I have decided to swap my  16" shorty  barrel  for a 20" and had a few questions.

Will I need to get a different buffer assembly? I heard somwhere, can't remember were, that the buffer assembly is different on a 16" and 20" and I'll need to get a new one for the 20" or risk damage.

Will I also need to get a new bolt for the new barrel? Everything is Bushmaster. I was told from Bushmaster that I wouldn't as long as I don't have more than 2,000 rds through the gun. I only have about 500 but I thought i'd get a second opinion from you all.

Thanks for your advice.

You will not have to change the buffer unless you are changing the stock from a CAR to  an A2.

A new bolt is not needed either.  If yours was badly worn it could possibly cause excess head space if your new barrel/chamber were on the deep side of acceptable specs.  But as new as your bolt is I would not worry.  The prudent thing to do would be to order a head space gauge and check after you rebarrel.  However I have never bothered and I am still alive.

While many here aspouse this philosophy, I suspect it comes from the cheapness of people in general. An upper without the b/bc/ch is cheaper than one with'em.

Personally I'd never recommend the above to anyone, less'en it was someone I disliked alot....

Always, recheck the headspacing when you swap barrels or bolts.

Being safe, is better'n being sorry,
Mike  

When I was in basic training there were a lot of stupid people who probably mixed up bolts. I really think that this problem is rarely catastrophic.  

Sometimes I wonder how safe it is to put a barrel and bolt (that often come from different manufacturers) together period. The barrel wasn't headspaced to that particular bolt.  I just think that alone proves that the problem is more imagined that real.

[b]The headspace on most barrels people here buy is allready pre-set and the ext installed-- meaning for a perfect fit a properly sized bolt would be required IE many bolts with slightly different sizes to pick the right bolt for the barrel in mind. (something I don't really think exists on the market)[/b]



The military does a lot of unneccassary stuff :

Case in point the, allready carefully torqued, Castle nuts on my units new M4's are STAKED in place.  IE non-removeable.  That just seems a little overboaurd to me (what if a buffer tube gets bent? do they throw out the whole lower reciever?)

To be safe, I'd probably get a new bolt ($50).  You do not need the whole bolt carrier assembly.  Sell the old bolt with your 16" barrel; whoever buys it may want the old bolt.