Originally Posted by barth
I'd practice more with the P30 and dial up the speed.
You could do this or put a fitted or semi fitted barrel into the Glock which would negate the accuracy difference. By semi fitted I mean something like the Wilson Combat barrel, which is said to be drop in, but I've never heard of anyone that didn't have to do a bit of fitting with it. KKM makes a drop in barrel for Glocks that reportedly gives a pretty decent accuracy improvement over the stock barrel, though I've never used one, so I can't tell you.
I do understand your dilemma. I have a Sig P226 that's extremely accurate. I don't notice a big difference between the Sig and my Glock until I get to 15 yards and beyond. At 15-25 yards, the Sig is significantly more accurate than my Glock. This despite the fact that my Glock is fairly accurate.
Personally I think it depends on which gun you like better. If that's the HK, stick with the HK until you get more proficient with it. If it's the Glock, just replace the barrel.