Okay I need some unbiased opinions about a Grendel bolt selection. If one had to chose between a Underground Tactical or Maxim Firearms type 2 bolt which would you select? Personal knowledge and/or experience appreciated.

Thanks.

Link?

I got one through tactical ammunition several years ago.  Probably had a thousand rounds with no problems.

I have purchased 2 type one bolts through Tactical Ammunition.  Did have ejector problems, one was too hard and cracked, another was too soft and wallowed out the pin hole.  These were made by an outside vendor.  I called TA and had new ones in hand the next day.  I only live about 80 miles away so shipping was fast.  Anyway I would definitely recommend them.  It is not about having problems but how they remedy the ones that arise.  I did order a few extra extractors but have yet to need them.  One has close to 1k and the other around 200 rounds through.

This is something I have been tracking for years now, with a lot of hands-on with various 6.5 Grendel bolts.

Here's how I would rate the ones I have experience with:

AA Hard Use Bolt
AA standard bolt
Precision Firearms (Maxim 9310 AQ bolt, with tuned tool steel extractor sourced and spec'd by PF)

A lot of the other ones out there have had issues because vendors don't know how to, or don't spec or QC them like they need to be.  This is true of any caliber-specific bolt, as well as 5.56 bolts.

A Grendel bolt is not simply an AR15 bolt opened up.  They are designed and made from scratch specifically to be Grendel bolts.  They're a different length (that still works with a standard firing pin), have a different bolt face depth, a different extractor, and if it is to be made correctly, it has to be heat treated properly, and QC'd.

AA does destructive testing on a certain percentage of their bolts to ensure proper heat treat and crystalline orientation of the alloy, surface hardness, and ductility.

I haven't broken a single 6.5 Grendel bolt and I've been shooting this cartridge since 2009 across several guns.  I have broken 5.56 bolts, and seen several 5.56 bolts broken over the years.   Online, I have seen bolts used in .264 LBC AR's break, and metallurgy has always been suspect on vendors not mentioned above.  There are others out there that have been fine, but I'm just listing the ones I have had first-hand experience with.

My recommendation is to look to AA and PF for Grendel bolts.  I haven't used JP bolts in Grendel, but I have heard praises for them by those that own them.  Keep in mind that extractors have to be made with certain types of tool steels, heat treated properly, with enough meat on the lip.  I like them tuned so they don't shred case rims.

I also personally prefer a chamfered or radiused ejector, and do all mine that way.  That is true for me on anything PPC-based in the AR15, as well as on bolts for the AR10.

Thanks to everyone who has replied. I appreciate you taking the time to share your knowledge and experiences.