Smitters it’s always been my understanding Model 1 Sales used 6.5 Grendel .136 bolt face with their 6.5 Sporter barrels. It’s entirely possible the original buyer was using the wrong bolt. A rifle barrel that was chambered to use a .136 bolt would probably function with a .125 bolt but would have excessive headspace. Looking at Model 1 Sales web site they list a BCG for there 6.5 Sporter. Model 1 Sales also list 7.62X39 BCG. I think if I were you I’d call Modell 1 Sales to see if they have ever chambered their 6.5 Sporter to use a .125 bolt. It would be good to know if M1S has used both bolts like Black Hole Weaponry who coined the Type I designation for .125 X39 bolts and Type II for .136 6.5 Grendel bolts.
If the barrel was chambered to use a .136 bolt I’d probably buy a Group buy 6.5 Grendel bolt from the forum. It would be a good idea to measure your supplied 7.62X39 bolt to see if the length is 2.81 and uses a milspec firing pin. Some 7.62X39 firing pins are enhanced with a longer tip to ignite hard military primers on steel cased 7.62X39.
Take a look at this thread there are pictures with the milspec AR-15/M-16 firing pin and 2.81” bolts.
http://www.65grendel.com/forum/showthrea...rier/page2
If the barrel was chambered to use a .136 bolt I’d probably buy a Group buy 6.5 Grendel bolt from the forum. It would be a good idea to measure your supplied 7.62X39 bolt to see if the length is 2.81 and uses a milspec firing pin. Some 7.62X39 firing pins are enhanced with a longer tip to ignite hard military primers on steel cased 7.62X39.
Take a look at this thread there are pictures with the milspec AR-15/M-16 firing pin and 2.81” bolts.
http://www.65grendel.com/forum/showthrea...rier/page2