200 gr subsonic ammunition and the FAL

[me]

The only commercial 7.62x51 ammunition that
is subsonic seems to use 200 gr. bullets.

By and large I realize this won't be very
stable in a 1 in 12 twist rate FAL barrel.

However - am I likely to end up blowing the
muzzle brake of the barrel ?

If my calculations are right, then a 200 grain bullet at 320 m/s and about 200'000 rpm
should perform less than one revolution before it passes the muzzle brake.

Still - has anyone successfuly tried this ?

I'd hate to find out the hard way...

-- me

[Scott S]

Hey me,

Downrange accuracy might suffer, but you needn't worry about the bullet hitting the muzzle brake. It's physically impossible for the bullet to tumble that soon after leaving the rifled part of the barrel. Laws of physics (not a physics major so don't remember which one) state that objects in motion tend to remain in motion. The bullet has more than enough inertia at the point it leaves the muzzle to remain stable past the brake. Stability loss is gradual (relatively speaking). You might even have acceptable accuracy out to, say, 50 yards.

[sturmgrenadiere]

Yeah, I am somewhat puzzled about your concern with the muzzle break. The projectile is not going to yaw or destabalize for a while, if it even does to degree that becomes an issue. Besides, all calculations aside, you don't need to do any to figure it will not completely rotate before it passes the break, unless your break is over 12 inches long. Or a tube or something...

[This message has been edited by sturmgrenadiere (edited November 07, 2000).]

[JohnnyMac]

You should be OK with 200 gr in a 1:12 twist barrel (accuracy aside).

If you were going to use a suppressed rifle you could have problems with an unstable bullet striking the baffles within the suppresor.

JMc