I don't like them at all. However they do have a following. My post is really to assure you that even if the barrels are only 18" long they will still be deer legal with ANY factory loaded 243 cartridge in 100 grain or (where legal) sensible lighter weights.
This barrel length vs velocity vs legal velocity requirement I asked about some years ago when moderators were coming in. Apparent even before that tests were done on 308 and etcetara down to 16" and still legal.
Now in original 6.5mm x 54MS they won't be velocity legal with factory 160 grain bullets which struggled even to be velocity legal in standard barrel length Mannlicher rifles. I am told that there can be "issues" with maintaining zero over a fast fired string of shots.
6.5X54 160gr does not meet legal requirements[Scotland] both MV and ME below legal requirements.
Legal requirements Scotland
All species deer bullet 100gr min. MV 2450 fps ME1750 fp.
Roe deer 50 gr MV 2450 fps ME1000 fp
Yes we know about that bit of stupidity. It was quite enough to African Elephant but no capable of killing deer
Just use a 140 or 120 grain bullet. Norma, RWS and Kynoch used to load such weights.
I believe the velocity was also carefully chosen to penalise the 303 British as well.
30-06 200gr and 220gr factoy loadings will - 30-06 Springfield Ammunition let alone hand loads at 270 pressureStupid it may be, and I tend to agree but better than it was prior to 1986 when we had no restriction on what they were shot with, I remember in my youth when it was common practise for deer to be shot with shotguns and .22lr
both of which can do the job but I certainly would not recommend them.
The 215 gr 303 does not make the required MV, in fact not many bullet weights over 200gr will, apart from the magnum calibres.