In August of last year a member on another forum I’m on mailed me his drop-in KKM barrel to do some testing in my Gen4 Glock 19.
I didn’t shoot too much because there was a pretty bad cross wind of ~5-10mph. The KKM barrel did very well from what I was able to do, though.
I only shot 124gr +P Gold Dots and Federal AE9 for testing, but I didn’t take any pictures of the AE9 because the horizontal spread was poor. Also, I reduced my groups from 10 shots to 5 shots. 10 is “industry standard” with a rifle but with so many points of contact for stability it’s more logical. 10 rounds of slow, accurate fire with a handgun is mentally draining and takes a lot of stamina. 5 rounds is sufficient for testing.
Here are the first 5 rounds of GD’s through the KKM barrel at 25 yards/75 feet. 3" - not too shabby:
It’s a good group, but it was impacting pretty high on my target. At 25 yards with CAP sights and the KKM barrel, my groups were about 1.5 - 2 feet high. If this were my barrel I would consider getting different sights to account for that major shift of POA/POI.
I took a quick break from that to shoot my M&P15-22 for a bit. After that, I went back to the Glock and decided to push myself out to 50 yards/150 feet (!!). How bad can it be?
Not too bad indeed. A hair over 7" at 50 yards? I’ll take that.
After that I felt like I was in the zone, so I moved back to 25 yards/75 feet and posted this final group with the KKM barrel. 5 rounds in 2.6"
For this group I was holding the top of the sights at the base of the black circle, so it’s about 6" high from POA.
At the end of the day I swapped the KKM out for my OEM barrel and shot a final group at 25 yards. My previous best group was 4" with AE9 FMJ, this is slightly under that with GDHP: 3.7"
I think the KKM barrel is a very good purchase. I saw groups of 4-5 inches shrink to sub-3 inches. For $165 I’ll take that improvement. I was also very impressed with it’s performance at 50 yards; it really makes you rethink how far you COULD make solid hits if you were forced into that situation (how long is an aisle at your local big box store? 100 yards? More? Not that you would ever engage that far, just some food for thought considering some of the environments we’re all in during our day-to-day lives.).
Some people don’t see so much change from drop in barrels like the KKM vs. OEM barrels, especially on a compact gun like a Glock 19. But, I also suspect they’re not shooting at the limits of mechanical accuracy the gun is capable of. I think out of the box the Gen 4 9mm Glocks are some of the most accurate polymer guns that are currently on the market. Add improved sights, a drop in barrel and some good ammo and you get a sub-$1,000 gun capable of 1911 level accuracy but with superb reliability.