The Vltor stock, with its battery-storage compartments, provides a wider and more comfortable cheekrest.

Trusty's tightened right to the perfect 12 o'clock position at just under 50 ft-lbs. That done, I slid the gas tube through the nut and receiver and then fished the other end into the front-sight post. Once it lined up, I tapped in the gas-tube pin, locking the gas tube in place. The GG&G free-float handguard then clamps over the barrel nut with six Torx screws. As final assembly of the upper, I put an A2 flash hider on the muzzle and a regular front-sight post--four position--into the front-sight housing.

While AR cognoscenti look down on lowers built by Essential, I have found this one to be dimensionally correct. The first thing I did when I received the upper was to check and make sure it fit. Uppers and lowers are supposed to be interchangeable, but with so many makers of both, you can easily find sets that don't mix and match. The EGW was a snug fit onto the Essential lower. That settled, I unscrewed the top bolt in the buttplate and pulled off the stock. With the buffer tube uncovered, I could see the rear takedown-pin detent spring sticking out of the lower. I pulled out the spring and detent plunger and set them aside. They are easy to lose in this step, and if you aren't careful you can be waiting for the next box from Brownells to finish your work.

I clamped the lower in a padded vise and grasped the buffer tube with both hands. Standard buffer tubes should not be wrung on with a wrench and absolutely should never be secured with a thread-locking compound. The tube proved resistant, so I carefully used a wrench to break it loose, then finished turning it by hand. Again, be careful with the buffer retainer and spring.

To attach the new buffer tube, install the retaining plate and nut, with the plate and its convex lump toward the tube opening and the nut behind it (closer to the buttplate) with its larger open ends toward the buttplate. Turn the buffer tube by hand until it almost covers the buffer retainer spring and plunger. Then press down the retainer, and give the tube another turn or two. You want the tube to keep the retainer in but without locking it down.

The GG&G fold-down rear sight, shown in both positions. When upright, it locks into place so it won't inadvertently be lowered.

Next, install the rear takedown plunger and spring, and slide the retaining plate down to compress the spring. Turn down the locking nut until it secures the retaining plate. Make sure everything is lined up before you tighten the locking nut. Some like to use an application of a threadlocking compound to keep the nut secure. I prefer to stake the nut.

Now slide the stock onto the tube. When the locking lever stops against the tube, pull down firmly on the stock lever to clear the back of the tube (not just levering it), and once the bolt clears the rear of the tube, press forward. Once it has started, you can let go of the lever, and the locking lever will snap into the first stop hole it encounters.

With the rails contiguous, you can mount the Holosight anywhere along the rail (left). If you don't like the light handle this close, switch the bottom rails on the handguard, and mount the light farther out (right).

The Vltor stock then simply requires you to select which combination of stock plates or battery compartments you want installed, and snap them in place. With either the storage tubes or the plain cheekpiece (or a combination) on the buttstock, tighten the clamping bolt through the bottom flange. To seal the storage compartments, you need to press firmly on the seal caps, then turn them to the inside. They won't go easily, but if you want a watertight seal, you have to work for it.

The only choice left is to use the top sling loop or an Uncle Mike's quick-detachable loop. I installed the Uncle Mike's, then found myself in a pickle. I hadn't planned on where to install the front loop. What to do without spending a lot of time hunting down sling-swivel mounts to go on the handguard? I dug in the parts drawer again and came out with the GG&G Sling 'n Light Combo. The SliC clamps in the front-sight tower and provides a sling location and a rail to mount a light should I need another rail.

All that was left in the lower was to install the new buffer and spring. As the tele stock buffer is shorter, I couldn't use the regular buffer and spring, so I pulled a shortie buffer and spring out of the parts drawer. With a little lube and a quick install, "Trusty II" was ready to go.

The only things left were to zero and test before using it in matches, classes or to keep handy in emergencies.