Hello , I'm new to the forum and a new 1911 R1 owner .
I have a question about buying mags and parts for this weapon .
I see all kinds of aftermarket parts and all they say is they fit 1911s , are all the 1911 mags , handgrips , and so on interchangeable ? Thank you for your time

Welcome to the Remington Owners Forum Jim !!

Almost all aftermarket 1911 magazines and grip panels will fit the New Remington R1's.

But some parts such as night sights and internals may not...so shop accordingly.

Hello. Welcome!

Shooter13 is correct, the vast majority of 1911 "add-on" parts should interchange easily. Magazines for a Government Model of any brand will fit a full-sized Remington 1911.

There are some weird things like replacement sight dovetail cuts and beavertail grip safeties (which may need to be fitted) and maybe an internal firing pin safety system, firing pin, extractor etc. which you would have to check to ensure compatibility but Shooter13 is right on the money.

Thanks for the backup sir...

Mags and grips for government or commander models are all the same. Mags and grips or Officers models are not.
As was said earlier, sights are different from one brand to the next as well as within the same brand.
Also there are thin grips as well as standard. The grip screws and bushings are also different.