Hi Thomo,
I worked with a VTR that had the short triangular barrel. At first the gun would not shoot a decent group. We had to cut the dickens out of stock to float the barrel.This gun was difficult to work a load with, but we found it preferred Varget powder and Nosler bullets. We worked a load for the Nosler Accubond which has now evolved into the BT's. The rifle I worked with likes its COAL so long you have to use it as a single fed rifle. With all this said the gun now shoots well with a combination of good hunting bullets.