open at different times however pressure built up in the casing or wellbore from an open jet may impart pressure on the intact rupture pins of other jets forcing them backward into the tool to avoid this there are presented methods and systems for fixing the rupture pins in a jet the rupture pin may also or alternatively be held in the abrasive jetting insert by mechanical means such as a pin fastener and or a mating piece as shown in fig6 9 fig6 a b represent a cut away view of a jet showing assembly of a rupture pin with a pin fastener according to one embodiment of the disclosure an abrasive jetting insert 602 may have a jet into which a rupture pin 604 is inserted in this embodiment the rupture pin 604 includes a lower portion 606 and an upper portion 608 a pin fastener 612 may be attached to an end of the rupture pin 604 to hold the rupture pin 604 in the jet in the embodiment shown in fig6 a the pin fastener 612 is a nut that attaches to the base of lower portion 606 according to one embodiment the rupture pin 604 may be threaded on a lower portion 606 to allow the pin fastener 612 to screw onto the rupture pin 604 the pin fastener 612 may provide an opposing force that prevents the rupture pin 604 from falling out the back of the jet of the abrasive jetting insert 602 and into fluid flow the pin fastener 612 for example holds the rupture pin 604 in place during transport of the jet perforating tool containing the abrasive jetting insert 602 or during times of low fluid pressure in.