I'm not a competitive shooter other than informal stuff. I've built a LOT of barrels using the GM blanks. (Retired now) If care is taken with them, just like if they were a high end blank, they will shoot quite well. I've got tons of pictures from customers that are well below MOA with many below .5 MOA.
BUT, my advise is to use high end blanks for serious competition. GM MAY produce an exceptional shooter but chances are the high end blanks will be more consistent in there accuracy.
If money is tight, you may consider the GM's. But if it doesn't produce what you want, you're out that much money that could have been used towards a high end blank.
GM's are fantastic bargains for hunting barrels though!!!
I'll post a few pics from my customers.
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