VASCAR2 Wrote:SDW, I haven’t seen any post regarding the bolt used by PSA other than they are 6.5 Grendel with .136 bolt face. Bll Alexander chose to use the .136 bolt face to permit more room for the extractor. A typical 5.56/223 bolt has a .125 bolt face depth and the bolt length from face to tail is 2.80. Bill A lengthened the 6.5 Grendel bolt to 2.810 to make up for the .01 deeper bolt. By going to a 2.810 bolt length the 6.5 Grendel can use the same length firing pin as the 5.56/223 bolt (mil spec BCG).Hmm. Yeah. I can't speak on Odin Works bolts. Don't have one. Nor a Brownell's. And I don't even have a PSA 6.5G bolt. Maybe I left out the detail about buying a PSA BCG for for 5.56. And I yanked out the bolt (it's now a spare) and I put in this badboy, which I bought from Ballistic Advantage (BA) along with my barrel:
If someone has a PSA 6.5 Grendel BCG which came with their upper measure the length of the bolt. Hopefully PSA did their home work and are using a 2.810 length bolt. Over the years there were a couple of examples of tolerence stacking where a bolt and firing pin had light firing pin hits. There were also a couple of situations with pierced primers because of out of spec firing pins and or bolts. These were very rare situations but when Odin released their 6.5 Grendel it was discovered they were using 2.800 length bolt with milspec firing pins. These 2.80 length bolts with milspec length firing pins resulted in excessive firing pin protrusion and pierced primers.
It is unknown if Odin Works manufactures their own 6.5 Grendel bolts or purchased bolts from another manufacturer. Brownell’s released their 6.5 Grendel BCG at about the same time as Toolcraft and both use 2.80 length bolts. If I were to purchase or use a Brownell’s, Toolcraft or Odin 6.5 Grendel bolt I’d measure the bolt and firing pin. Without measuring the firing pin and bolt length you won’t know what you have because milspec length firing pins have been shipped with the 2.80 bolts.
When LaRue 6.5 Grendel was released one forum member measured his bolt at 2.80 but later another member measured a Larue bolt from an UU kit and the bolt was 2.810. Many times manufactures will make product changes without announcing the change. To be on the safe side I’ve measured all my 6.5 Grendel bolts, firing pins and bolt face depths and all mine were within spec.
https://ballisticadvantage.com/65g-bolt-nitride.html
I have not measured the bolt's length. But I may as well. I do remember thinking that the FP (the one that came with the PSA BCG) seemed to protrude slightly more out of the bolt (after the 6.5G bolt swap) than say, the FPs in my other BCGs from... Anderson, DD, Bravo Co. Especially after reading a couple of threads here on the subject. I was thinking I got the dreaded "long" Toolcraft FP. It did measure out to be a little longer than one of my 'standard' pins. So I ordered a pin from Bravo, and that's what I am using now in this BCG. FP measurements are below. I pulled these numbers out of a post of mine from an earlier thread on a similar subject.
BCM pin = 3.274"
PSA pin = 3.279"
Protrusion "looks normal" now LOL But I should measure my Bolt as well, for uh, good measure. And report it here, just so we can have a record of what Ballistic Advantage is selling.
Also, I did put together a dummy round from a new, sized Hornady case and a 129gr Hornady bullet. OAL was 2.250", give or take. Dropped the bolt on it and racked it back a few times. Nothing odd happened: bolt locked up fine, no stovepipes, hah, and extraction flung the round out with a nice twirling action at about 4-5 o'clock. Same as I'd expect if doing this with a 5.56 round. So I can assume now that there's nothing wonky with my extractor.