write this in the crates init field:
this addweaponcargo ["AK47",3];
To add PK replace the AK47 with PK
With Dragunov...... I think you got my point. (Btw the name is SVDDragunov)
The number "3" tells how many guns you want to add. If you need ammo, just write addmagazinecargo instead of addweaponcargo. Hope this helps