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RyanRalston12
03-21-13, 10:45
I'm shopping around and am thinking it may be easier to piece together a BCG. Would a nickel boron carrier and phosphate bolt work together? Both are mil spec but I wasn't sure if the materials mattered...


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plouffedaddy
03-21-13, 12:57
Joe Bobs has one in stock now for $179

http://www.joeboboutfitters.com/JoeBobOutfitters_Enhanced_Complete_BCG_p/jb-enhancedbcg.htm

9130 bolt but in stock....
RyanRalston12
03-21-13, 13:06
Joe Bobs has one in stock now for $179

http://www.joeboboutfitters.com/JoeBobOutfitters_Enhanced_Complete_BCG_p/jb-enhancedbcg.htm

9130 bolt but in stock....

Thanks. I actually just went ahead and ordered an American Spirit Arms BCG but may pick up some more later.
markm
03-21-13, 13:29
You can mix and match all that stuff, Jackson.

I've been piecing a lot of BCGs together. Milspec key, Chrome Carrier, Phosphate bolt.

I have a Colt bolt in a Failzero Carrier too.
mtdawg169
03-21-13, 16:42
What's the story on all of the 8620 and 9130 bolts that seem to be floating around lately?
Iraqgunz
03-21-13, 16:54
Because they can't get Carpenter 158 steel. Bolt carriers are made from 8620 so they are using that. I would also be skeptical about any HP/MPI claims as well.


What's the story on all of the 8620 and 9130 bolts that seem to be floating around lately?
markm
03-21-13, 18:06
Yep. Demand will bring out the bottom feeding scum bags.
jwperry
03-21-13, 18:09
Because they can't get Carpenter 158 steel. Bolt carriers are made from 8620 so they are using that. I would also be skeptical about any HP/MPI claims as well.

I'd be curious to know the lifespan on a HP tested 9130 bolt compared to the C158 HP tested bolts.
KingsideRook
03-22-13, 00:18
I'd be curious to know the lifespan on a HP tested 9130 bolt compared to the C158 HP tested bolts.

Unless the military has previous test results on bolts in 9130, we'll probably never know. They may be fine, they may not be, but the only thing we seem to have real data on is Carpenter 158 bolts. Until someone sits down with 10 M4s with 9130 and a huge stack of ammo, and starts doing controlled, double-blind durability tests against 10 guns with C158 bolts, it's just an unknown quantity.

This is the sort of thing that keeps me using reputable brands - the unknown materials may be fine, but they are still an unknown. The less variables for weirdness introduced into a work gun, the better...
AKDoug
03-22-13, 00:32
It's 9310 not 9130.
Iraqgunz
03-22-13, 02:23
The original bolts were made from 9310 IIRC and they switched to Carpenter 158 after bolts broke in the 50,000-60,000 round count range.


I'd be curious to know the lifespan on a HP tested 9130 bolt compared to the C158 HP tested bolts.
markm
03-22-13, 07:47
The original bolts were made from 9310 IIRC and they switched to Carpenter 158 after bolts broke in the 50,000-60,000 round count range.

50,000?

That's not TOO bad. I'm assuming rifle system.

I did a google search a few weeks back and it brought up an OLD thread on some Machinist forum where some bottom feeder was looking to find a sub for C158 to make bolts. :p

Seems C158 had been a tough find for a long time.
mtdawg169
03-22-13, 09:30
50,000?

That's not TOO bad. I'm assuming rifle system.

I did a google search a few weeks back and it brought up an OLD thread on some Machinist forum where some bottom feeder was looking to find a sub for C158 to make bolts. :p

Seems C158 had been a tough find for a long time.

Is there a current shortage of C158? Possibly pre dating the late 2012 panic inducing events?
RyanRalston12
03-22-13, 09:31
Here's the bcg I bought yesterday: http://www.americanspiritarms.com/upper-parts/ar-15-complete-bolt-carrier-assembly/

I thought about buying a Phase 5 Tactical bolt carrier and then piecing some parts together to finish the bcg build.
markm
03-22-13, 09:34
Is there a current shortage of C158? Possibly pre dating the late 2012 panic inducing events?

From what I've heard.. yes.

It's always been a limited supply raw material. That 4 year old thread I referred to indicated that this guy's shop machined Bolts for a customer who provided their own C158 3/4" round stock.
Heavy Metal
03-22-13, 09:53
The original bolts were made from 9310 IIRC and they switched to Carpenter 158 after bolts broke in the 50,000-60,000 round count range.

No, the original was 8310, changed in the early 60s, IIRC.

Bottom feeders are still using 8310 from what I heard.