About 2 months ago I decided to purchase a police trade-in Glock 21 Gen 4 so I could write this Glock 21 review and test the hardness of the slide and barrel on our YouTube channel.
We didn’t want to pay full price on a Glock we were planning to permanently scar and found a pretty good deal on a retired LEO Glock and bit the bullet.
We didn’t know exactly what to expect condition-wise but anticipated the worst. It didn’t matter much to us either way but we were pleasantly surprised- to say the least- at what we got.
Glock 21 Review- Inside The Box
The Glock 21 Gen 4 came to me in its original box, which was a little worse for the wear, and was missing the extra back straps that normally come with a brand-new purchase.
It also came with only one magazine, instead of two, but the cleaning rods, manual, and most importantly, the Glock itself, was included!
One of the best surprises right out of the box was the upgraded metal night sights instead of the stock plastic junk you find on new Glocks.
I’d wager that’s at least a $125+ freebie and helps make up for the missing back straps and extra magazine.
Glock 21 Review- Unboxing & Bore Test
We did a borescope exam in our unboxing video that I’ll list below and discovered some harsh scratches that were probably caused by somebody using a steel bristle brush and going to town on it!
Other than that, the condition of the lands, the rifling, and the crown suggests it hasn’t really been fired all that much.
Somebody suggested in the comments of that video that it probably hasn’t seen more than a thousand rounds, which I tend to agree with.
The slide of the Glock 21 Gen 4 shows the most signs of holster wear and the matte black finish that is present on a lot of Gen 4 Glocks is very prone to scuffs and scratches.
There was only one really noticeable scratch on the left side of the slide and some worn-down areas that made the finish look a little “blotched” in places.
This may bother some but it wasn’t really a dealbreaker for our purposes.
Glock 21 Review- Range Test
The Glock 21 passed its function test perfectly at the range after putting nearly 150 rounds downrange of the cheapest ball ammo we bought some years ago.
Thanks to the large and heavy slide, the recoil felt very manageable despite its not-so-great factory trigger (which was at least well broken in and smoother than when new).
There were no failures of any kind and the magazine still has plenty of life left in its spring. Unfortunately, we didn’t have any specialty rounds to test with but Glocks are known to eat just about anything you feed into it!
Glock 21 Review- Hardness Test
After a bit of fun at the range, we took it back home to test the hardness of the slide and the barrel.
We have two unique machines for doing tests on case hardness and base metal hardness.
The first machine is a UCI Ultrasonic hardness tester that can test case hardness (which is the hardness imbued into the surface of the steel using methods such as nitriding, nitrocarburizing processes like Tenifer & Melonite to name a few, and various other processes that infuse carbon into the surface of the metal to give it a case hardened surface).
The hardness of non-case-hardened steels can also be tested by the UCI method. With case-hardened steel, like on the Glock, you’ll need to use an analog hardness tester which is a big heavy machine with a diamond indenter.
Check out the video below to find out how hard the metal on a Glock really is!
Conclusions
Ultimately, we think buying a retired Glock 21 Gen 4 was a great idea and will serve a home defense role now that we’ve wrapped up all of our tests for this review.
It’s great for training purposes too and most of all you don’t have to worry about scuffing it up since it most likely already has some wear and tear.
We added a few marks of our own under the slide and on the barrel during our hardness testing to show you how hard a Glock really is so you don’t have to!
