The Gen4 Glock 17 is part of the voluntary recoil spring assembly exchange.
Glock issued an announcement about a voluntary recall or exchange program for the recoil spring assembly on all of Gen4 pistols sold before July 22, 2011. In the announcement sent out to Glock armorers, the company stated their product development team modified “various elements” of the recoil spring assemblies to “…ensure each pistol’s performance meets the company’s demanding standards.”
The Gen4 Glock 26 and 27 pistols are not part of this recoil spring recall.
The recoil spring assemblies can be replaced by the owner of the firearm, and the firearm does not need to be shipped back to Glock.
The replacement part is free, and the complete instructions on obtaining the new recoil spring assembly is located at the Glock site.
There are a variety of different Glock Gen 4 recoil spring assemblies in circulation. Glock provided the following graphic to help identify which part you need:
Glock Recoil Spring Assembly ID Chart
Ever since the Gen 4 pistols started shipping, there have been complaints about reliability. Several discussion threads on the topic have been posted on various shooting and law enforcement web sites. It would appear that this voluntary exchange is to address these reliability problems.
The third generation Glock pistols chambered in .40 S&W and fitted with a weapon light were found to be unreliable by a number of police agencies. A number of people believe Glock introduced the new recoil spring assembly found on the Gen4 pistols to correct the third generation problems.
Surviving the Street: Guide to Concealed Carry of a Firearm
Essential information on concealed carry. This book has just the basics - not a lot of fluff to get bogged down in. Easy to read, Surviving the Street introduces the reader to the important information you need as an armed citizen.
The author presents frank information about self defense in a way that is easy to understand and use.
Other articles that will amaze you:
[...] voluntary recall on the recoil spring assembly of Gen 4 Glock pistols started on September 6 and affects all Gen 4 [...]
You’re back! Look forward to getting the goods on the goods. The Glock recall was very good timing as we are doing inspections on Glocks right now.
[...] seems Glock has experienced some reliability problems with certain springs and calibers (see Gen 4 Glock recall information here) in the Gen 4 guns. I hope the problems have been wrung out and the new G21 will run [...]