StarWolf

Welcome, 308 ARs DO tend to have a bit of nuance.

Put me in the LaRue MBT-2S trigger camp. Bang for the buck is high, especially during the holiday bulk sales. I think I have 7 or 8 of them and I've bought a couple for friends. I wound up with three SSA/Es. I got them on a super sale. I think I might have paid about a third of going rate at the time.

Knights makes a dual spline version I saw at Midway last evening, $100 and out of stock no backorder: https://www.midwayusa.com/product/1022862662?pid=437619

Another old thread with a few additional tool options: PRI sold a small delrin bench tool to support low profile gas blocks combined with a short roll pin holder punch to install the gas tube roll pin. Maybe a bit expensive but was recommended by my old mentor. https://www.precisionreflex.com/ar-15-and-308-tools/501-gas-block-fixture-with-roll-pin-starter.html Saint Michael's Armament produced a Gas Block Tool (GBT), GBT Widget, Step Widget and Hollow Widget tools that mount set screw gas blocks on one end and are held in a vise at the other to allow you to easily hold the gas block while installing the roll pin. The advantage to this one was it worked with just about any gas block. https://www.saintmichaelsarmament.com/ Forward Control Designs puts out an aluminum fixture a little more refined than the PRI one: https://www.forwardcontrolsdesign.com/GPT-Gas-tube-Pin-Tool_p_218.html There was an identical Modern Army version that was more or less identical to the FCD one except for the logo. I'm not sure if it is still out there. Both of the latter ones claimed some incompatibility with various manufacturers and styles of gas block including adjustables.

I know this is an old thread but I thought I'd mention a few additional tools for installing a bolt catch roll pin in an AR, whether it's a small or large frame. Real Avid makes a set of roll pin holder and roll pin punches that are both extra long and flattened on one side to make this task easier: https://www.realavid.com/product/bolt-catch-punch-set/ Before those were out there was a similar long set of smaller diameter punches that included the roll pin holder and roll pin punch produced by Xtreme Precision: https://ar15xtreme.com/store/product/ar-15-extra-long-3-32-bolt-catch-roll-pin-starter-finish-punch-set-sku-946/ There is also KAK Industry's 'Walt's tool' which is a small diameter extra long roll pin holder: https://www.kakindustry.com/walts-tool

I'm a tool hoarder. I've been using the Geissele Reaction Rods for years. Got the 308 one before any of the shops around here did and have used it on many builds. Loaned it to my friend who owned the shop to take apart a nasty build for a customer upgrade once upon a time and he swore it was the only reason he could disassemble the gun. I recently purchased the Midwest Upper Receiver Rods over the holidays when they were on sale. I didn't really need them but I LIKE Midwest, the price was finally cut down to almost reasonable and I'm a tool hoarder. A coworker of mine recently decided to dip his toe into the large frame AR world. I offered to help with his build since I've done a few and collected most of the tools. I don't however loan out my tools very often so I come with the tools. He's got a new baby and meeting up wasn't working out. He missed a few suggestions on my build parts list and he jumped the gun a little on the assembly, without the proper tools. So AFTER a false start or three and some damage to the rail on his upper, he asked me to torque the barrel nut and dimple the barrel for the gas block. He's using a Aero Precision receiver set. He got the barrel from me. It's a Axem 18" .308 Cromo with a .750" rifle gas journal. I've got another couple of them in the parts bin and passed another of them to another friend a few years ago. They LOOK like Ballistics Advantage product that might have been produced for Axem and were leftovers from a buy a shop guy did to get the one he wanted to build. The shop owner passed them to me when he moved out of state. When I slide the Reaction Rod down the receiver it didn't want to go into the extension. Maybe a 1/16th +/- but no more. Same deal with the MI URR, no sliding into the extension. So I go to pull out the other barrels out of the bin. The MI URR slides into the extension on an identical barrel, no sweat. Tiny bit of play once it bottoms out inside the extension. The GRR on the other hand goes in tight no more than about 1/8th of an inch. SO I pull out yet another .308 barrel I've had lying around for a while. This one is a Midway special (AR Stoner maybe, possibly rebranded Bear Creek?) The GRR goes in tight, near zero play but it bottoms out. The MI URR goes all the way down as well but has a tiny bit of rotational play when you try to twist it. I think I'm going to have to use the Plastix Revolution vise blocks to take this puppy apart so I can inspect it before I go forward. I'm thinking about using the MI tool to get it back together and torqued up to spec, assuming there's no damage under the barrel nut and that I can get it lined up in the receiver and on the tool before starting the nut. I'll probably dig out the other couple .308 barrels I've got in the parts bin to see if the pattern holds true. I've been thinking I might need to deburr the GRR a little the past two or three builds but it's always slid right in and all the way home before. The MI URR needs a little deburring on the vise side as the square end where it was cut off is darned sharp. The MI URR seems to be in the same ball park as the GRR for quality. I do like the fact that they squared off the shaft so it can still be used at 0 and 90 even with the sail.

