My newest 6gt........Bartlein 7.5tw carbon rem varm. There's a major issue with it. Walks right about half to 0.6 mil as it warms up, then starts stacking shots. I've repeated this test two more additional times by alternating the first 10 rounds with each ammo sample, and same shit, half mil + walk right, but by round 10 or 12, it'll stack em, highest shot string I've went is 20 and it still under half moa.
I heard a few other have had to same problem with some 6mm Bartlein carbons, talked to one guy directly who had a bad barrel, Bart blames poor heat treat. Usually Bartleins are up to the task, but obviously some junk gets past the door too.
This photo is 3 different loads from a 22" 6gt on a bat action, 107smk at 2880, 108bt at 2860, and 115dtac at 2860. It does this every time I shoot it. Bartlein tells me they won't do anything till I have over 200 rounds and it's settled, blew my mind.
Load development was making me furious, I rarely ever shoot a carbon more than 6-8 rounds, before cooling. This is my 8th gt barrel, I know what they like........and this liked nothing.....until it got too hot to touch. I randomly out of anger one day just kept shooting, and by miracle it shot some tiny groups, blazing hot. It's repeated this tendency 6 times now with 19-20 shot groups.
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