Pressure within moderators

[onehole]

Just out of pure interest does anyone know what pressures are generated within moderators?  I know it will vary from cal to cal but cant help noticing some mods are built quite lightly and some like a tank,,,,,anyone? ,O

[Ronin]

I think, the pressure at the muzzle equates to 20 - 30,000 psi depending on cartridge (I recall reading this from Vaughns Rifle Accuracy the Facts book)

 

So it would, seem that pressures within then mod would be similar, though I have no hard mathematical evidence to back up my hunch.

 

Perhaps a mathmatition or stress engineer amongst our group could add to the discussion....?

[miki]

Boyles law (?) as the volume increases the pressure decreases ... so it'll depend on the volume. I imagine that if you worked out the volume of the gas produced by the powder and the amount of force needed to push the bullet out the neck, up the barrel and the increase in volume, you'd end up with a horribly complicated sum. Powder deflagrates (what a great word) so I imagine that the pressure isn't constant either, which wont help. I'll go for/guess about a 1/60th of the breech pressure.

 

[Moorlander]

I guess this makes it difficult to proof them for more than one calibre  as pressure curves could be sharper on a smaller calibre than say a .308W which many mods seem to be proofed for .

[Chanonry]

Happened to look at this last night. According to Quickload my 308 load in a 20" barrel has a residual 8 kpsi while a 7 SAUM was about 12 kpsi in a 25".

Not quite sure how that relates to what the mod experiences...

[onehole]

Thanks for replies,,,,,guess its pretty high initially but reduces so quickly that even a lightly built mod can cope well enough..........O

[ChrisF]

 

 

I think it depends on calibre size/charge , and barrel length , the designer for 3D TI suppressors from ODL in NZ , said that the blast/pressure from a short barrel AR15 , say 10 inches was the same as a large magnum rifle in  338LM .

Me I want strong suppressors , that can easily cope/handle the calibre its used on .