Alliteration is a prominent device in "Bayonet Charge." Throughout the poem, groups of shared sounds are used to help the poem convey a violent atmosphere, the loudness of those sounds reflecting the noise and chaos of the battlefield.
In addition to the above effect, there's also something very claustrophobic about the way that /r/, /s/, /h/, and /c/ sounds are used in the first three lines:
Suddenly he awoke and was running – raw
In raw-seamed hot khaki, his sweat heavy,
Stumbling across a field of clods towards a green hedge
These sounds work hard to bring the image to life. First of all, their claustrophobic closeness suggests the way that, though the soldier is surrounded by other soldiers, he is a resolutely solitary figure. This sense of claustrophobia is bolstered by consonance as well as the assonance of /aw/ and /eh/ sounds throughout. The /s/ sounds (sibilance, technically) suggest a sense of hissing, taunting awareness, while the /r/ relates to the friction pain of his uniform as he runs. The /h/ sounds are breathy, conveying exhaustion.
Later, the /b/ sounds in line 5 ("Bullets" and "belly") come across as aggressive and violent, helping the reader to imagine the bullets flying all over the place. The sharpness of "cold clockwork" has a similar effect, bringing the cruelty of the battlefield to life.
Another important moment of alliteration pops up in the last line. Here, the two /t/ sounds in "terror's touchy dynamite" (which are also consonant with the /t/ in the poem's last word) have a jumpy, nervy feel to them. This helps the poem end on an unresolved note of fear, the reader kept in the dark about what happens next (but aware that the probable result of the "Bayonet Charge" is the soldier's death).