Dud primers or other problems?

SuperCub

SuperCub

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Bought a new T3 stainless in 270 earlier this summer. Been shooting it trying to get a load for this fall. Nothing working all that great but no problems with the rifle function wise. I like T3s.

One week ago last sat I tried another batch of loads. H4831SC, 130gr Sierra BT and some old CCI 250 magnum primers I bought about 10 yrs ago at a gunshow . Out of 18 handloads (brass full length resized) I got three duds that failed to fire. Primer strikes were very positive. No rifle problems whatsoever before this so I assumed it might be the old primers but I've had no troubles with them before either. So one week later I switch to three other primers to check on a good load I had the week before (WW WLR, WW WLRM and Fed 215s). All are newer primers and had not any troubles with them either. Shot 18 more handloads and got another dud with the WLR. Now I don't know if it's the rifle or the primers. Humidity is normal in the basement. Stripped the bolt last night and cleaned with light lube. Looked good but did it anyways.

Thoughts?
 
I tried shooting all of them more than once. This is the last one from sat. Been struck 4 times. The shadow makes it look deeper than actual.

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Is the bullet touching the lands? If so, this can keep the case shoulder off the chamber, so the case is not solidly supported when the primer gets hit.

This will soften the blow enough to cause a misfire.

Try the same test, with bullet seated 10 thou deeper.
 
Ganderite said:
Is the bullet touching the lands? If so, this can keep the case shoulder off the chamber, so the case is not solidly supported when the primer gets hit.

This will soften the blow enough to cause a misfire.

Try the same test, with bullet seated 10 thou deeper.
Click to expand...
Not sure I understand this. If the bullet is in the lands, would not the case head be as close as possible to the bolt face and aid in ignition?

Either way, the bullets are seated to the lands. I will try it .010" shorter and report back.

Thanks
 
I believe Ganderite is saying that jammed bullets might soften the impact sufficiently to prevent ignition. By backing off the bullets you make for a more abrupt impact on the primer.
 
cosmic said:
I believe Ganderite is saying that jammed bullets might soften the impact sufficiently to prevent ignition. By backing off the bullets you make for a more abrupt impact on the primer.
Click to expand...
Either way, I'm going to try it out. The CCI primers gave the best groups of the bunch so I want to use them.
 
Confirm headspace on your sized cases. Assuming your loads are not hot, the primers are showing indication of headspace related flattening

Take a sized case and put a piece of masking tape on the case head. Close the bolt and it should have alot of resistance. If not, add another layer and so forth.

If you get to 3 layers, you are way over sized for this chamber.

See if that helps narrow down problems.

If you can take the bolt apart and look for any burrs or dirt hanging up the firing pin. This is a new rifle so maybe, some assembly goop is still in there.

Jerry
 
SuperCub said:
Not sure I understand this. If the bullet is in the lands, would not the case head be as close as possible to the bolt face and aid in ignition?

Either way, the bullets are seated to the lands. I will try it .010" shorter and report back.

Thanks
Click to expand...

The brass will be forced up on the bullet when the firing pin hits the primer.
All the stars lining up for this to happen.
I'd buy new CCI primers that you like and try it again.
Never been fond of curb starts.
Prefer jump starts myself.

I'd be tempted to prime the brass and fire them off in the empty cases
just to see if there is/are any more failed primers.

Keep us posted on what you discover.
 
Mystic Precision said:
Confirm headspace on your sized cases. Assuming your loads are not hot, the primers are showing indication of headspace related flattening

Take a sized case and put a piece of masking tape on the case head. Close the bolt and it should have alot of resistance. If not, add another layer and so forth.

If you get to 3 layers, you are way over sized for this chamber.

See if that helps narrow down problems.

If you can take the bolt apart and look for any burrs or dirt hanging up the firing pin. This is a new rifle so maybe, some assembly goop is still in there.

Jerry
Click to expand...
Thanks Jerry ...... I did strip the bolt last night. Everything looked fine, but will check the headspace as you describe.

kamlooky said:
I'd buy new CCI primers that you like and try it again.
Click to expand...
I had the same thing happen with new WW primers.

kamlooky said:
I'd be tempted to prime the brass and fire them off in the empty cases
just to see if there is/are any more failed primers.
Click to expand...
I will do that, esp after neck sizing only.
 
Mystic Precision said:
Confirm headspace on your sized cases. Assuming your loads are not hot, the primers are showing indication of headspace related flattening
Click to expand...
Load was 59.5gr H4831SC with 130gr Sierra BT. 1/2gr below Hornady book max. A lot of the loads are showing flat primers as the ones in the pic.
 
I agree with jerry those cases have the shoulder pushed down ways to far if this is anything past the first loading on the cases. that alone could cause you issues but that is a solid pin hit if you ask me.

get the tools to measure how far you are pushing the shoulder back and set the fl die to 2 thou and lock it.

I have my own method to see if dud primers have any "fire". use your imagination and think safety first especially eyes. I have seen more than one that had absolutely zero fire. and one that had a little 1 inch pffff of flame and done.
 
Wonder if T3 has lighter springs.

Perhaps a different issue but on my T3 223 Hunter 10% of AE (black box) FTF whereas all fired with UMC ammo.
Granted 223 AE are AR ammo with hard primer.
 
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