Hi Don, and welcome to the forum.
The feeding problem that you experienced can be caused by a few things.
First, is the pistol clean and properly lubricated? If it's tight and dirty, drag can get the cycle timing off. Dirt under the extractor can also cause problems.
The easiest to take care of is the way you grip your Luger when shooting it. It has to have a well supported grip that prevents the pistol from rotating (rising) off level. That means a grip about as tight as you'd hold a child's hand as you guide them across the street. Often by paying attention to the grip, you'll find the Luger will shoot more reliably. This is a likely cause of stovepipes.
The condition of the recoil spring within your magazine is next on the list. Mec-Gar magazines are the best on the newly manufactured market. If you want the base replaced, consider sending it of to Gerald (G.T.) and let him do a complete job on it.
There were different strength coiled springs used on the earlier DWM and Erfurt Lugers.
The Mauser Lugers used a main recoil spring with (I believe) 20 or 21 turns. Earlier WW-I Lugers had 17-18 turns... Wolff sells a range of springs for the Luger:
http://www.gunsprings.com/index.cfm?...s&cID=1&mID=38
It's sometimes worth trying alternates if the first things don't work...
Marc