Your Browser is Outdatedcan the handguard be upgraded to fit a ten inch handguard? — 3 Answers
Yes, the R&D Precision PW9 9mm Gen 1 Bufferless Upper Kit is compatible with most standard mil-spec AR-15 components and aftermarket parts (such as handguards) but will require modification due to the forward charging handle.
You can physically remove the handguard and install a 10" handguard, yes. However, to manipulate the forward ambi charging handle, the handguard would need to be custom/modified to accept the necessary charging handle components (essentially an op rod that appears to enter the upper receiver where a gas tube would normally go).
you would probably have to get a proprietary handguard from them.