...This here, is the "Rubber Duck"
Well, I guess like a lot of walkie-talkies, the SWR stinks. Probably even worse, the lower in frequency, the harder it is to come up with the proper length of metal. After all, AM CBs transmit on VHF Low frequencies. However, at four watts, it may not matter much. The SWR could remain a little high at that low power respectively. The Hams do it occasionally, with a little help from an antenna tuner.
It's a little impractical for a hand-held radio. Just the same, I have used a CH 14 radio, with a 9v battery supply, compared to a 40 ch Maxon, 9 AA's, and can still talk across the lot to get my messages out.
Usually, these radios, if equipped with the right connectors, should be fitted with the longest antenna possible. The "Telescoping" antenna can be easily adjusted to a proper length for transmissions. I guess you could keep it as short as possible for close range communications ( like in the "Transformers" movie. ) Perhaps keeping it pulled out to it's fullest of length for maximum effectiveness, will do the job right. I guess it couldn't be too long.