I don't know of any reason why you shouldn't be able to swap out 'standard' bolts from one carrier to another. That's regardless of whether the carrier is side charging or rear charging. There may be some 'optimized' or proprietary bolt designs that don't swap without swapping the cam pin as well but those are pretty few and far between. If you have one of those you probably know it.

I'm a tool hoarder. I've been using the Geissele Reaction Rods for years. Got the 308 one before any of the shops around here did and have used it on many builds. Loaned it to my friend who owned the shop to take apart a nasty build for a customer upgrade once upon a time and he swore it was the only reason he could disassemble the gun. I recently purchased the Midwest Upper Receiver Rods over the holidays when they were on sale. I didn't really need them but I LIKE Midwest, the price was finally cut down to almost reasonable and I'm a tool hoarder. A coworker of mine recently decided to dip his toe into the large frame AR world. I offered to help with his build since I've done a few and collected most of the tools. I don't however loan out my tools very often so I come with the tools. He's got a new baby and meeting up wasn't working out. He missed a few suggestions on my build parts list and he jumped the gun a little on the assembly, without the proper tools. So AFTER a false start or three and some damage to the rail on his upper, he asked me to torque the barrel nut and dimple the barrel for the gas block. He's using a Aero Precision receiver set. He got the barrel from me. It's a Axem 18" .308 Cromo with a .750" rifle gas journal. I've got another couple of them in the parts bin and passed another of them to another friend a few years ago. They LOOK like Ballistics Advantage product that might have been produced for Axem and were leftovers from a buy a shop guy did to get the one he wanted to build. The shop owner passed them to me when he moved out of state. When I slide the Reaction Rod down the receiver it didn't want to go into the extension. Maybe a 1/16th +/- but no more. Same deal with the MI URR, no sliding into the extension. So I go to pull out the other barrels out of the bin. The MI URR slides into the extension on an identical barrel, no sweat. Tiny bit of play once it bottoms out inside the extension. The GRR on the other hand goes in tight no more than about 1/8th of an inch. SO I pull out yet another .308 barrel I've had lying around for a while. This one is a Midway special (AR Stoner maybe, possibly rebranded Bear Creek?) The GRR goes in tight, near zero play but it bottoms out. The MI URR goes all the way down as well but has a tiny bit of rotational play when you try to twist it. I think I'm going to have to use the Plastix Revolution vise blocks to take this puppy apart so I can inspect it before I go forward. I'm thinking about using the MI tool to get it back together and torqued up to spec, assuming there's no damage under the barrel nut and that I can get it lined up in the receiver and on the tool before starting the nut. I'll probably dig out the other couple .308 barrels I've got in the parts bin to see if the pattern holds true. I've been thinking I might need to deburr the GRR a little the past two or three builds but it's always slid right in and all the way home before. The MI URR needs a little deburring on the vise side as the square end where it was cut off is darned sharp. The MI URR seems to be in the same ball park as the GRR for quality. I do like the fact that they squared off the shaft so it can still be used at 0 and 90 even with the sail.

