my Shield is, once I got that worked out the Shield is easy to rack now.

Buy some GT-5000 grip tape from Amazon and put it on both sides of your slide. It will make it much easier to grip while trying to lock it back.

It's normal. I just got a 2.0 full size and the effort between my shield and my 2.0 is quite obvious