Failure to lock

[Redomen]

I was deer hunting with my 18” Faxon build and noticed when I charged the first round my bolt would not fully lock into battery. When i went to eject it I had to slam the butt against the ground to get the cartridge to eject. I found two marks on the rim of the case. It made me think I have a tight chamber or short throat. It has worked fine until the weather changed. I swapped carrier groups with my 12” build and same thing. Then I tried the same cartridge in my 12” with the original 12” carrier. Still failed to lock. I found 3 rounds out of a ten round mag that would not lock up. The ammo is factory Hornady SST. There does seem to be slight marks on the bullet. I will post pics when I get off of work. With it happening on 3 of 10 rounds I’m leaning towards ammo issue. Can the Horde give me any advice to what issue I might be having?

[A5BLASTER]

Sounds like the brass is on the long sized from the factory.

If you tried 10 rounds from the same box of factory ammo and 3 did the same thing, that too me sounds like hornady didn't get those cases trimmed down to proper length.

Just what I think, I'm no expert for sure.

[Redomen]

Here are pics

[A5BLASTER]

First thing I would do is tear your bolt and carrier down and strip clean them and clean the chamber up very good as well.


Looks like you have smashed brass shavings on the face of the bolt lugs, I would be willing too bet your chamber is just slap full of trash and carbon and that might be causing the issue.

I would clean everything really really well and then retry some rounds and see what if it does it again.

I have ran my rifles dirty before but I have never seen smashed brass shavings on the face of my bolt lugs before.

[bj139]

You could measure the case with a caliper to determine if it is too long. Compare to SAAMI values.
If headspace issue, you could try to place an empty 357 mag case over the bullet and measure from base to base.
Subtract length of 357 mag case to find headspace length. Compare to other cases which do chamber.

In your picture, there is also a HUGE dent in the case shoulder that may be the problem.

[LRRPF52]

Do factory Hornady rounds fall free from a clean chamber after being fully seated in the chamber by hand?

I don't let a barrel go into an upper unless factory and a set of my dummy cartridges drop free from a full seat in the chamber.

[Redomen]

I believe the dent was from when I ejected it and it hit the shell deflector. The other two rounds had no dent.

[FRB6.5]

Was the magazine a 4 round E-lander by chance?
If so I was chasing similar erratic issues with one until I discovered the magazine catch slot was cut too low on the body causing it to provide too much upward pressure on the BCG.

[Redomen]

It was a ten rounder and I swapped mags to no avail. It was an Elander though. I will double check that as well. Thanks.

[LRRPF52]

Looks more like a 5.56 extractor to me, not a 6.5 Grendel extractor. Could just be the photo, but the radius of the extractor groove and lip edge are looking a bit excessive to me.

I just compared with several Grendel bolts of mine, and I think your extractor lip corners are biting into the case rim excessively, causing binding as it tries to go into battery.

Are there wear marks on the outside of your extractor by any chance?

There are a lot of brass shavings all over your bolt as well.

Where did you get the bolt from?

[Texas]

Looks more like a 5.56 extractor to me, not a 6.5 Grendel extractor. Could just be the photo, but the radius of the extractor groove and lip edge are looking a bit excessive to me.

I just compared with several Grendel bolts of mine, and I think your extractor lip corners are biting into the case rim excessively, causing binding as it tries to go into battery.

Are there wear marks on the outside of your extractor by any chance?

There are a lot of brass shavings all over your bolt as well.

Where did you get the bolt from?

I agree with LRRPF52, that extractor is definitely shaving metal off the rim and looks like a 5.56 extractor. It is too far into the radius of the bolt face. You may try marking up the base of a case with a laundry marker and loading it into the chamber. Then look at the bottom of the cartridge for the extractor marks.

[bj139]

I just posted in another thread which seems to be the same problem.
Didn't Faxon have a problem with grit left in the chamber from the meloniting process?
This could make chambering difficult. There are already a few threads about this on this forum which can be found with a search.