The barrel extensions are not the same size. The ends on the AR-15 sized one is different from the .308 one. At least that's the case for the MI URRs and the GRRs.

I haven't read all 30 pages that have gone before, yet but here's some of why I ended up getting into .308 ARs. I'm in Kalifornia, have been since just before the Kali-ban went into effect. I had no real reason to get an AR until they told me I couldn't get one next year and so I bought a receiver and a coworker ended up selling me a complete gun before the ban took effect. As I recall .308 ARs were mostly Armalite at the time and AR-10s couldn't be had for love nor money. Kludges started appearing. ARs with magazines that required the gun to be broken to load since they were milled without the bottom mag opening and set up like a bolt action with a blind mag. Eventually the first generation bullet button mods started showing up and a friend at the gunshop got me interested in assembling that AR-15 lower I bought a decade or more before. After that build, I started slowly picking up parts for a .308. Mind you I'd already picked up a M1A when they came out without the bayonet lug before the Kali-ban. Before I built the .308 AR I had a couple M1As, a CZ-550 and a Browning BLR in .308. Building a large frame AR that could use the same ammo stash made sense. That gun was a Aero Precision M5 receiver set that I picked up on a Black Friday sale with their lower parts kit for less than my dealer friend could get them normally. Got a Rainier select barrel also on sale. Added an Aero NiB M5 BCG. Magpul UBR, Heavy carbine buffer and spring from heavy buffers dot com, Midwest handguard/rail, Magpul BUS, VLTOR extended charging handle, Warne ultra high QD rings and a Leupold 3-9X Patrol. Later I swapped out the trigger. I think this one ended up with a LaRue MBT-2S. I had to mod it when the Kali gov changed the rules. One of my coworkers was getting almost the same exact parts, Juggernaut handguard, different mount, scope and muzzle device but otherwise the same. Both of them ran and I've been hooked on putting other ARs both large and small frame ever since.

Hello from the guy who joined and posted after you. Your build list doesn't look much different from some of mine. I usually use a Midwest Industries handguard. I like LaRue's MBT-2S triggers for the price. (they come with trigger/hammer pins unless you want the anti walk style) I like Warne QD rings, they can be a bit heavy but they are solid.

I've been dropping by from time to time over the past several years, finally decided to log on. I've been building large frame ARs for something like seven+ years. I had a friend and mentor who helped me out picking parts for my first one. I'm getting ready to put together a sixth personal build and have helped out a few friends with them as well as helping out at a shop for a few years. NOT an expert by any measure but reasonably lucky so far. I've assembled a couple Aero M5s, a couple Mega MATENs and I picked up components to put together a Palmetto PA-10 when they were selling kits cheap. The next build will be another Aero M5 initiated with a Faxon 20" barrel. All the parts are ready with the exception of an optic. The parts bin has a couple unbuilt Matrix large frame receiver sets sitting in them with most of the components needed to put them together. I've assembled more small frame ARs than I care to count. Tend to be a fan of lever actions, military surplus rifles (especially but not limited to U.S.) .22 LR addict and a fan of both pistols and revolvers.

A friend of mine gave me the Rifle and Optics toolkit w/All in one torque driver. It also came with their scope leveling tool. https://store.fixitsticks.com/collections/all-shooting-hunting/products/rifle-optics-toolkit-all-in-one-torque-driver I already had the Wheeler Gunsmith Screwdriver kit w/ the add ons and the Wheeler torque screwdriver. Not to mention a few other firearm optic related tools. I really like the all in one torque driver. The T handle isn't bad. The bits are decent but I honestly don't know if they are worth what Fix-it Sticks want for them in other kits or by the bit. As for the scope leveling tool. I'm not enamored with it. It requires some room between the scope and the rifle. It more or less requires flat spots on each. Bang for the buck is probably less than it should be but I think my friend got it essential thrown in back when the All in one torque driver was pretty new.