Why is my 308 brass shrinking??
- Thread starter Brianma65
- Start date
Thanks,
My concern was ,can I still use this shorter brass.
And that’s been answered.
Thanks.
One more question though.
What would cause,3 of the primers ,to fall out of the pockets?
I primed 30 ,Sako brand brass and 3 of the primers just fell out.
The rest seem to be tight.
My concern was ,can I still use this shorter brass.
And that’s been answered.
Thanks.
One more question though.
What would cause,3 of the primers ,to fall out of the pockets?
I primed 30 ,Sako brand brass and 3 of the primers just fell out.
The rest seem to be tight.
And neck size if the brass was fired in your Sako before. No need to FL resize always, unless you're loading super hot.
The base of the case expanded making the primer pockets larger in diameter, in this instance you "may" be loading that brand of brass too hot.
Below the thicker the flash hole web and the harder the brass the longer the primer pockets will last.
And I have had factory loaded Federal cases with over sized primer pockets after the first firing.
And below while the illustration is greatly exaggerated it shows what excessive chamber pressure will do to the base of the case and your primer pockets.
Below is how I check any primers that felt loose when seating. I use a simple Lee depriming tool and if the primer moves with just finger pressure the case goes in the scrap brass bucket.
Yes, I had five loaded to max, and I did notice a heavy bolt lift.
Also these Sako brass are crimpe, and the crimp ring appears to be thinner in these 3 cases.
Also, I can prime these crimped cases ,with very little resistance.
I’m gonna toss all these Sako brass.
Also these Sako brass are crimpe, and the crimp ring appears to be thinner in these 3 cases.
Also, I can prime these crimped cases ,with very little resistance.
I’m gonna toss all these Sako brass.
This seems prudent. One might be ok if you can actually point to the reason the primer pocket is loose, but three is pretty much a red alarm warning. Not sure what you mean by a crimp ring. You mean the raised material around the edge that was supposed to hold the primer in when the brass was first loaded? It should have been removed before you primed these cases to reload them. It is possible that the primers are getting crushed/squeezed undersize when you are priming by this ring of material that should not be there and that is why they are loose in the pockets.
It looks like my IVI brass.It has a ring inside the pocket. Some of the rings are thicker.
None of my R-P or Winchester has this ring.
You can see from pics that the Sako brass has full ring in the pocket.
The R-P has no ring in the pocket.
Attachments
Dunno, good pics but I without 3D view I can't tell if there is a lip at the top of the pocket or not. You can always check them out by getting rid of any ring and forming a proper bevel with a primer pocket swager ( Dillon Super Swage 600 for example) or primer pocket reamer (Lyman primer pocket reamer for example). The swager is recommended if you plan of working with LOTS of crimped military sourced brass. I'd try and find a reamer for around $10-15, ream out the crimp ring on a couple of the loose ones, then try to prime with new primers and see if the primer goes in properly and stays.
Max is super hot like I said
I don't think it's a ring(material added) I think it's counterbore (material removed) AKA weakness/stretch.
Could well be that the pockets are enlarged from hot loads, but that ring shown in the pic of the Sako brass is definitely a full ring crimp as opposed to the three tab crimp which is common on a lot of the military brass. When the primer was seated a ring of material was pushed down from the brass completely around the top edge of the primer basically sealing the primer in position.
