Pressure signs

Reloading info for the 5.7x28mm

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ryan77724
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Pressure signs

Post by ryan77724 » 02 Jun 2020, 08:41

i'm having problems loading for my 5.7, i got my load data for true blue from loaddata.com for a 35gr bullet, and every single powder load is cratering the primers, and starting to flatten them a little. i'm not crimping yet, and i'm using 36gr varmint grenades set to an oal of 1.594", using cci small rifle primers. any suggestions would be greatly appreciated.

ryan77724
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Re: Pressure signs

Post by ryan77724 » 02 Jun 2020, 08:43

my powder charges start at 5.7 and go to 6.2gr increasing by .1gr for each different group

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Re: Pressure signs

Post by Buffman » 02 Jun 2020, 19:42

post a picture of them. What velocity are you getting?

ryan77724
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Re: Pressure signs

Post by ryan77724 » 04 Jun 2020, 07:33

i don't have any pictures right now, i'll post some in a couple weeks when i'm home. and i wasn't using my chrony when i shot the test loads, i'll try to get data next time i'm home

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panzermk2
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Re: Pressure signs

Post by panzermk2 » 19 Jun 2020, 09:55

For starters primer pressure signs mean absolutely NOTHING with the 5.7x28mm. They mean that also for standard caliber often also but the myths are strong.

The 5.7 is a high pressure delayed blowback round. They beat the hell out of the primers. This is why you have to use
small rifle primers for your loads.
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ryan77724
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Re: Pressure signs

Post by ryan77724 » 18 Aug 2020, 12:53

<a href="https://ibb.co/XXn2f5k"><img src="https://i.ibb.co/JnYBWpF/DCEE8-D09-93-F ... E7-AD2.jpg" alt="DCEE8-D09-93-F6-4-B4-F-AFD2-EA12-CE5-E7-AD2" border="0"></a>



See if I uploaded this pic correctly

ryan77724
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Re: Pressure signs

Post by ryan77724 » 18 Aug 2020, 12:55

Click the second https link and it’ll work, but that’s the pics of the cratered primers I’m getting. Is this anything to worry about?

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panzermk2
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Re: Pressure signs

Post by panzermk2 » 19 Aug 2020, 09:40

Pretty normal, the 5.7 is hell on primers. You can't use ordinary signs. You much better off looking inside the case.

You can see these gold rings once you know wht you are looking for.

These cases have been cut to make it easier to show what to look for.

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Image

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Jay Wolf
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ryan77724
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Re: Pressure signs

Post by ryan77724 » 20 Aug 2020, 11:17

So would you say those loads I loaded are safe to shoot then?

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panzermk2
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Re: Pressure signs

Post by panzermk2 » 21 Aug 2020, 08:08

Your at the limit of your primers.

What powders are you using? You listed the primers, small rifle which are correct. BUT what exact powders and charges are you using?
You do know if you browes this section there is verified good and also safe loading data correct?
Jay Wolf
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panzermk2
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Re: Pressure signs

Post by panzermk2 » 21 Aug 2020, 08:09

Also cut a case open and inspect it.
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ryan77724
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Re: Pressure signs

Post by ryan77724 » 24 Aug 2020, 14:15

panzermk2 wrote:
21 Aug 2020, 08:08
Your at the limit of your primers.

What powders are you using? You listed the primers, small rifle which are correct. BUT what exact powders and charges are you using?
You do know if you browes this section there is verified good and also safe loading data correct?
I’m using true blue. I’m not home right now but if I remember correctly I’m using 5.9gr

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Re: Pressure signs

Post by panzermk2 » 26 Aug 2020, 13:13

That can be at the max limit for 1x brass.
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panzermk2
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Re: Pressure signs

Post by panzermk2 » 26 Aug 2020, 13:13

That can be at the max limit for 1x brass.
Jay Wolf
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Be'ein Tachbulot Yipol Am Veteshua Berov Yoetz
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