Another drain on spolia is the very convenience of column shafts for the cutting of cannon balls for pierriers - that is, cannon designed to throw stone and marble shot, rather than iron shot, with often devastating results for the enemy, because the projectile shattered, thus acting somewhat like a shell. The pierrier was a common weapon in the mediaeval West, and accounts survive not only of the huge numbers of cannon balls manufactured by the French and English crowns, and their destructive power. In a sense canons-pierriers are the descendants of ballistae, which perhaps survived from Antiquity into the 9th century as torsion catapults (used by the Normans at the Siege of Paris in 885-6), and then apparently replaced by counterbalanced manganons as used by Charles the Bald in 873 at the Siege of Angers and then Paris. The Chevalier d’Arvieux, suggests they may have been used against Acre during the Crusades, for he saw in Acre and the environs in 1658 de gros boulets de pierre et de marbre, dont quelques-uns ont jusqu’à quatre pieds de diamètre, que les assiégeans jettoient dans la Ville et contre les murailles. This is likely, given William of Tyre's account of their destructive effect during the Crusader attack on Tyre: Excitebatur de collisis lapidibus et cemento dissoluto pulvis tam immensibus … quasi nubes interposita … in urbem cum impetu lapsi, aedificia magna cum habitatoribus in minuta redigebant fragmenta. Steinkrieg rather than Blitzkrieg?
The pierrier was, as a very large-bore cannon, a particular favourite of the Turks. It was conceivably invented by them or by the Venetians, perhaps used by the Knights at Bodrum, possibly used by the Turks in taking the Constantinople in 1453, and undoubtedly in the offensives against Rhodes. The courtyard of the Palace of the Grand Master still holds over 1,000 of them, and there are some very large ones in the city ditches. The greatest device at Rhodes was an “engine” called The Tribute, noted for the huge pieces of Marble it threw with an unspeakable violence but, by another account, sometimes without much effect. The great 40-ton Styrian Bombard at Constantinople in 1453 threw 700kg stones of 80cm diameter, but managed only three shots a day, and required over 100 men and 70 pair of oxen to manoeuvre.
Their use survived in Turkey well into the 19th century. (Whether the use of hollowed-out shafts for a whole battery of cannon, reported at Pergamum, caused damage, seems doubtful.) It is worth emphasising the enormous quantities of ammunition used by siege pieces: at Naumur in 1692, for example, the French had 262 pieces of artillery, and expended 40,359 cannon balls. These were not pierriers, and artillery in the Middle Ages would have been less numerous; but the drain on marble column shafts - so usefully produced in near-standard gradations of diameter - would have been enormous. Again, there is evidence that marble funerary colonnettes were also used to make such shot.
A French soldier examined the setup at the Dardanelles in 1726, and found that the pierriers there were seventeen feet long, of which eight feet are for the external length of the chamber, with an external diameter for the biggest of some two feet eight inches; thickness of metal: some eight inches, and throwing a ball of some 700 pounds in weight. Unnervingly, the Dardanelles batteries saluted friendly ships with shot, not just powder, and the nearer they go to the vessel, the greater the compliment : in a manoeuvre made yet more famous by Lord Nelson, such balls would cross the Dardanelles, hitting the water one-third or half the way across, and ricocheting the rest. Pierriers were also used on Turkish vessels, but were less feared: the Chevalier de Clairac, writing in 1726, notes such shot often emplanted themselves in the ship's planks, and the captains, especially Venetians, would prise them out and take them home for souvenirs. The Bosphorus and Dardanelles batteries were still using pierriers at the end of the 18th century, and they could certainly sink ships. They were still in use, and apparently still using re-cut antique columns, in 1838, with gunnery practice being a popular entertainment after mosque. There are still plenty to be seen at the Dardanelles, with the large ones outside the Jandarma opposite Canakkale naturally whitewashed, military-fashion, and many more decorating the various World War One cemeteries. No Western armies appear to have used them in the 19th century (although the French made use of Turkish stocks at Milianah: see below); but KilitBahir was still mounting eight pierriers (enormous bronze guns of ancient date, varying from 20 to 29 inches in diameter) in 1876. In 1853, the Turks are still carving cannon-balls very accurately in the quarries of Mount Ida but, pour économiser le travail, les tailleurs de pierre turcs ont profité des belles colonnes en granit qui se trouvent dans Alexander-Troas. But in spite of their reputation, advances in artillery and defence turned canons-pierriers into antiques. As a Royal Engineer reported in 1877 of the forts of Kilitbahir and Cannakale, These masonry towers, keeps and masonry batteries, must be classified with the stone shot guns that arm them - curious, as antiquities: useless, as fortifications or weapons.
