From: bartb@hpfcla.fc.hp.com (Bart Bobbitt)
Subject: Re: Powder cleanliness
Organization: Hewlett-Packard Fort Collins Site

Bob Hale (btree!hale@UCSD.EDU) wrote:
: ....which powders burn
: the cleanest?

I'll rate the ones I've used from 1 (dirtiest) to 10 (cleanest):

: AA 2460        6
: H 335          6
: H 4895         5
: IMR 3031       6
: IMR 4320       7
: IMR 4831       6
: IMR 4895       6
: RL 19          7
: W 748          7

Some not listed tend to be:

: IMR 4064       9
: IMR 4350       9
: AA 2520        8
: RL 15          8

Data is based on .308 Win., .30-06 and 30 caliber magnums using max loads.

BB

From: bartb@hpfcla.fc.hp.com (Bart Bobbitt)
Subject: Re: Scott powder
Organization: Hewlett-Packard Fort Collins Site

I've also noticed that smoke equals dirty bores.  Several folks I've
talked with have tried Scott powders and found them just like the
AA powders; very bore fouling and accuracy doesn't last long with them.
You have to clean the barrel about every 25 rounds or so and the last
5 or so shots aren't as accurate as the first 15 or so.  I'm still
convinced that for bullets heavier than 160 grains in a .308 Win.,
IMR4064 is the best.  You can shoot a couple hundred rounds and accuracy
is the same for the last 20 shots as the first 20.  Lighter bullets, like
the 155-gr. Palma, seem to do better with IMR4895, but you have to clean
your barrel about every 40 or so shots.  IMR4895 tends to foul the bore
more than IMR4064.  You can use IMR4350 with 200-gr. or heavier bullets
and it'll do just fine; burns clean and has a tad better accuracy than
IMR4064 with these extra-heavy bullets.  The 600-yd. record (200-19X)
was fired with Rem. BR cases/primers, Sierra 200-gr. HPMKs and 47.5 grains
of IMR4350.

BB