Looking at shaving some weight. Carrying a middie HB 1:9 with a drop-in quad and various assorted doodads. I have a spare barrel I picked up in a swap, it's a legit M4-profile 16". I can shave a few ounces by dropping the A2 sight post (complete with standard sling loop, side-sling adapter, bayo lug, etc) with putting in a low-pro on the existing barrel, or using same low-pro and a cheap full-length free-float with the M4. The UTG "pro" rifle-length free-float is actually the lightest and cheapest I've found, and it's getting decent reviews.

I calculated the costs...gonna cost me about $25 for the low-pro block, and about $25 for the UTG free-float. I'll be doing the work myself, so there won't be any labor costs. Existing barrel is a Rock River, and it's a pretty decent barrel. The M4 is a Colt 1:7.

Should I save the hundred bucks, or save the half a pound?

$100 for a half pound of savings? What sort of doodads do you have on it? Can't you just pull off some accessories and possible get more weight reduction?

Already pulled the EOTech and laser sight off of it, lightened it up considerably. Going to swap out the "artificial daylight" 3-cell flashlight for one of those Surefire plastic jobs. I still like to see on those night-time hog hunts, but found the little red dots to be dead weight.

You may be able to outrun me to the mailbox, but I'm old-school. I'll outrun you to the next town, and do it in steelcaps while smoking a Marlboro just to piss you off while you're wheezing. Ounces add up to pounds, and pounds add up to sweat that's better spent on stuff you have to deal with...hence the reason I'm asking this question. Don't be a dick, just answer it.

In the immortal words of Cameron Diaz, "I'm just fucking with you, Ted!"

I got to looking at it, and I spend that much on Keystone and Marlboros in a given week. Seems worth it to me. On a semi-related note...inflation's a bitch, ain't it?

I apologize if my language offended anyone. Duck and cover?

UTG rails weigh a ton. Try something else if you're really looking to lighten up

If you really want to drop weight, just use all MOE stuff.

I like keeping mine light, so the Magpul stuff works for me although I know it's not for everybody. A TRL1s light and the EXPS-3 Eotech is all I mount to my weapon, and it is very managable.

The Ar15.com answer is to buy another reciver and build two uppers. Use the M4 lightweight barrel with the FSB & some plastic handguards with a red dot or some good irons and a second build with the RR HB with the floating rail and a low pro block and a scope. See, that was easy.
I'm running a drop in UTG carbine quad rail on one of my uppers, it's heavy but it's solid and has held up well. For the $40 I spent on it I've never been dissapointed.