I have an option of a 20" barrel or a 24" barrel on a PCR-1 Ultramatch (Broach cut 416 stainless steel heavy barrel, 20" OAL, 1x8" twist).  I intend to be shooting anywhere between 50-600 yards.  I'm not sure what bullet grain I will typically be using yet...something between 55gr and 80gr.

I am trying to decide whether I should keep the stock 20" barrel, or have a 24" barrel installed.  What would you guys suggest?  

1) would 24" be too long for a 55gr bullet? I know that longer barrel only increases velocity to a certain point and then it's gonna start having an inverse effect

2) how much weight do you think it would add, about 1 pound i am thinking?

3) how much more MOA accuracy do you think I could expect at 600 yards?

4) is the number of revolutions of the bullet within a barrel a useful number?  it would be 2.5 revs in a 20" and 3 revs in a 24".  if this is a useful number, what is the significance of it?

5) in your opinion, is it worth it?

thanks!

I'll take a shot at it.

1. The difference (if any) would be insignificant.

2. No idea.

3. None

4. No

5. No

Cheers!
Him

None of this shit has anything to do with learning to shoot or accuracy.

[url]ammo-oracle.com[/url]

ok, the ammo oracle is a great FAQ and I have read the whole thing, but it does not talk about this stuff...i dunno if its you but people keep replying to my questions by simply giving me this link over and over again even when it does not discuss relevant topics.

A longer barrel will give more velocity and more RPMs thus more stability.  However longer barrels whip more.  Becasue of this you will have more stability for long range ammo with the longer barrel and more velocity.  However shorter barrels of the same thickness are stiffer and more accurate/consistent all things being equal.

I would get the 20" as the 24" is a bit overkill and you could hamper accuracy ever so slightly while getting very little back in terms of velocity.  What is the maximum range you can shoot at your local range?  If you can shoot to 800-1000 yards, the longer barrel will help.  If not Stick to the 20"

Extra weight will be about half a pound or so.  Not a full pound unless its a REALLY thick barrel.

The number of revolutions inside the barrel means nothing.  Only the RPMs as the bullet leaves the barrel matter.  The slight increase in velocity will create higher RPMs in the 24".