Blown primer and pressure signs?

[raythemanroe]

My uncle had shown me his 6mm rem casing that had a blown primer and a ugly looking pressure marks all over it...Then he told me he pulled his other bullets and weighed them, 11g below min...So I asked how the hell that happened naturally, and he followed up with the scale must of been sticking...Is that even possible? Wouldn't that end up with over loading? IMR 4350 was the powder and 105g amax was the bullet..

 

[Gruffskin]

Re: Blown primer and pressure signs?

I have never been a fan of the cheap scales that are offered from some of the big names out there. Moved to a lab grade scale and found confidence in the weights.

Gruff

 

[dynamic research]

Re: Blown primer and pressure signs?

If the load is to light you can get false pressure signs, which mimick high pressure signs. Since the case dosent pressurize into the bolt face you will get the same effect. Check for these before you panic.

 

[former naval person]

Re: Blown primer and pressure signs?

11 grains below minimum with 4350, ooohhh shit!...there is a phenomenon know as deflagration to detonation. Google it. A too light load with a slow burning powder will detonate. Glad his head is still on his shoulders. If he wants slow loads...use a fast powder. I know he wanted to save money. However, eyeballs are expensive. The too light loads don't mimic high pressure loads...they deliver it. And at a high speed. Do some research.

 

[raythemanroe]

Re: Blown primer and pressure signs?

Ya, he was using a lyman plastic scale..I use RCBS scale and I believe it is actually made by some other big scale company..

 

[Kinsman]

Re: Blown primer and pressure signs?

If the 11 grain deficit is consistent, I would look at operator error, rather than a sticky scale. I have had sticky scales, and they would weigh erratic loads, usually on the high side.