Pierce was a strong swimmer and was awarded with a bronze medal and a parchment certificate by the Royal Humane Society for saving one persons life and attempting to rescue another. He received the medal when he was in Clongowes. While on a school tour to Tramore, Co. Waterford, one of his school friends got into difficulty while swimming. Pierce went to his assistance and brought him safely to the shore. About nine years later he swam the width of the river Suir near Cashel while it was in flood attempting to save a Mr. Tierney, who at the time was the first whip of the Tipperary Hounds.

In 1900, Pierce went to France and studied in Pau, France. It is believed that during his time in France he travelled to Denmark, where he inspected their farming methods. He attended an agricultural course in Dublin sometime in the early 1900's. When Pierce later ran the farm at Ballyowen his farming methods were widely admired. He also bred horses which he rode in competitions. He was nearly killed while riding in the point-to-point at Rosegreen in 1906, when one of his stirrups broke.

After Pierce left Clongowes he began to study the Irish language. When An Fear Mor arrived in Dualla in 1909, as a Gaelic League organiser Pierce seized the opportunity to learn the language and attended the classes set up by An Fear Mór. Pierce's interest in the Irish language meant that he went on holidays to the Gaeltacht. He had a special love for Connemara.  Pierce was actively involved in organising the Gaelic League in Tipperary. By 1908, there were eighteen Gaelic League branches in Co. Tipperary. The most active centre was in Knockavilla. Even though members of the Irish Republican Brotherhood (I.R.B.) were involved in the Gaelic League and had infiltrated it along with the various other nationalistic organisations like the Gaelic Athletic Association (G.A.A.) Pierce never became a member of the I.R.B.

After the formation of the Irish Volunteer Force (I.V.F.) in Dublin on November 25, 1913, the movement spread across the entire country. There were a number of Volunteer Corps set up in Tipperary in 1914. Cashel had a Volunteer Corp two days before the I.V.F. was formally inaugurated on November 25, 1913. On November 21, 1913, following a Fenian commemoration ceremony which was held in Cashel a group who had attended it decided to organise along the lines of the proposed Volunteers. A Volunteer Corp was established in Clonmel at the end of January 1914, by two friends of Pierce's, Seamus O'Neill (a lecturer at Rockwell College and later the Commandant of 2nd Battalion, Third Tipperary Brigade) and Frank Drohan. Both O'Neill and Drohan were members of the I.R.B. (Drohan was head-centre for Tipperary). A meeting was held in Cashel on March 23, 1914, to establish a Volunteer Corp. Pierce was on the platform and proposed the formation of a Volunteer Corp. The proposal was seconded and as a result four companies were formed. Officers were elected but only on a temporary basis. Shortly after this Pierce set about organising a Volunteer Corp in his native parish of Dualla. On April 13, 1914, he presided at a meeting in the village of Dualla in order to establish their own Volunteer Corp. That night sixty-eight men from Dualla enrolled and they began drilling the following night. The committee chosen was Larry Luby, Thomas Walsh, M. Dunphy, Richard Delaney, Pierce McCan, J.J. Connolly (Treasurer) and Sam Delaney (Honorary Secretary). The growth in the number of Volunteers around Cashel meant that a district council was set up. The district council included the following areas, Golden, Goold's Cross, New Inn, Rosegreen, Dualla, Boherlahan and Camas. At this time the Cashel Corp numbered about three hundred men. All through the Summer of 1914, the Volunteers continued to grow and training camps were set up. In the training camps military strategy was studied.

On July 29, 1914, Pierce took charge of the Tipperary Volunteers. When John Redmond urged the Volunteers to join the British Army and to fight in Flanders Pierce was totally against this. He was the only member of the Tipperary leadership of the Volunteers to refuse to give his support to Redmond's call. Doon Volunteer Corp were the only Corp in Tipperary whose members refused to join the British Army. This was probably because Sean Treacy and Dan Breen were members of it. Both Treacy and Breen were active members of the I.R.B (until Breen left it in late 1917).

Although greatly depleted the remaining Volunteers held their first convention in the Abbey Theatre, Dublin, on October 25, 1914. Pierce, Eamonn Ó'Duibhir and a few others attended from Tipperary. At