I'd like to know if it is worth fixing a "preban" AR by adding the appropriate evil features is worth it or even feasable, or if a new barrel should be purchased.  

I know the front sight base would have to be replaced to have the bayonet lug.  That would be less important than the flash suppressor.  The particular example I have appears to be about 3/4" shorter than some other preban type rifles I've compared it to.  This appears to have started life as a barrel made to accommodate the suppressor, but had the threaded portion cut off and crowned prior to finishing while the others seem to have been made to 20" with no threads ever on them.  Is this observation correct?

It seems it would be easier and cheaper to get a new barrel with a suppressor already attached than to have one properly attached to the current barrel.  Is this correct?

Quoted: I'd like to know if it is worth fixing a "preban" AR by adding the appropriate evil features is worth it or even feasable, or if a new barrel should be purchased.   I know the front sight base would have to be replaced to have the bayonet lug.  That would be less important than the flash suppressor.  The particular example I have appears to be about 3/4" shorter than some other preban type rifles I've compared it to.  This appears to have started life as a barrel made to accommodate the suppressor, but had the threaded portion cut off and crowned prior to finishing while the others seem to have been made to 20" with no threads ever on them.  Is this observation correct? It seems it would be easier and cheaper to get a new barrel with a suppressor already attached than to have one properly attached to the current barrel.  Is this correct?

Of course it's 'easier' to just replace it with a new one. The question is.. how much do you want to spend? Much cheaper to have Adco remove the muzzle device and put on a proper flash hider.

You can send your barrel to ADCO and I believe they charge $65 to cut and thread your barrel - - plus six bucks or whatever for an A2 flash supressor.   Much, much cheaper than a new barrel.

If you really, really do care about the bayonet thing, then it does become a little more complicated - but if your barrel is slightly shorter than a standard 20", then the bayonet wouldn't fit that well anyway.

Fixing a pre-ban is not that difficult of a job.  When the ban ended I took my Bushmaster A2 carbine and replaced the A2 stock with an M4 type stock off the EE, did not care for a bayonet lug so I left the FSB alone.  I also took off the barrel and took it to a friend who is a machinist.  He had never worked on a gun before but I explained what I needed done and it took about half an hour to turn the last 5/8" barrel down to 0.498" and then thread it with a die while still in the lathe.  He did not even charge me labor.  My total costs involved were the new stock assembly, the A2 FS, and about $6 for the die for the threads.  ADCO and some others have done great work on lots of rifles here, but cost was a big issue to me, as was quality, which is why I went the way I did.  The hardest thing to do in the project was taking off the barrel.  If you have the tools and ability to do that you can keep your barrel and save lots of $$ for more ammo.

Sarge

I agree with DK; ADCO makes a heck of a job in installing "Evil" features at a good price; put an FSB with a Bayo lug, threading your barrel and installing a FH and if you want to get more creative, flute the barrel and pait the whole thing in a nice shade of black to match your receiver.

Shouldn't be that much expensive to just install the FSB and the FH; plus their turn-aroudn time is a few days, so is a good choice. You can check with other members and they'll agree that ADCO is tops in their field.

You should take a pic of your rifle for a "Before & After" shots. Just to show what good a job they did.