AICS 3 or 5 Round .300wm 3.850" Length Long Action Steel Magazine

Assume this will be compatible with any .300 WM, AICS equipped rifle, such as my Begara Premier Ridgeback in .300 WM?

Yes that is correct.

Will 270 caliber fit this magazine

No i believe you would want a 30-06 aics magazine and then need to bend in the feed lips for the magazine to hold the rounds in place.

Are these magazines compatible with the 300 prc

No sir, you'll need this magazine https://mdttac.com/300prc-mdt-metal-aics-magazine/

Will these work with factory loads. 28 nosler 162 gr hornady precision hunter.

I believer you will want this magazine in .338 LM with 3.850" length.  https://mdttac.com/us_en/mdt-metal-magazines-long-action.html.  I would double check and ask MDT themselves about your .28 nosler just to be sure.

Does this magazine fit a Magpul hunter 700L stock and the 7prc cartridge?

if your magpul hunter stock takes AICS magazines, yes it will.  You may need to bend the feed lips slightly open to get the rounds to sit high enough to feed properly.

Will this work in the Ruger American GO Wild chassis chambered in 7mm PRC?

if your ruger american takes aics mags, yes it will.  you may need to bend the feed lips open a hair so the rounds sit up high enough.

Just got my stock with M5 DBM for a 7mm rem mag Christensen Ridgeline, is this the correct magazine?

Yes it is.

Will rem700 magazine work with 7mmPRC am mo

yes this 5 round aics mag will work, you may need to just bend the feed lips open a hair so the rounds can sit up high enough.

Will this work for 7saum built on a long action?

yes but you wiill need the bullet to have at least a COAL of 3.1 for reliable feeding per MDT. 

I need a mag for a 7prc in a masterpiece arms chassis is this the right one?

Yes it is, you will need to bend the feed lips open so the rounds sit high up enought to feed.

Will this work for 7PRC with the GRAYBOE HUNTER M5 DBM - REMINGTON 700?

yes it will but per MDT, you may need to bend the magazine feed lips open a hair for the 7mm PRC round to sit correctly in the magazine and feed.

Will the magpul aics LA mag work in your stocks?

yes it will, though i have heard from customers that magpul mags can be finicky at times but if they are AICS style then yes they will work.

Does this AICS mag fit all your long action bottom plate grayboe DBM plate?

This mag fits the long length M5 DBM's, not the CIP length.

Will this mag work for 7mm PRC in a Magpul stock

yes it will but you may need to open the feed lips of the mag a bit for the rounds to sit high enough to be picked up by the bolt.