Lengthen S&W 'AR' M&P butt stock by 1-2".

I also find the AR stocks to be too short. For myself I have gone with Magpul stocks. MOE the cheapest then add their extended butt-pad.

I think it is the STR stocks that have a longer length of pull? Then you can add the extended butt pad and be get even more LOP.

I also have long arms.

My current in progress AR build is going to have Carbine adjustable stock. As with you it is going to be a little short for me but such is the compromise of the Carbine.

I am considering a Magpul MOE SL stock. This is where going to a gun show will come in handy. I am going to take the gun with me and try different buttstock on it until I find one that is just right (or most likely the best compromise fit).

I do plan on building a rifle with one of my other lowers. In addition to having a longer barrel with rifle length gas system I am going use a fixed stock. As my planned uses for it will be target shooting and hunting the longer length will fit me better making accurate shooting easier.

I'm 5'11" and kinda long necked.
Ran a Magpul CTR with .5" pad. Was OK.
I yanked all the Magpul off my AR and went back to factory.
Not a big deal IMHO.

Summertime, yeah it's a little short. Wintertime it's perfect.

The short stuff is meant I guess, to be shot in a more fwd facing stance.

Magpul MOE rattles. If going aftermarket get a CTR. It's a little nicer IMHO.
I've had two or three of them. Still not perfect.
Since my AR rattles and gets treated like a red headed stepchild, the factory plastic clunking about doesn't bother me.
And I like the look.

The UBR Gen 2 has better than 15" LOP when extended. That's close to 2" more than an M4 stock.

It's heavy and expensive though.

Just square up when shooting, Russian style.

By way of the kind and gentle NCO who provided my instruction, it seems wrong to not have my nose touching the charging handle and to "chicken wing" the right arm.
So, I'm likely to be as unhelpful as those foolish web sites. Gee, anyone buying a extending pad for an AR wants to know its thickness--how do they sell this stuff? But, beyond NYC journalists, who is buying a recoil-reducing pad for an AR?

Magpul ACS is a bit longer.

Look into the Vltor A5. It's longer than the A2 stock fully extended, and it increases reliability, gets rid of bolt bounce, and some more stuff I can't remember.

Try a pistol grip with a more vertical angle andv if you're using a scope, push it forward. Both will make the stock feel longer. Lengthening the stock much more than it already is will make the AR feel awkward

I'm 6'5". I put the magpul acs-l on mine and it's just right now.

I switched all my carbine stocks out for Magpul ACS-Ls for this same reason. They have more than enough length for me... I usually run them one click in from fully extended when shooting NTCH from field positions. The A2 fixed rifle stock is the perfect length for me too.

I am a similar size to you and also turkey neck out a lot farther than most people... usually if I pick up someone else's rifle, the ocular housing of the scope will be in my eye socket.

I'll never stop shooting a traditional bladed stance--too old to have a different stance for different rifles. I've never felt the need to square off the front of my non-existent bod armory towards a deer or coyote and I don't want my nose anywhere near metal when I pick up my 454 Win mag.

Extended butt pad on a Magpul CTR gives me the ~14-14.5 LoP I desire. I actually use the 2nd to last position on my AR10.

Mike

6 footer here. With average-long arms. After shooting ARs for 35 some odd years I no longer like anything longer than the old A1. In fact, I prefer the 3rd notch on the collapsible or the Magpul fixed carbine stock. Even have one on my Colt Sporter Target 20 inch with extended mounted 3-9x scope. Different strokes. Guess we should be glad to have so many choices, eh?

M