Simple test loading GMX and TSX bullets with same components using factory COL and recommended loads from each bullet mfg. External bullet dimensions are very similar but bearing surfaces differ (grooves) as does bearing material (composition).
TESTED 308 Winchester 150 monolithic Hornady GMX and Barnes TSX using Varget powder, Fed 210 primers, COL 2.740 (GMX) and 2.785 (TSX). Rifle Merkel KR-1 with 22 inch bbl.
Gr..GMX...TSX (fps @ 10 yards)
40..2444...----
41..2471...----
42..2547...----
43..2600...2588
44..2664...2652
45..2696*..2684
46..----...2771
47..----...2812
*Max load... All cautions about working up loads for individual rifles. No pressure signs My interest was related to comparative velocity. Max vel was not reached in either group, and my velocities were under expectation. Max powder was exceeded in Hornady by 0.1 grain. COL appears important to normalize the groups. Re precision, all fell roughly in a 3 inch circle at 130 yards. Thought you might be interested and I would appreciate any thoughts.
Last edited by sawbones66; 05/19/16.
