My barrel is threaded, I have the A2 flash hider and the crush washer.  I need to put about a half a turn on the thing so it is properly indexed.  I have the barrel wrench, I have an upper receiver block, I have a vice.

How do I hold the barrel solidly enough to be able to crank down on the flash hider?  I need to put enough force on it to be able to cruch the washer.  Right now the holes in the flash hider are facing down.  So half a turn is what I need.  Washer is not crushed at all, I can't get enough pressure on it and I was afraid to put it in the receiver block, thought it would crank on something I didn't want to crank on.

What's the correct procedure?  Thanks

You will need a set of barrel vice bloks, this will hold the barrel in place tight enough so you can index the flash hider. If you do not have any vice blocks Brownells sell a nice pair of aluminum blocks with inserts so you do not scratch or marr the barrel surfice

Thank You
Js15

I've used an upper receiver block with good results and no harm to the upper or barrel.

If I use the upper receiver block, the barrel won't turn or torque down to much on the receiver when I start to crank on the FH?  This is my fear.

I've been told you should NOT use and  upper receiver block, as it can throw off the alignment ever so slightly, and put stress on the upper receiver.

So...I bit the bullet, spent the 15 bucks, so that I can be assured that I am doing it right, and won't have anything to worry about.

I WECSOG'd it by using two blocks of wood, padded with rags, and clamped the FSB in the vice. This shortens the length of leverage applied to the barrel.

Quoted: If I use the upper receiver block, the barrel won't turn or torque down to much on the receiver when I start to crank on the FH?  This is my fear.

No.  Read this thread to see why:
How to install flash hider?

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