Have a friend who wants to free float his DPMS LR-308

How can I tell which Gen it is (serial 168xxx)

And can I use a std ar15 wrench for it?

Any recommendations on rails?

Thanks

I like Lancer carbon fiber and JP free floats.

You'll need an LR-308 barrel nut wrench.

That an LR-308, not a G2.

OK Thanks, so the handguards/nuts are different for each, correct?

If you use a JP float tube, you can use a standard AR15 barrel nut wrench because JP made their nuts that way, which is nice for smiths.

You also get an AR15-sized float tube on a large frame gun, instead of a beast-sized float tube meant for Goliath's hands (I'm 6ft).

Does his rifle have an LR-308, AP4 v1, or AP4 v2 upper?

There are 3 different rail heights between LR-308 and AP4.

I didn't believe this at first, but I have owned all 3 and have both AP4 uppers in my gun room right now, measured both and they are different, even though they look the same.

You need to know that height when selecting rails if you put any rails on the float tube ( I didn't.)

I prefer the Midwest Industries SS rails. They also have Keymod and Mlok versions as well. $200 but I have found them around $150-160.

Does he know about the high vs low version of his upper receiver? Not all hand guards will line up so he needs to determine what size he has before ordering.

Is there a measurement point and reference heights as to which upper he might have?

To me it almost looks like a billet upper (hexagonal-ish)  I'll upload a pic here in a bit


Attached File




My only experience with the AR10 is Armalites, sorry for all of the questions.

He asked me to hook him up with a float rail, and a future 6.5C barrel.

I told him that he needs to upgrade that Barska 'sniper' scope first

Whenever I see Chinese or Barska optics with pot metal rings with single fasteners on an AR10, I wonder if my advice is going to be of any value moving forward.

You can measure what kind of upper it is by taking calipers to the rear tang of the rail just above the charge handle.

He told me the Barska is a good 'sniper' scope because it has all those fancy knobs on it, and the reticle lights up




I never said all my friends were smart