I’m curious what the weight difference is between two rifles that are exactly the same with the only difference being one is a 14.5" carbine while the other is a 16" mid length. Anyone know how much weight difference there would be between the two rifles AND how drastically would that weight effect the balance of the rifles?
Actual m4- 6.36 lbs
http://en.m.wikipedia.org/wiki/M4_carbine
6920 - 6.9 lbs + what? Maybe .2 for longer handguard & gas tube of a mid length?
http://www.coltsmfg.com/Catalog/ColtRifles/ColtLE6920Series.aspx
Use google, you can get a better answer if its really that important.
You can use this AR-15 weight calculator to help get you the answer.
Depends on barrel profile. With a heavier profile barrel there will be more weight in the amount lost. In a pencil barrel you probably won’t really notice anything. Heavy barrel maybe. Remember unless you SBR it, you have to pin/weld the device which ultimately needs to be longer to make the 16in mark.
To put it this way, a 16in LW BCM barrel is only a little heavier than a 10.3 dd barrel. Why, because of a lighter gas block due the .625 block area and thinner barrel from there to the muzzle compared to a 10.3 which is a normal gov profile.
Now will a 16in pencil barrel be lighter than a 14.5 gov barrel, def yes. Just like a 14.5 pencil barrel will be a whole lot lighter than a 16in gov barrel and so on.
IMO barrel profile is what will save weight in the end, compared to losing only a tiny bit of weight with a shorter barrel.
1oz or less depending on the muzzle device used between them
https://spreadsheets.google.com/spreadsheet/lv?key=0Ajl2UPK0UHPsdHNVX2tBak9OS29HR2ZrRFBhUVpYMVE&hl=en
Very curious as to why you’re concerned? Are you building a rifle for a specific purpose? If so, what is that purpose?
Answers to the questions above are going to lead to a much clearer answer than simply a numerical weight difference, and how far back or forward a balance point would shift (which would be no more than an inch or two at most).