PSB in 30/30

[Bear Tooth Billy]

I have an old 94 Win. with a worn barrel, I got an oversize mold and with 20gr. of 4895 plus PSB
I shot a 1 1/4'' 100 yd group yesterday. I'm new to loading with PSB, but it sure seems to be the
magic in this worn barrel. My question is, how much does the PSB affect pressure, and how should
I back off load data using it. I don't have a chronograph, and don't want to put too much pressure
with the 170 gr boolit in the old Win. I want to get a load to shoot out to 200 yds. Thanks

[TXGunNut]

PSB? Been a long day but I don't recognize that acronym.

[Bear Tooth Billy]

Poly shot buffer used as a filler

[Yodogsandman]

Poly shot buffer used as a filler

What type? Which manufacturer?

[TXGunNut]

I'm not a fan of fillers but have seen many threads about them, read enough to know I don't want to use them. Short answer is you do need to reduce your load but first research whether your powder is position sensitive, may not be necessary. I generally find a powder/load that fills at least 90% of the case, best loads seem to be 95% or better.

[w30wcf]

TXGunNut,
The reason that BTB is using PSB is that it acts as a flexible gas check, keeping the gas behind the bullet in his rifle's less than perfect bore. Without it, accuracy was pretty dismal. Here is a great example of how PSB can really improve accuracy....in this case with an undersized bullet in a somewhat rough barrel.

http://i116.photobucket.com/albums/o25/w30wcf/Leverguns/44-40PSB1.jpg

w30wcf

[w30wcf]

BTB,
There was a test run sometime ago on various fillers in .450 x 3 1/4" using a 300 gr bullet and 48 / 4198.

No filler - 1,851 / 15,900 (hang fires)
Puff-Lon -1,911 / 19,600 (like PSB)
C.O.W. -- 1,907 / 25,300

Black Powder 1,812 / 21,600

Based on the above - your load of 20 / 4895 + PSB is plenty safe in your .30-30.:D

w30wcf