ðɪ aʊtsˈaɪd ʌvðə bɹˈiːtʃ pˈoːɹʃən wʌz tˈɜːnd ˌɔn ɐ lˈeɪð sˌoʊ ðæt ɐnˈʌðɚ ɹˈɔːt ˈaɪɚn tˈuːb, kˈɔːld ðə bˈiː tˈuːb, kʊd biː slˈɪd ˌoʊvɚɹ ɪt tə stɹˈɛŋθən ɪt.
The outside of the breech portion was turned on a lathe so that another wrought iron tube, called the B tube, could be slid over it to strengthen it.