Bristol Junction from Bristol Temple Meads is operated by South Western Railway, and there are scheduled coach links to most major UK cities. The M4 motorway connects the city on an east-west axis from London to West Wales, and the M5 is a north–south west axis from Birmingham to Exeter. The M49 motorway is a shortcut between the M5 in the south and the M4 Severn Crossing in the west, and the M32 is a spur from the M4 to the city centre. The Portway connects the M5 to the city centre, and was the most expensive road in Britain when
M4 carbine Marine Corps Infantry Automatic Rifle testing, the Colt IAR displayed a MRBS of CLASS I/II Stoppages of 952 rounds, with a MRBEFF of Class III Stoppages of 60,000 rounds. An array of firearms accessory makers have offered gas piston conversion kits for the M4. The claimed benefits include less needed lubrication for the bolt carrier group to run reliably and reduced fouling. The argument against it is increased weight and reduced accuracy. The Enhanced M4 uses an articulating link piston operating system. Complicating the Army search for higher reliability in the M4 is a number of observations of M4 gas