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From: Norman Johnson <>
Newsgroups: rec.guns
Subject: Re: (Fwd) Re: 45/70 calculations WC860
Date: 21 Sep 1999 03:07:52 -0400

## ...The Speer #12 Reloading Manual shows loads to keep the 45/70 below
## 21,000 c.u.p. for a conservative derating [Trapdoor]. One such load is a
## compressed load of 53 gr of H4895 behind a 400 gr jacketed bullet....
#The use of slow burning powders in the .45-70 has been going on for
#decades.  H4831 was the first one I tried, and compressed loads were
#safly low pressure with bullets up to 450 grains.  Lighter bullets
#didn't shot well due to poor burning.  Fouling was bad with this
#powder, but accuracy was excellent with 350 grain bullets and up.
#WC860 will probably work, especially since Accurate shows compressed
#loads of AA8700 as giving .45-70 pressures of under 20,000 psi.  The
#comparisons with the same powders in the .45-70 and the .270 Weatherby
#could be dangerous, since the pressures are WAY different, and powders
#can burn differently at vastly different pressure levels.

I have been using a case full of the very slow powder like MR-8600,
MR-8700, H-870, MR-3100, H-4831 or the like, sometimes with an igniter
powder next to the primer, in my .45-70 loads (and several others) for 20
or so years.  A case full of H-870 with a couple of grains of 700X next
to the primer will give a load similar to that of the old black powder

As has been stated, unburned powder is left in the bore.  However, I have
yet to find that troublesome.  Blowing out the bore between shots does
not seem to change the already excellent accuracy.  If it really bothers
you, following the recommendation to use a couple of grains of Bullseye,
700X, or other fast pistol powder next to the primer as an igniter charge
will clean things up considerably.

MR-8700 is marketed by Accurate Arms and, in my testing, performs exactly as
does H-870. I also have some 8600 and 8700 powders that I purchased from a
Shotgun News advertiser for $2.00/lb. It is also evidently the same stuff. I
use lots of them for general shooting and for duplex loads.

If you want to take this very slow powder approach still further, you
might want to see my article "Duplex Loads" in "The Cast Bullet".  It
discusses my method for getting, more or less, standard factory
velocities in a number of cartridges when using these very slow, and
mostly very inexpensive, powders. The duplex load article is in The Cast
Bullet issue #123, Sept-Oct, 1996.

God Bless!


From: Norman Johnson <>
Newsgroups: rec.guns
Subject: Re: (Fwd) H110 gets cases dirty?
Date: 22 Apr 2000 11:27:55 -0400


#I have a 44 mag and 357 mag, that if I load with H110, will get black
#crud all over the outside of the cases.
#Why is the case not sealing?
#Is this normal?

The lack of obturation is due to powder charges that are not great enough for
the bullet being loaded.  Powders like W-W 296, H-110, and the like do not
usually do well with lighter bullets because sufficient pressure cannot be
generated even with a case full.  They do a great job with heavier bullets. 
Incidentally, if the load shoots well, the black residue will not hurt

I have just started to experiment with the very slow rifle powders in the
bigger pistol bores.  Some have read my articles about the use of very slow
powders and duplex rifle loads here and in The Fouling Shot.  As a result, I
have had a number of inquiries about use of these very slow surplus powders in
pistol applications.  I finally loaded some theoretically poor loads in my
Ruger Blackhawk .45 Colt.  Twenty five grains of MR-8700 under a 200 grain
.454" swaged lead bullet.  To my great surprise all twenty rounds fired
normally, even with WLP rather than magnum primers.  Five rounds went into
about an inch and a quarter with the other five spread pretty badly -- this
happened twice so there is some potential.   Noise was less than that of a
.22LR and recoil about the same. 

For reasons that I do not yet fully understand, the cases did not exhibit the
typical blackening of low pressure rounds but instead seemed to have bullet
lube blown back on them.  Unburned powder, as is typical, was considerable.  

I will go to heavy and very heavy bullets next, prior to adding a priming

God Bless!


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