Can ANYONE explain this AR10 Buffer Issue???

[Razorhunter]

Guys,
I've got a 21" Noveske AR10 upper, and Noveske told me that I must use a RIFLE BUFFER with this gun, IF I choose to use a stock such as the Magpul PRS, or a Fixed A2 stock.
However, I see on Noveskes website, that ALL of his complete 7.62 AR10 rifles come with H3 buffers, and collapsible LMT Sopmod stocks.
I am wondering HOW this buffer combination ALSO works????
How can a 21" AR10 upper work with the following TWO combinations: ????

1. Rifle buffer, rifle buffer tube, and Magpul PRS or Fixed A2 stock
OR!

2. H3 buffer, 6 position buffer tube, and LMT Sopmod or other AR15 sliding buttstock


????

I have heard the "H3" buffer is the SAME thing as a "Carbine buffer" for an AR10.
IS THIS TRUE?

Can ANYONE explain this? This is the last dilemma I've got when it comes to AR10 buffers/stocks, and I need to get this cleared up. I've asked these questions numerous times on other forums, and cannot get any CONFIRMED answers guys. I even once asked Armalite, and never got a confirmed answer. John Noveske is literally impossible to catch in the shop these days. He's only stopping by the shop a couple/few times each week, and I've tried numerous times to get him (still trying).
I figure someone has GOT to know the answers here? Would really appreciate it guys!
Thanks!

[SHIVAN]

An ArmaLite AR-10 rifle length buffer is 5.215" long which allows for use in a standard AR-15 A2 receiver extension.

The standard AR15 H3 buffer can not be used with a standard AR15 6-position receiver extension.

I suspect that if you look at: Noveske AR10 H3 (http://noveskerifleworks.com/cgi-bin/imcart/display.cgi?item_id=762buffer&cat=10&page=1&search=&since=&status=), you will see that it requires a Vltor AR-10 extension, or alternately a commerical ArmaLite AR-10 Carbine extension.

A Vltor AR-10 extension is longer than a standard AR15 extension, which means it will accomodate the longer AR15 H3 buffer.

I prefer to use standard AR15 parts were possible. So I use AR15 extensions all around, and I have Clint aka "Slash" (http://www.ar15.com/forums/topic.html?b=7&f=120&t=229073) make my buffers to fit my AR15 tubes for use on my AR10's.