Factory ammo flat primers

R

reno92

New member
Like the title says the factory ammo I have have run through my 22-250 has flattened primers. In reloading for it I have run into the same situation. I can only get up to 36 grains of H-380 in it before the primers start looking warm. Is there any other reason for primer flattening other than over pressure? I have about given up on varget, starting loads are over top end in my rifle. I have never seen one that is like it. I know it shoots great, so I am thinking Tight bore. I recently got a chronograph but haven't tested velocity on the factory ammo or my handloads as of yet. Any thought's
 
mic a fired case and check the headspace VS a non fired in-spec case. My money is on excessive headspace on that rifle.

An easy way to check is just neck size a fired case (not full length) and run the same powder charge that showed flattened primers before, shoot the neck sized round and see if the primers look the same or not. If they look good with only neck sizing, you have a headspace issue, If they look the same your problem lies elsewhere.
 
Could be soft primers. Since you have a chronograph maybe you need to get out soon to fire some test rounds.

I have 3 boxes of ammo that after firing I started checking and they all had flattened primers. Never happened with any other ammo though. Just that one batch in that one rifle.
 
I will have to check out the headspace issue. any idea how much length is too much? As for the primers I have run winchester primers and remington. The factory ammo is winchester.
 
Update using a hornady headspace guage I came up with the following: full length sized cases; 1.562. the fired casings are; 1.5625-1.563. I am really thinking that the chamber is plenty tight, wondering if I have a tight chamber neck. sometimes on the cam down it feels like there is resistence but figure if that is the case the primers should look like more pressure than the ones that don't. All cases were trimmed prior to loading and haven't been reloaded as of yet. Avg neck thickness is .014
 
measure the neck on an loaded round and a fired case and see what differance is. Should be a few thousands bigger on the fired case. Hope this helps.
Chris
 
Sorry about pics. I am not computer savy enough. I am using the same primers in my .308 load development and they are doing okay there. This is the first possible anomoly that I have encountered. I will check neck thickness, other than a tight bore, or 22-250's run hot, Iam thinking I need to ream the necks. I wish I had access to another rifle to compare it against.
 
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