GRIFFITH shooter Greg Allen reckons the finger-numbing cold of New Zealand will be the biggest obstacle to overcome when he takes aim in a trans-Tasman competition this week.

Allen and fellow Griffith marksman Warren Brown will travel to Oamaru to represent Australia at the combination shoot, which incorporates a trophy shoot, the South Island championships and two-day New Zealand compact titles.

The duo shot alongside Hay-based national representatives Peter Jacka and Jan Jacka in Griffith on Saturday in scorching 37-degree temperatures.

While the heat made competition challenging, Allen said it was preferable to the conditions the Aussie team would encounter in New Zealand.

"The last few days over there it's been about 10 degrees," Allen said.

"I hate shooting in the cold.

"I'd much rather shoot in the heat.

"When you've got a worn-out body with arthritis, the cold doesn't really do you any good.

"Plus you're wearing more layers of clothing.

"It's more restrictive and you're not as free to move as you normally would."

Allen said the New Zealand sun also presented difficulties.

"It's always brighter in New Zealand, which can make the targets difficult to see," he said.

"But it's all good. It just takes some time to acclimatise.

"Your body clock can be a bit out of whack as well.

"But you just take it on the chin and get on with it."

Despite the challenges, Allen said it was a thrill to represent his country.

"The traveling can be a bit of a pain in the butt, but it's always a good experience to see new places and new people," he said.