Couplings

[chas4444]

Chas4444
New to model railways.
Can Bachman and Hornby couplings work together please?

[rogertra]

Replace them both with Kadees.

Best move you can make.

[SteamGene]

Roger is correct.  However, if you mean the Hornby 2-6-6-6, the answer is "no"for the as delivered coupler, which resembles a European coupler.  However, it has included both a knuckle coupler and a horn hook. 
In addition, the assumption is the Bachmann coupler you mention is the current coupler as, in the past, Bachmann used the horn hook.
Gene