Unable to get the 7th round in the magazine even with the Maglula loader. The first six took a lot of pressure, I don't know how much pressure the finger on the loader will take but I felt like I was taking it to the max when loading the 5th and 6th rounds. No way on number 7. Just ordered a MagGuts +1 Kit for it. Hopefully that will work better. Also have five of 6 round .40 mags and of the ones I have tried, they all took 6 rounds, although not easily. Anyone tried the MagGuts kit on their .40 magazines?

Get it loaded and keep it loaded. The spring will relax and be more forgiving as time passes.

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S&W factory revolver armorer

That is the problem. Unable to get the 7th round loaded.

Get a more manly friend that shoots to load it ! Anyhow if you have cleaned it but kept it dry inside and you returned the mag spring with the right side up and turned correctly its more than likely your issues .

You do understand the standard flush fit mag is a 6 rounder right ?? The extended mags with the x grip gap filler is the 7 round mag right ??

The mags are all new, both the 6 and 7 rounders. Have not had them apart. I weight about 245 and I can put a lot of weight on that loading tool, but I do not want to break it. And yes, I do know the difference between the 6 and 7 round mags. Got my first gun 55 years ago. Have owned and shot well over a hundred guns since then. So it appears you are dead wrong about the most likely issue.

Factory Shield mags being tough to load the last round has been an issue since they first came out back in 2012. Not getting the last (6th or 7th) round loaded at all usually means something isn't put together right.

Once in a while, a mag gets put together from the factory with the spring backwards (very rare). It would be worth checking.

Yes, I agree that is a possibility. If it does not loosen up soon I will disassemble and check for that. Thanks much.

Although mine is 9mm (and a 1.0) I have the same issue. Doesn't matter is it's the 7 or 8. I put most of the rounds in my my Uplula, then insert the last round with just my hands. Yes it's tight. When at the range, I just skip the last round as I have a few extra mags.

Just finished a short shooting session with the Shield. Used three 7 round mags and one 6 round mag. Two of the 7 rounders and the one 6 round loaded full with no problem. The 3rd 7 round mag will only load 6. So I disassembled it and looked at the spring. Did not remove the spring from the follower as it appears both ends of the spring are identical. Maybe a reversible spring? Never heard of that, but maybe S&W makes them this way. Reassembled the mag and no change. Will only load 6. Something is wrong as all the other mags load fairly easily with the Uplula loader. I shot a 1911 after the Shield and the Wilson 8 round .45 ACP mag loads much easier than the Shield mags.

When I picked up my first Shield M2.0, a 9mm, I couldn't believe the amount of effort it took to completely fill the magazine. Even using a friends Maglula it was a bear. I actually found that the simpler: Pin on misc things type loader was easier to use. Several are made using a 3D printer that cost less than $10.

Springs do not "relax, weaken, or become more forgiving" just from keeping the mag loaded all the time.
That is an "old wives tale". Springs relax and become easier to load by full cycles, load/unload. Over and over again.

I was told that as a kid by my career Army dad and older brother that was a detective. Others had told them that.
Rotate your mags, don't leave them loaded more than a few months.
But now we know better. Ask anyone with an engineering degree or a machinist.

Patrick Sweeney, who has engineering degrees, and is a custom gunsmith, competitive shooter and LE instructor, said an old lady brought a bunch of guns into his Michigan shop and wanted to sell them. Her husband had died and she wanted to get rid of the collection. There were thousands of rounds of ammo, all loaded in magazines. She said they had been loaded for 30 years. Sweeney said the mags all worked fine when tested later.

Once again, keeping mags loaded (spring compressed) does nothing to relax or weaken the spring.
What does is loading and unloading them over and over, either unloading by hand, or by shooting the ammo in them.

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U. S. Army Veteran

If it is a new gun and/or factory magazine, I'd contact S & W and they'll probably just send you a new one. You seem to have gone through all the usual steps to figure out the problem, let them deal with it.

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Alan
SWCA LM 2023, SWHF 220

OP, I’d maybe add (apologies if I missed it) that as you took apart the mag giving you trouble, did you take one of the others apart as well to compare the spring layout? At least that could answer if the bad mag’s spring was unique or not.

No, but I will. Ordered a MagGuts +1 replacement spring and follower so when I install that on one of the 7 round mags I will compare. Thanks.