You might want to check Remington's and Hasting's websites, I think they've redone the copper solid so it can be used in the Hastings barrel.

Mine is 1 of the old ones before cantilevers but it will lay 3 regular Brennekes touching at 100 yds. 5 Hornady H2Ks land inside a 3 inch circle at two hundred yds. Of 7 deer, between 100 and 200 yards, farthest any traveled was 30 yds.

Get the barrel.