What componants would you use if you were building the best AR10 you could find Ideally steel lower and upper would be cool!
Something on the order of a 26 inch barreled 6.5x47 or Creedmoor.
I started with the DPMS LR-series of AR-10 clones and have no regrets. The Knigts SR-25 is probably a better rifle but it doesn't have the diversity of cartridges and it costs a bunch more. DPMS and Knights use the same magazines. Armalite holds the AR-10 trademark. Several other companies offer clones with various degrees of compatibility. Accurate Systems offers a number of chambers in custom AR-10 rifles. Anyone can assemble an AR-10. Making them shoot reliably is what you pay for. Not all AR 10 clones have compatible uppers and lowers. Magazine compatibility is especially confused between brands using M14, FAL, and a couple of ad-hoc styles.
I think you'd find a steel upper and lower less cool than you think after you carried it for an hour. In all AR design all gas pressure is contained in steel. (bolt, barrel extension, barrel , gas block, gas tube, bolt carrier). The aluminum forgings only carry mild forces and are plenty strong. An AR-10 action is about 1 lb heaver and 1 inch longer than an AR-15, but they usually have heaver barrel contours. Handgards are larger diameter. Stocks , handgrips, and trigger assemblies may be the same as AR-15 parts but not necessarily.
Look at the exploded parts diagrams on the Armalite and DPMS websites. to see what parts are needed. Functionally it's nearly identical to an AR-15. There is less standardization between various brands of AR-10s as between AR-15s. You won't save any money on the upper if someone offers what you want by buying it as parts. You can just buy a 6.5 Creedmoor ready to go from DPMS. (as long as you want a 24" heavy barrel). I don't know anyone selling a 6.5x47 Lapua AR-10, though I'd expect it to work well. The 6.5x47 does have a higher pressure rating than the 308 cartridge.
I don't care for the DPMS triggers, stocks, and handgrips. Those are interchangeable (mostly) with AR-15 parts. I buy most of the parts except the stripped lowers on the web, and buy the stripped lower at either local gunshows or gunshops. (that saves ffl charges and hassles) I buy DPMS lower parts kits and scrap the trigger and handgrip. That's the cheapest way I've found to get what i want.
In my opinion the 6.5 Creedmoor has the best performance (range, downrange energy, and wind deflection) of any commercially offered AR rifle. Its essentially the 260 Rem shortened enough to allow 140 VLDs to shoot from a 2.85" magazine. The 300 SAUM has more energy for practical hunting distances but it has poorer wind performance. It's limited by the 2.85" magazine too. 190 SMKs are about upper legth limit. If you don't need VLD bullets it's a good cartridge.
Beware. AR-10s are at least as addictive as AR-15s.
