Dread-pirate,
That's the one !
You can add quite a few things to the PTR later on if you
want.
HK made a great deal of mods/packages for the rifle that
will work perfectly on the PTR.
JLD does make longer barrels from time to time,but
currently they do not sell a rifle with one of these
barrels fitted .
I believe ,24inch is the longest barrel they normally produce,
and they don't constantly make them.Just from time to time.
There are other sources though.
Be aware that to change a barrel on this rifle is usually
going to require a smith ,and it isn't cheap.
When JLD made their last batch of 24s I think they were
$150 a piece.(because of the fluted barrel)
250 to 600 yards is about ideal HK range.
Past 500 the difference in bullet velocity due to the 18 unch
barrel has more of an effect.
The velocity difference isn't really that much between
the MBRs.Maybe ,200FPS between the PTR and an M1A .
I'd have to look it up.
I don't see the slightly slower bullet being effected by the wind
or dropping much more under 500 yards.
Past 600 yes ,and it would be very noticable at 800.
How often would you accurately shoot at a target at
that distance ?
(This is where the FAL guys jump in with the blasting clay
pidgeons at 600 yards 1st shot
)
At 600 yards I can barely recognize a human in dark colors
in most rural areas around here.
The PTR does have it's bad points,like any other rifle.
It kicks to,just get a rubber buttpad to help.
The FAL does have 2 big advantages to consider .
21 inch barrel versus the 18 inch PTR barrel,
FAL has last shot bolt open,HK doesn't.
I can say ,my PTR feels shorter than it really is in the field,
though heavy .(FAL is heavy to)
You might want to look up the FALfiles and HKweaponsystemsforum
for more info.
Good luck