Adding buffer to a buckshot load and impact on pressure?

[faustus]

Ok, I am thinking about building a buckshot load with the CLBC wad ... but the recipe that I have are without buffer. Now, from my reading it seems that adding buffer to a recipe will increase pressure quite considerably and not just because of the increased payload but more because the payload cannot compress any more and help absorb the pressure spikes.

So my question is the following. Does anybody know by how much pressure would go up? Has anybody done any testing on this? Is there any consensus here?

I mean, are we talking about an increase in maybe 1000psi or 2000psi .... or will adding buffer lead to much higher increases ... lets say 5000psi .... ??

Here the recipe that I have ....


https://www.ballisticproducts.com/load16_06_17.htm

----------------------------------------------
Load#160519-8106 (EXPRESS BUCKSHOT)
HULL: CHEDDITE 12ga 2.75”
PRIMER: CH209
PROPELLANT: (ALLIANT) PROREACH 34.0 gr.
WAD: CLBC (Mica dust wad please.) Two long slits plus 18FW20 wad in base.
SHOT: Lead Buckshot #2 stacked in Rows of 3, 5 rows for a total of 15 pellets. (Approx. 425 grains.)
CRIMP: FOLD
RESULTS: PSI 10000 FPS 1565
----------------------------------------------

Thanks,
Faustus

[megasupermagnum]

From what I've seen, it's usually at least 2000 psi, if not more. The only load I had tested myself turned an ok 10,500 psi load, into a 16,000 psi dangerous one. That was tested by Tom Armbrust, a very good person to have test shells. The type of buffer effects it as well. I was using PSB buffer, which should raise pressures the highest, only topped by old-school flour. NEVER use flour, cream of wheat was better anyway.

[MOA]

That looks like a recipe from BPI. If you are wanting a load with a buffer so shot is protected more I suggest you look through more loads that they have that includes the buffer as part of the tested recipe.

[longbow]

I've never used buffered loads but have read up on them and gotten the same impression... best to use published loads or get some of your load recipes tested before trying them in your gun. Like many things shotgun it seems that results are a bit unpredictable so pressure tested recipes are the way to go.

Longbow

[faustus]

I think I found some answers here ....

http://www.shotgunworld.com/bbs/viewtopic.php?t=176827