Provisional Irish Republican Army arms importation

Provisional Irish Republican Army arms importation into the Republic of Ireland for use in Northern Ireland began in the early 1970s. With these weapons it conducted an armed campaign against the British state in Northern Ireland.

In the early stages of the Troubles, during the period 1969–1972, the Provisional IRA was poorly armed. They had access to weapons remaining from the IRA's failed Border Campaign between 1956 and 1962, but these weapons were outdated and unsuitable for a modern campaign.

After 1969, and the split with the Official IRA, the Provisional IRA gained control of a majority of the stockpiled weaponry still held from previous IRA campaigns. They found that the stockpiles consisted mostly of World War II small arms ranging from Lee–Enfield and M1 Garand and M1 carbine rifles, to MP40 and Thompson submachine guns (SMG), plus Bren light machine guns (LMG) and Webley revolvers. The Garands were used in IRA operations as late as the summer of 1976, when a British army patrol in South Armagh was fired on by one of these rifles loaded with armour-piercing ammunition.

To continue and escalate their armed campaign, the IRA needed to be better equipped, which meant securing modern small arms. In previous campaigns weapons had been secured before hostilities commenced via raids on British Army and even Irish Army weapons depots. In the 1969–1971 period this was no longer feasible. By 1972, the IRA had large quantities of modern small arms, particularly Armalite rifles, manufactured and purchased in the United States. The AR-18 rifle in particular was found to be very well suited to the Provisionals' purposes as its small size and folding stock meant that it was easy to conceal. Moreover, it was capable of rapid fire and fired a high velocity round which provided great "stopping power".

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