I'm tempted to snag one of Sharps extreme bcg made of S7 tool steel. But I'm worried about it eating up the barrel extension and/or bolt catches.

I don't remember the type of steel the extension is, but i want to think it's softer that S7 which makes me a little concerned.

I tried searching for better extensions, but only found BAT and various mfgs offering mil spec extensions.

What's the consensus?

Goal is a balls deep reliability setup. No weak links.

I run em in all my bcgs. Im not a super high round count guy (like 1k a year, honestly), but ive had no issues with em

So far my Sharps bolt has been great.  I don't see any increased wear to the barrel extension.  In fact, due to the NP3 treatment and the design of the bolt lugs I expect to see less wear over time.

I seem to remember a thread where a guy tested those bolts and it broke. If you want a bad ass bolt buy the LMT enhanced.

http://www.ar15.com/forums/t_3_118/658805_I_broke_the_unbreakable_Sharps_Reliabolt___TWO_BROKEN_NOW__Update_Pg__5.html

eta found.

I wouldn't buy the POS. LMT enhanced FTW.

To be fair: Sharps had a bad run and recalled them.  I haven't heard of another broken bolt in several years. 

I recently picked one up to try in my BumpSAW.  Guess I'll see how she holds up

Let us know the results. BumpSAW should really put it through its paces.

Yep, it will spend almost all it's time at 1,000 RPM.  I don't get out with it as often as I would like, but it still gets a decent amount of use.

Here is a clip from my last range trip with it, lot's of fun ringing the steal with it
https://youtu.be/E43IFdsH7eM

Got THIS from rainier in the email today or yesterday.

As i understand it, bolt AND carrier are S7 and is NOT the same as the Relia-bolt.

Correct me if I'm wrong.

I too remember the thread of the broken ones, but like another said, Sharps fixed it. Also just noticed after reading again, the extractor is not S7, which is kinda odd i guess.

The LMT is a first choice, but the Sharps bcg cost the same as just the bolt. Sharps has a pretty decent track record, so o thought it was worth looking into our possibly taking the plunge.

The Sharps Relia-bolt and Balanced Bolt Carrier are both made of S7 according to Sharps.  The Rainier Arms version looks to be the same, but with DLC instead of NP3 coating.

That's a sharps reliabolt. 

S-7 when heat treated and tempered for ultimate strength, will have a C-scale hardness of 54-57. This is not a problem for the extension. A nitrided surface is over 60 C- scale. Making a carrier out of S-7 is a waste. An 8620 carrier will out live you. The only problem with S-7 is it is not forgiving in heat treat. If it is not done precisely, you most likely will have a brittle bolt. You can not allow S-7 to cool below 120 degrees before tempering. I recommend double tempering. Craig

An 8620 bolt carrier from one of the decent houses is going to last a very very long time.
Bolts not so much.
There is or at least was a tech note on the Armalite website about the loading on the bolt lugs which explains a lot about why that may be.
Some of these super bolts may be better, but having a spare BCG on hand is probably the surefire way to keep your weapon running.

Same issues with 9310. It's cheaper to buy in bulk compared to C158.

I'm all for mil-spec, if there was anything truly better, it would've been fully adopted i assume. I was curious and thought about it. I think the only benefit for an S7 carrier would be the added weight maybe.

I'm deciding against it. Standard stuff is all I'll need. The critical heat treating concerns me, the probabilities are too high to fully trust it. I've personally never had a bolt break on me yet, just one extractor on my first build.

Thanks for the info.

The Sharps reliabolt extractor is S7 tool steel, as is the carrier (balanced carrier).

Sharps doesn't offer the NP3PLUS version anymore. They now do it with a DLC coating, Rainier is just getting the new ones. The extractor is not S7, it is a standard Mil-Spec one. Sharps did that cause it's a consumable item and can be purchased easily. Used a NP3+ BCG in a current build and a Reliabolt in an Aries carrier. The NP3+ is a dream to clean.

Double tap, sorry bout that.

Its a big problem in this industry is that "enhanced" products never release their testing data. I found many manufacturers unwilling to respond to inquiry regarding such data. Or, if they were willing to respond, they fell back on protecting their intellectual property. Understandable, but without the data how can we determine which products are truly enhanced?

I did my own digging and found data from a reliable source which introduced a method of cold work hardening the bolt which doubled the life of the bolt over a standard C128 bolt.

Whats interesting is that this process uses a standard milspec bolt and gives us *quantifiable* gains in bolt life without fancy bullshit coatings or major changes to the lug geometry.

I talk about it on my article:The Data Driven AR15

Low plasticity roller ball burnishing of the bolt is a low hanging fruit for a manufacturer to grab and their is data to back it up as a data driven step foreward in the enhancement of the AR15 bolt.

I hope someone can produce this product and integrate it into their product line.

That's why Bolts are C-158 and can go in excess of 15,000 rounds.

Barrett .50 bolts are S7 and last a very long time. We saw rifles with excess of 15,000 rds come in the shop that the bolt had no flaws after being magnafluxed.

I also like that Sharps has a lifetime warranty on their bolts.