MP 45-270 SAA woes?

[lar45]

Hi everybody,
I just picked up a MP 45-270SAA 4 cavity brass mold that was slightly used. The mold is absolutely perfect and casts very uniform .454" bullets from range scrap, 9.8 Brinell.
This is my first go around with the 45-270SAA design, but I've always read good reports on it.
I sized a pile of them to .452" and lubed with 2500+.
I loaded up a bunch with Unique, 2400 and 296 in Starline 45 Colt brass primed with WLP primers.
To test them, I shot them through my Taurus Raging Bull 454 with a TC 2x scope mounted on it. I hung the targets at 75 yards and shot from a sand bag rest.
The Unique group was terrible, the 2400 group was terrible, the 296 group took up 2 sheets of paper.
I wasn't sure if the scope was bad or loose, or maybe I had forgot how to pull a trigger, so i pulled out some of my standard 45 Colt loads with a 275 LFN loaded with 22gn H2400 and shot some of those. That is the target on the right and it looks fairly good for my old eyes with a 2x scope with the sun going down.



Any thoughts?

[DougGuy]

For the record, the Raging Bull cylinders that have come through my shop for throating have some of the worst throats in the industry. Barreled, egged, nothing about them round and nothing parallel. When I hone these, and the stone first makes contact, it wants to grab the cylinder and THROW it across the shop. That's how bad out of rounds they are. Not that this will be the root cause of your groups, but it sure can't help matters.

[376Steyr]

Is this the first SWC you have tried in your Taurus? Some revolvers won't tolerate SWCs, but like round noses. I have a .45 Colt Ruger New Vaquero that makes patterns with Keith-type bullets, but groups quite nicely with 230 round nose loads.

[lar45]

With a good bullet and load the gun has shot some interesting groups with 3 shots touching and the other 2 are farther out.
These targets were shot at 50 yds.
320gn LFN style plain base at about 1350fps with WC820

350gn SWC plain base with the same load.

[black mamba]

I'd say just keep trying different combinations of loads. My 5" Raging Bull 454 is the most finnicky revolver I've ever owned. Some loads are astoundingly accurate, while others shoot patterns, not groups. I've had as little as a half grain difference in powder charge move a group from 3½" to 1½", and then another half grain open it back up again. For what it's worth, my own best groups with the 270 SAA were with 10.0 gr. of Silhouette and magnum primers.

[Thumbcocker]

In my experience that boolit is all hat and no cattle. Lots of gunscribes ooooed and aaaahed over it but my experience has been that a Keith boolit shoots rings around it. YMMV

[35 Whelen]

There's nothing wrong with the 45-270 bullet. My Uberti Frisco shoots it lights-out-



I shot a buck at 41 yds. with one a couple of years ago and as impressed by the damage wrought by a bullet lumbering along at 950 fps or so-





I'd say you have a revolver problem, not a bullet problem.

35W

[cupajoe]

I have had good accuracy with that bullet in the RCBS mold, I wonder if Miha strayed from the RCBS design a bit too much.

[DougGuy]

lar45, I would suggest sending the cylinder and let me get a look at it. It isn't going to fix itself.

[Dan Cash]

Any idea why the former owner of the mould wanted to sell it?

[475/480]

Seems to me might be too much pressure/velocity for that boolit. Back down on the load

Sean

[kingrj]

My friend..I am afraid you need a new gun...