04-21-2021, 11:56 AM
SDW Wrote:Hi all. While out in the desert shooting the other day, my rifle's extractor broke. I'm sure there's various reasons for it and I know it is not uncommon. First off, relevant info:
- Rifle has a 20" DMR profile barrel, made by Ballistic Advantage, rifle-length gas and rifle recoil system
- Bolt is also Ballistic Advantage, purchased with the barrel
- Total round count on the bolt/barrel is somewhere under 300
- Extractor broke while I was firing some work-up loads of 123 ELD bullets on 8208 XBR (broke at 3rd round of 27.9gr)
- No, there is no rubber donut around the extractor spring (spring is one of the longer "enhanced" types from BCM)
- Yes, I will be purchasing a SixFiveArms bolt as a replacement as soon as they're back in stock, hopefully this week
I'd like to buy a good quality (superior to BA's) replacement extractor, so as to put my BA bolt back in service, at least as a spare. Is this one of a decent type. Says it's made of MIL-S-5000 Steel, same stuff that SixFiveArms extractors are made from, so I assume it's 'the good stuff':
https://www.blackriflearms.com/-65-Grend...p_297.html
I know that JP also makes and "enhanced" extractor, but those cost nearly what a whole bolt costs from SFA/BFT. So I'm not leaning in that direction.
BTW, I was doing a little reading on this subject, various sites. Found a comment in this reddit thread discussing a broken Grendel bolt, in this case it was an Aero precision bolt/extractor. Aero has owned Ballistic Advantage for a few years now, so perhaps the parts come out of the same bin:
https://www.reddit.com/r/guns/comments/c...s/ewmw5ji/
No need to read the whole thing. Per one responder there, the gist is that:
I wonder if this is true. If so, then the break shouldn't be so surprising.
EDIT: BA says their Grendel extractors are (were) made from 4340 steel, which is the same as MIL-S-5000 steel, apparently:
https://www.ballisticadvantage.com/6-5-g...tride.html
So maybe never mind that.
Almost 28 grains of XBR with a 123? Surprised you didn't shear bolt lugs too. That load is too hot.
LR55