Powder causing hang fires?

[bbyars]

Started using a powder I haven’t used before (TAC) in a 308 win. While shooting a ladder test I was experiencing a very small delay. I could hear the firing pin drop then actual shot. Fairly certain not a primer issue. I don’t wet tumble either. Just not for certain if it’s reloading related or the trigger tech is dying in the bolt gun.

Ladder was 41gr-43gr with a 155 vld. Has any one experienced this before?

 

[RegionRat]

TAC is considered a ball powder, which when speaking in generalities is subject to all the ignition issues with ball powders.

It is double base, meters well in progressives and powder measures, and very easy to work with in load development, but.... you will want to test for primer sensitivity and cold weather ignition issues.

Which 308 brass, large or small primer?
Which primer are you using?
Was the weather cool or cold?
Any issues with the rifle's ignition system?
The ammo headspace?
The primer seating depth?

 

[bbyars]

Alpha small
Cci450
Mid 80s*F
Impact action…none that I can see
..002 off
Flush…hand primer

 

[RegionRat]

Flush…hand primer

Primers should never be "flush".

They should be no less than touching the bottom of the primer pocket and then compressed.
The old terminology for that additional compression was "sensitized" but folks nowadays call that "crush" on the forums.
Try pushing those primers to where the anvils are forced in about 0.004" - 0.008" beyond touching.

Pocket depth tells us how deep the hole is. Primer overall height subtracted from pocket depth gives you a baseline value, then you go an additional 0.006" +/-0.002"

ETA: Example Let's suppose the primer pocket depth is 0.120" and the primers are 0.119"
0.120 - 0.119 = 0.001" to touch the bottom the primer is 0.001" below flush, then adding 0.006" crush your nominal should be roughly 0.007" below flush.

Also, if you have any large primer brass, that is worth a try.

Just for god measure, I would double check the ignition system. Look for gummed up lubricants, contamination, mechanical wear, worn springs, etc.

TAC is a good powder, but you do need to ignite it with more gusto than an extruded powder or you will get poor velocity stats and hang fires. The CCI 450 is probably not your issue, but they do want to have the anvil pushed in to work their best.

 

[bbyars]

Ran probably 15# of 8208 through this gun without issues until now. Only other primers I have is br 4 and some 250s for lrp but that seems like over kill for a 308.

Despite having ignition problems it shoots well

 

[Cascade Hemi]

Small primers, seated shallow, with light load.

 

[RegionRat]

Despite having ignition problems it shoots well

It will get worse in cooler weather if it is already showing in warm. While your NPA and follow-through are always important, this would make it like shooting blackpowder or airgun where the follow-through must be disciplined.

Those BR4 have a little different cup/anvil design, but you still want those to bottom out in the pocket as well.

TAC has a following, and for good reasons.

In for the range report for your investigation.

 

[bbyars]

Just curious now, and I know I’m being completely unconvinced…how are you measuring how much “crush” you are putting on a primer? I get using calipers to measure both the primer and pocket, but how are you measuring the primer once it’s in? Or are you just doing whatever the $600 primal seater is telling you that you are doing?

I found a 100x Win LRP I’ll give those a whirl and see if there’s any difference

 

[Cascade Hemi]

Primer seating depth gage with dial indicator from Accuracy One.

 

[R_A_W]

I just use the depth probe on my calipers a few times, then measure the total primer height and the primer cup height. I hand seat with a FA.

 

[RegionRat]

Just curious now, and I know I’m being completely unconvinced…how are you measuring how much “crush” you are putting on a primer? I get using calipers to measure both the primer and pocket, but how are you measuring the primer once it’s in? Or are you just doing whatever the $600 primal seater is telling you that you are doing?

I found a 100x Win LRP I’ll give those a whirl and see if there’s any difference

Primer "crush" isn't a direct measurement, it is a combination of tolerances and inspections.
As far as how to achieve good primer seating depth, it is done by two major steps.

The First.... is the math on your particular primer pocket depths and primers to determine the best seating depth.
The Second... is the inspection of the depth below the case head.

Neither of those steps has anything to do with a Primal Rights Seater.

Although that one works just fine, there are many primer seaters and it really doesn't matter which one you use as long as you use it to get intentional results by inspection of the installed depth.

If you have a typical caliper, you can just use the tailstock with a little dexterity and practice.

If you want to invest in your personal skills and toolset, I would recommend this one for it's simplicity and reliability.

https://bullettipping.com/products/precision-primer-gauge/

BTW, none of us can be sure from a forum post with respect to the cause of your hangfire observations.
Right now, the thing to do is to collect advice and form a plan for your next range tests and see if any of the advice helps.
You don't really have much risk/cost to investigate primer seating depth, or additional primer types.
If it were me, I would show up with a full slate of tests and then decide if I was going to add new tools/equipment etc.. YMMV
Good Luck and in for the range reports.