Target Rifle's premier championships at Bisley, is still restricted to the use of RG issued ammunition. In contrast the majority of overseas championships are contested with hand-loaded ammunition.
This then poses a quandary for any GB teams competing abroad. What ammunition to use when the majority of the team's domestic shooting experience comes from the use of factory-loaded ammunition. In a team of 18 there may be only 3 or 4 who have the knowledge and experience of developing and loading ammunition. Whilst they may be able to manufacture enough for their own needs while away, it is not a practical proposition for them to load for the whole team. A quick calculation of the time required to make the requirement of about 12,000 needed for a team gives a figure of about 150 hours, or 4 working weeks. Difficult unless you happen to be clinically unhinged!
But, ever in search of an 'edge', the team was keen to look at alternatives. One of these was the Lapua Scenar bullet. This recent entrant to the .308 target discipline is a familiar 155 grains, but has a moderate VLD (very low drag) profile, which improves it's ballistic co-efficient to 0.508, compared to 0.450 for one of its main competitors. This results in a shorter flight time and consequently less deflection by the wind.
The only person with mixed feelings was Martin Brown. Content with his product bearing up to scrutiny, and being asked to load for the tour, he now faced the onerous task of making 12,000 rounds. Good job the winter nights in Scotland are long and dark!

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Why the 155gr?
Are they not allowed to use the better 175gr?
I know the Palma limt is 155gr , Is this so for TR in general!

Why not use the superior 185 scenar?
Maybe it has a bearing (pun intended) on TR chambers. The Imperial rules on chamber dimensions say something about 'length of the leed must be such that the RG 155 is not in contact with the rifling'

Of course it might just be thay they do not realise different bullet weights exist.

Is the 185gr still supersonic at 1000yds or is it in the unpredictable trans-sonic phase?

175gr stays supersonic at 1000yds so gives 'predictable' accuracy........

I know the 185gr needs a faster twist 'in some' rifles to work properly.

Incidently - shhhhh  - the you know whos use 185gr, you aint seen me right..........