I have a MSL of .308 blanks.
They all have primers.  

How can I safely remove them??

Pulling powder and primers from blanks?

Is that what you wanted to ask?

I assume the primers are crimped.

DO NOT DEPRIME

The consensus is not to deprime live primers as they can go off.

My story on this.....

About 5 years ago I was decapping some of the old Tallon pull down 30-06 brass.

They were chemically killed primers.

About 1 in 20 started going off on decapping.

They would shoot sparks up an were pretty loud.

Some would detonate as they fell into the primer catcher in the 1050.

About 20 minutes in trying to take it slow one sort of had a hang fire detonation in the 1/3 full primer cup setting them all off.

Damn things blew everywhere and my right arm looked like I stuck it in a bees best.

I would imagine good primers would be worse.

In the end, the primers in the crimped brass wouldn't seat well in new brass and I lost about 50% of them.

Not worth it in my experience.

I've never set off a live primer while decapping it, but I've never needed or tried to salvage a crimped in primer.  I've deformed spent primers while decapping just because they were so tightly crimped in. If your primers are crimped in, I probably would not bother. Even if it didn't go off, it would probably be deformed or the pellet would be damaged.

What kind of blanks? M82? I recall they don't have crimped primers.

OP:
When you say "MSL" of them..... I assume you mean free...
Like the others, I don't think its worth it....  
BUT:
To answer your questions:
- You'd have to open up the front of the case to both empty the powder and then get a decapper
in there to press the primer out.  
I can't think of a safe way of doing that. (WELL that doesn't involve approx 5 minutes per case.....)
The powder is not usable for regular loads........  not at all.  
I have deprimed crimped primers before but it was like 5 ......and I was extremely cautious about it.......

So I don't see the point to destroying all that just to maybe get some primers out of them..........  
(The powder would get thrown away, you could get some money selling the pieces of brass for scrap BUT, No.)

Sell or trade the blanks........ and get the primers you want.........