Hornady factory 123gr SST - I think I have some pierced primers here.

[Bravo Vector Tango]

I shot 40 rds of factory 123Greset SSTs over the last couple days, having just solved an extraction issue, I didn't notice until pulling them from the tumbler that all 40 have very deep primer strikes with cratering. And at least 4 or 5 seem to have blown a primer.





I've had no issues with my reloads or factory 123gr AMAX.

in all my guns I've honestly seen such severe strikes and I've never had a blown primer, a bit unnerving.



I don't think my firing pin channel got flame cut, can't move it off axis.

What do You guys think? Thanks.

[Slappy]

Looks like it is rounded to me and sticks out further than normal. BANG BANG!!

[Bravo Vector Tango]

Grendel pin on the left. It does look damaged.

[JASmith]

The very flat primers coupled with marks on the bases suggest high pressures.

Have you tried extracting an unfired round after allowing it to chamber abd the bolt to go into battery?

What marks do you see in the region within about .25" from the case mouth?

[Bravo Vector Tango]

The very flat primers coupled with marks on the bases suggest high pressures.

Have you tried extracting an unfired round after allowing it to chamber abd the bolt to go into battery?

What marks do you see in the region within about .25" from the case mouth?

Now that you mention it, i did extract a live, unfire round while in the field, and noticed the bullet had a small ring around it just after the mouth of the case, and after the canalure, it went all he way around.

i don't have any more SSTs atm to replicate. jamming into the throat or lands?that would explain the primers i suppose, does factory ammo doing this in an AA barrel signify a problem somewhere?

My question is why would this happen with factory SST but not factory AMAX, or my handloads using 123gr amax (which were loaded to 2.255 COAL)

I replaced the firing pin, and will watch pressure signs with extreme dilligence in the near future.

[JASmith]

Try looking at a few more exracted rounds.

Light marks are OK. Heavy engraving may indicate a need for more detailed scrutiny.

[Bravo Vector Tango]

Try looking at a few more exracted rounds.

Light marks are OK. Heavy engraving may indicate a need for more detailed scrutiny.

Will do, from what I remember about that marked bullet from the field, the mark was very light.

I just measured protrusion of the firing pin, and both measured. 040

I also shot hornady an email, to see what they have to say.

[Bravo Vector Tango]

According to my research, that is too much protrusion.

I will be taking some measurements of the bolt itself next.

[Bravo Vector Tango]

According to my research, that is too much protrusion.

I will be taking some measurements of the bolt itself next.

Underground Tactical asked me to send the bolt in for evaluation, which I will likely do.
I do want to try a few handloads, and a couple factory AMAX, to see if the issue just "emerged" with the Factory 123gr SST's, or if it is for some reason, specific to those rounds.

[JASmith]

Will do, from what I remember about that marked bullet from the field, the mark was very light....

That's good news. Bill Alexander tells us that a "light kiss" is acceptable.

That also means that the bullet is as well-centered in the throat as it can be.

Excellent accuracy potential!

[m796rider]

10% off 6.5G bolts at alexanderarms.com... Just sayin'.

[Bravo Vector Tango]

10% off 6.5G bolts at alexanderarms.com... Just sayin'.

No kidding right? already leaning that way.

[37L1]

Underground Tactical asked me to send the bolt in for evaluation, which I will likely do.
I do want to try a few handloads, and a couple factory AMAX, to see if the issue just "emerged" with the Factory 123gr SST's, or if it is for some reason, specific to those rounds.

Here's what I think is going on.

The AMax and the SST have different ogives. While you may have no issue with the AMax loaded to mag (or SAAMI) length due to its long and narrow profile, the same cannot be said of the SST. Perhaps the factory load COAL is too long for your chamber and is seating them too deep when chambered causing a pressure issue leading to the pierced primers?

If you hand load and have a press, try seating the SST factory loads a little shorter (.020) and see if this issue goes away. Also if you have the Hornady/Stony Point tool you could check your chamber tolerance for specific bullets and load accordingly. I have found issues with an AR Stoner (Satern) barrel that fit this scenario. With my Lilja I have to load the SST shorter than Hornady factory SST while the AMax is fine at factory length.

Good luck, hope you get it figured out.

[Bravo Vector Tango]

Here's what I think is going on.

The AMax and the SST have different ogives. While you may have no issue with the AMax loaded to mag (or SAAMI) length due to its long and narrow profile, the same cannot be said of the SST. Perhaps the factory load COAL is too long for your chamber and is seating them too deep when chambered causing a pressure issue leading to the pierced primers?

If you hand load and have a press, try seating the SST factory loads a little shorter (.020) and see if this issue goes away. Also if you have the Hornady/Stony Point tool you could check your chamber tolerance for specific bullets and load accordingly. I have found issues with an AR Stoner (Satern) barrel that fit this scenario. With my Lilja I have to load the SST shorter than Hornady factory SST while the AMax is fine at factory length.

Good luck, hope you get it figured out.

Hey thanks for your input, I actually thought about seating the SSTs in the factory ammo a bit deeper, but I was hesitant as from all my reading hornady's powder charge is already stout, I would hate to make it worse pressure wise. I am relatively new to reloading and have never attempted something like that, but it almost immediately popped into my head, when discussing the bullet contacting the lands earlier in the thread.

I have Hornady new dimension dies with a micrometer seating head, so i should be able to adjust .005 at a time, and see if i can achieve no land contact within .020 of adjustment. What could go wrong right? 8D

I must admit to making a really poor assumption here - that the Factory SST was g2g in my barrel just because the Factory AMAX offering was. - A mistake I won't make twice.

[WIshooter]

I just got my first 6.5 Grendel together and shot 5 different kinds of 6.5 ammo through it. One of them being Hornady 123 SST. I also got a pierced primer, and several cratered primers and some ejector marks using this ammo. I am using AA barrel and bolt, so that should be good to go.
I Google searched problems with this ammo, and my gut is telling me this latest batch of Hornady 123 SSTs is TOO HOT. I wouldn't be surprised if they recall this ammo.

FWIW Hornady 123 AMAX shot great with no issues.