pressure in barrel

[Bartek]

Can someone tell me, please, what high is the pressure inside the barrel in the moment of powder's explosion?
Another words: what pressure (number of atmospheres or bars) has to keep the iron or steel pipe, which is designed as a ML barrel in the future?

 

[Stumpkiller]

I believe most rifles using blackpowder run 8,000 to 9,000 pounds per square inch of pressure. The proof test will be quite a bit above that. I'd want double to be comfortable if I was experimenting with untried metals. Strength has to be balanced with brittleness.

I've never seen it expressed as atmospheres, 14.7 psi is "standard sea level" = 1atm, so 600 atmospheres +/-??? 3-3/4 miles below sea level. :winking:

Astounding that Trieste went almost exactly TWICE that deep in 1960. 16,000 psi pressure on the hull. WOW!! :shocked2:

 

[Zonie]

It largely depends on the size of the bore, the projectile, the type of blackpowder and the size of the charge.

Lymans "BLACK POWDER HANDBOOK AND LOADING MANUAL" gives the pressures for most of their loads and most of the values are in usable values like PSI rather than CUP which is used for smokeless powder.

For a .58 caliber shooting a roundball with 120 grains of Goex FFg the pressure measured by Lyman was 7,400 PSI.(503.401 BAR)
For the same caliber/load shooting a T/C 555 gr Maxi the pressure was 12,900 PSI (877.551 BAR)
For a .45 caliber shooting a roundball with 120 grains of GOEX FFg the pressure was 19,300 PSI.(1312.925 BAR)
For a .45 caliber shooting a 200 grain Buffalo Ball-et over 120 grains of Pyrodex RS the pressure was 29,800 PSI.(2027.210 BAR)

 

[Bartek]

Thank You both very much :hatsoff: