Poped primers with min. load

Kazul

Kazul

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I'm reloading for a .303 Savage

My first reloads were IMR 4350 34.6Gr(min load) with a 150Gr jacketed RN.
Using the charts that came with the Lee die set.
They shot great but the primers backed out.

Can I change powder or primer to stop this??
Could it have been a dirty primer pocket??
Or is it indicating a problem with the rifle??
 
Backed out primers are usually a sign of low pressure not high.

I don't have any data for this old girl but I would think that IMR 4350 would be on the very slow end of suitable powders for this cartridge. I would think that IMR 3031 or similar would be a better choice.
 
Lyman 46th Edition lists

IMR3031 - 30.0 - 33.0

IMR4895 - 33.0 - 36.0

IMR4064 - 32.0 - 36.0

IMR4320 - 32.0 - 36.0

Not in any of my books is IMR4350 listed, including the IMR books.
 
I had this problem less than 2 weeks ago and had sevearl replies on my problem. I would start your load at the min and work up. watch for changes. if its no differant than maybe you have had a hot load in your brass and stretched your primer pockets? are you full lenght resizing? maybe you are " working" your brass a little excessive? have you tried a differant primer? These we all secnarios that were possible for me. I eventully bought new brass and discovered it had nothing to do with my loads it was simply bad brass. Hope this helps
Browndusti
 
I reloaded some .303 sav with 170 gr. Sierra FP. I tried H335 and IMR 3031. My primers backed out a bit also. I was using a model 99 as well. I contributed this to low pressure as others have stated.
 
'Boo said:
Backed out primers are usually a sign of low pressure not high.

I don't have any data for this old girl but I would think that IMR 4350 would be on the very slow end of suitable powders for this cartridge. I would think that IMR 3031 or similar would be a better choice.
Click to expand...

I will second this hypothesis, the firing pin drives the case forward and there is not enough pressure to drive the case back onto the bolt face, so the primer stays proud.
 
Head space?

Old lever guns are not the tightest and will work loose. If your'e relying on higher pressure to "push the primer back in" you might want to look into this. Fire a near max load and measure for stretching. The stretching will usually be just above the head and will grow the cartridge in length. If this is relevant to your situation, you might be able to cheat a little by backing off on the sizing die a bit to lengthen the shoulder a bit to take up the space in your chamber.


My 2 cents. WS
 
Put an .323 or .338 sizer button on your de-primer stem and run it into the case to expand the neck. Now, run it into your die with the 30 calber button back on but set the die to leave a short false shoulder that the rifle will just accept as a slight crush fit. When you fire the cartridge you will have a fire formed case that takes up any slack in your rifle. When you re-size it do not set the new shoulder neck juction back or you will be back where you started. You now have cases that headspace on the shoulder rather than the rim.
 
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