Jamming to Fireform

[mbeavers1]

I have about 100 pcs of 22 Dasher brass that the shoulders were pushed back 0.008-.010 that I would like to fireform. I was thinking it would be best to drop my charge a bit and jam some bullets then fire 1x.

Any idea how much I should drop? Normal is 34.5gr of h4350. Was thinking 33.5 should be fine and jam them 0.010-ish.

 

[nn8734]

How many firings on those 100 pieces?

If a lot, have you checked the case webs for signs of initial separation?

Dropping the charge one grain won’t make a difference insofar as safety is concerned unless you’re already at pressure with 34.5. Jamming the bullet won’t matter either (if anything that will increase pressure…

 

[mbeavers1]

1 firing and then hydro formed. Lapua brass. Not at pressure at 34.5. The jamming should increase pressure some so wanted to make sure i stayed way away. Just want to blow the shoulder back forward.

 

[Haney]

33.5 will be plenty safe , even at your usual 34.5 and w/ jam will likely not increase pressure enough to matter .