I do the following to test the recoil spring tension:
1. Unload pistol and ensure that it is empty.
2. Point the pistol at the ceiling
3.
Pull the trigger and hold the trigger back (so the striker release don't catch the bottom of the striker and add tension to the recoil spring).
4. Pull the slide all the way back.
5. Hold onto the slide and slowly ease it forward.
6. If the slide goes into battery, your recoil spring is good.
7. If the slide does not go into battery, replace your recoil spring.
If your Glock 27 has "only" 2000 rounds shot through and experiencing issues with "only" one type of ammunition, I would first try different brand of ammo. If problem goes aways with different ammo, then I would be inclined to suspect the ammo, not the pistol.
If the problem persists with different ammo, I would next check the magazine spring/mag follower. If using a different magazine (preferably new/newer) don't reproduce the feeding issue, then I would investigate the magazine spring/follower and replace as necessary/worn. I prefer to replace my magazine springs with Wolff 10% extra power springs. After spring replacement, I replace the follower if I have feeding/chambering issues.
I shoot both factory and reloaded target loads and prefer OEM factory replacement for recoil springs. If you want to "customize" the recoil spring rate for a particular reload, you can buy appropriate spring rate recoil springs but keep in mind that you may be "locked" into only shooting that particular load for your pistol to reliably function.