 P.CONTAMINE, La guerre au Moyen Age, 4th edition, Paris 1994, pp. 338-9 for 15th century costs of pierrier balls; pp. 211-212 for siege of Castelnaudary in 1211, and destructive power; p. 212 for English production in 13th & 14th centuries;
 C. GAIER, Armes et combats dans l'univers médiéval, Brussels 1995, p. 262; he suggests that, by the 13th century, such devices were throwing 150 kilo stones over 150 metres;
 Chevalier D’ARVIEUX, Mémoires, Envoyé extraordinaire du Roy à la Porte, 6 vols, Paris 1735, I., p. 270;
 M.H. CHEHAB, Tyr à l'époque des Croisades, II: Histoire sociale, économique et religieux, 2 vols, Paris 1979, II.1, p. 255;
 Le General Baron BARDIN, Dictionnaire de l'Armée de Terre, ou recherches historiques sur l'art et les usages militaires des anciens et des modernes, 8 vols, Paris 1841, vol 7 s.v. PERRIER: Leur usage a laissé des traces dans la milice turque; de nos jours encore, des Pierriers qui défendent l'Héllespont, sont des canons lançant des boulets de pierre, et ayant un calibre d'un pied et demi à deux pieds;
 DE THEVENOT, Relation, cit., p. 216, within (apparently) the castle, on y voit quantité de pièces de colonnes;
 SHAT 30/MR1619 Extrait du Journal d'un officier russe, 1829: Notes sur un voyage de Constantinople. On that city's walls (pp. 30-31) reckons Mahomet shot pierriers at the wall:
 SHAT 38/1619 Considérations sur la Turquie et sur sa nouvelle organisation militaire of 21st June 1830, pp. 39-40 for Rhodes & Malta; p. 48 for the pieces guarding the Dardanelles;
 The Life of the renowned Pierre d’Aubusson, cit., pp. 179-180: these landed with such a force that they sometimes killed the Turkish sappers underground in their mines;
 KNOLLES, The generall Historie, cit., p. 584: with 12 bombards which “threw up stones of hugie waight into the ayre”, and 200 shot, only ten men were killed;
 GAIER Armes et combats, cit., p. 287;
 ARUNDELL, A visit to the Seven Churches, cit., p. 284: A curious expedient has been attempted, that of perforating some of the shafts of the columns, many of which are fixed in a row, and using them for cannon;
 GAIER, Armes et combats, cit., p. 290;
 C.N. KYRIACOPOULOS, Boulets en pierre du Pirée: colonettes funéraires remployées, in Bulletin de Correspondance Hellénique, CXVI (1992), pp. 217-27;
 SHAT 26/1616, M. LE CHEVALIER, Mémoire sur les Dardanelles; de Clairac, which he says in the preface he began writing on 2nd October 1726, pp. 126;
 Captain D. SUTHERLAND, A tour up the straits from Gibraltar to Constantinople, London 1790, p. 348;
 The Chevalier DE CLAIRAC, Mémoire sur les Dardanelles, SHAT MR1616,.pp. 103, 111ff, 115;
 SHAT MR1616, Nos 7-8, M. LAFITTE-CLAVE, Reconnaissance de Constantinople, 1784, includes a table of the artillery of the chateaux d'Europe et d'Asie, pp. 76ff.;
 DE TOURNEFORT, Relation, cit., II.444: the forts up the Bosphorus were still using pierriers, Erizzo capitaine Vénitien n’ayant pas voulu baisser les voiles, eut la malheur de voir son navire couler à fond par l’effet d’un boulet de pierre d’une grosseur prodigieuse;
 FELLOWS Journal, cit., p. 79;
 For example, the Abstract of Proceedings of the Director of Artillery for March 1876, with an extensive comparison of foreign artillery (PRO WO33/29, fol 120ff makes no mention of them);
 Sir G. WOLSELEY, Memorandum on the Anchorages in the Daradanelles…, Oct 20th 1876, on Kilitbahir, p.1; in PRO WO33/29, fol 417;
 SHAT MR1627, item 24, K. RASSAERTS, Forces armées de la Turquie, 10 March, 1853;
 R. HOME, Memorandum on the Dardanelles, 3 February 1877, in PRO WO33/29, fol 749; he states that the guns were founded in 1522, and that an immense supply of marble and granite shot exists to serve them (ibid., fol 759); cf. also PRO WO106/169 for a British Intelligence account by Capt E. R. Elles of The Peninsula of Gallipoli and the Dardanelles, 1880, with sketches and sections of the forts; he notes stone-shot cannon at Canakkale fort, and 15 bronze stone-shot guns - not eight as had earlier been counted - set up at Kum Kaleh;