Casper

6.5 Creedmoor can be formed from .308 brass too and the shorter case + longer neck fit better in magazines. I have had very good results with 140 grain Hornady Amax at 1,000 yards but the newer ELD stuff is probably better. Comparing box to box, you can't find any ammo in .308 that will hang with 6.5 Creedmoor and the prices are pretty comparable. If you reload, the price is pretty much the same unless you like to shoot cheap FMJs or pulls. I don't think it makes sense to build a large frame AR for anything except accuracy and if you want to shoot cheap surplus 7.62x51, you won't be terribly accurate as you eat up the accuracy life of your barrel. It doesn't make sense. In my opinion, stick with standard pressure bolts unless you want to hand load with small rifle primer brass exclusively. A high pressure bolt might pierce primers on LRP box ammo. You don't need to hot rod 6.5 Creedmoor to get to 1,000 so don't complicate your life. The standard AR15 accuracy trick works, free float handguards are key. I like the Aero M5E1 enhanced upper/handguard combo, usually in Quantum M-lok because it's cheap. Then get an Aero M5E1 lower and partial LPK to match. I have a recipe I like to build a ~budget M5E1 with all the little upgrades I want. With some smart shopping and waiting for sales, you can get a whole lot of rifle for under $1,500.

Well the M5E1 upper and lower are forged 7075. The handguards are 6061 and almost certainly machined from extrusion. The finish is hard anodized black, Cerakoat FDE or custom coated builder sets. One thing Aero doesn't do is proprietary ambi controls on the lower. Some fancy lowers have that but it locks you in to a single supplier with high prices. Beside the ambi bolt catch, I do ambi everything with drop-in parts on an Aero. I could add something like a BAD lever to give it an ambi bolt catch but I don't think it's necessary. The Aero M5 seems to be pretty much LR308 compatible. I think the only non-AR15 type parts in the LPK are the bolt catch and takedown pins. I'm not sure if those parts are LR308 specific or proprietary to Aero but in the world of large frame ARs, I think the only more LR308 compatible build would be an all DPMS LR308. The one proprietary feature of the M5E1 that I go for is the enhanced upper/handguard combo. It utilizes an inverted barrel nut and the handguard bolts to the extended snout of the upper receiver instead of the barrel nut. This is a feature that a few other manufacturers do but Aero does it cheap. You have to go to PSA or no-name China parts to get an upper with a free float handguard for much less and that won't have the extended snout connection. The other thing I go for is the integrated trigger guard. It looks nice but mostly I don't have to mess around with roll pins or worry about cracking a trigger guard ear. Once you have the basic combination of lower, upper, handguard and partial LPK (around $300 total if you shop smart), pretty much anything else available for an LR308 compatible should drop in. I'm not sure if every AR type gas block will fit under the handguard but that's a compatibility issue every AR has to worry about and Aero's enhanced handguards do seem pretty roomy. To me, ease of assembly is a feature because assembling incompatible parts is never easy. This Aero base I like might sound like it is locking you in to one manufacturer but prices are reasonable and if you break or wear out the upper, lower or handguard, you've put it through hell and Aero as a company seems stable and manages to keep everything in stock pretty consistently so it seems like as safe a bet as any other manufacturer.

A while ago I bought a few very inexpensive M5E1 lowers to add on to another transfer and since then I've been bargain shopping. I got M5E1 enhanced uppers, Quantum M-lok handguards and partial LPKs to match. I prefer the "AR10" carbine buffer setup with the tube and spring from POF, their P308 7 position setup (bought on sale but quality seems on par with Armalite and Vltor). For BCGs, Toolcraft. A clamp-on adjustable gas system from Odinworks. Charging handle ambi from Mega (on clearance at JSE). A Strike Industries Viper Modular fixed stock. A drop-in match trigger, assorted barrels, ambi selectors and ambi magazine release. Everything is nice and everything fell together. The upper to lower fit is plenty tight without even touching the setscrew designed to tighten it up. The trigger guard is great because I don't have to mess with a trigger guard roll pin. I have to tune them at the range still which means I need to try my selection of AR buffers but everything looks great. It's a stark contrast from my first large frame AR build which seemed to fight me a little every step of the way (but eventually turned out as I had imagined). I researched a lot and avoided major issues but had to do more filing than I would like. With less research or if I hadn't been willing to take a file to brand new parts, my first would still be parts instead of a rifle. I know some people go for ultra-lite builds and some people want billet receivers but for the price and how easy it is to build, I'm not sure why Aero isn't at the top of everyone's list? I have heard some good and bad about Aero's Ballistic Advantage barrels and I've had good luck with Criterion so I like to go that way and I'm trying Wilson Combat barrels (bought at 25-50% off). I made this thread for two reasons, first to see if anyone has a good reason and second to tell people how easy an Aero M5E1 build can be. Large frame ARs don't have to be hard.