A project I've been working on for a long while has finally come to fruition: building a Pistol Caliber Lever Action Silhouette gun that I could also use for the center fire Lever Action Silhouette if I wanted. The goal was to use a Rossi 92 in .357 with a cast boolit, and and I wanted to be able to shoot 2.5 MOA off a rest with a silhouette legal set of sights pushing a 158 grain bullet at 1800fps. I knew from shooting my very accurate K31 with GP11 ammo that I'm capable of 2 MOA with iron sights, and figured another 1/2 MOA for it being a lever gun. I've been able to meet and exceed those goals, as you'll read below. I'll divide this post in several sections detailing what I settled on regarding work to the gun's action, sights, and load.
Action Work:
Shortened the mainspring. Shim underneath the trigger leaf. That's it. This makes the gun's action very smooth and lightens the trigger enough. Easy info to find on YouTube (for now! - move all your gun videos to Full30!).
Sights:
For a while I was using a Marbles 95 rear sight with their .571 high front sight with the 3/32 brass bead filed on each side to make it .065 wide, and also flattened on top. I was shooting fine groups with this, but wanted to try a peep. I got Steve's Gunz bolt-mounted safety replacement peep sight and I *really* like it. Like many others I was not pleased with the fit of the steel insert into which the sight is screwed. Steve will tell you that he has to account for Rossi's wide tolerances in making the channel for the pin. Some guys re-cut their own channel - I found it much easier just to put an o-ring underneath the flange on the top of the insert. Snug as a bug in a rug. I'm using the Fine aperture. Good for everything except shooting in the direction of the sun if it's lower in the sky.
For the front sight I ordered the .650 tall replacement from Skinner, in the .375 width dovetail, 1/2" base width. I narrowed the blade to be .065 wide and shortened the sight to .48 inches. I filed the dovetail on each side until I could push the sight back and forth in the dovetail slot of the gun with steady thumb pressure. I then drilled and tapped a #6-32 hole on each side of the blade. This allows me to put a set screw in each hole which I can back out and then I'm able to move the front sight easily for windage. I found that a screw on each side of the blade was necessary so that the cant of the front sight blade could be properly set. Drilling and tapping was new to me and I managed to break a tap on one of my practice holes on another front sight. The rest have gone flawlessly after I started to use proper tapping oil and a lot of backing out of the tap as I went (most of you will know this lesson already - give me a break, I misspent my youth learning Greek and Hebrew instead of being in shop class!).
Mold, alloy, gas check, powder coat:
The Rossi 92 is famous for its slow twist rate of 1:30. If you plug this into the calculators online (http://www.bergerbullets.com/twist-rate-calculator/), you'll find that you need a pretty short bullet going at a decent clip. **Don't rely on weight as a proxy for the length of the bullet.** For example, the differences in the length of the three Lee molds casting 158 grains makes a big difference in stability at 357 carbine velocities! The clear winner among those four designs is the 358-158-RF, which also had good reviews from a lot of people. That design maximizes weight in a length that the Rossi can easily stabilize at the velocity I was looking for (1800+).
Powder coating has been a revelation to me, and to many others, and allows me to hit those velocities easily. I'm casting in a pretty soft allow. A 3B Pencil will not scratch it, but a 2B Pencil will...so let's call it 10.5 BHN. They drop nice and fat from the Lee mold at .360 and 157-158 grains. I shake and bake powder coat with a TGIC free powder (Powder by The Pound Steel Blue RAL 5011-S) and stand the bullets up to cook. I then size them with a .360 Lee die (which started life as a .359 die before I used the sand paper, dowel and drill trick).
Just recently I started gas checking these with plain based sized aluminum gas checks from Sage Outdoors (~$30 shipped for 1000). They don't "click" in like a proper gas check on a proper gas checked bullet design - but a friendly tap with a soft mallet squares them up in the check just fine. I then push them through the .360 Lee sizing die base first. This works well with this bullet design's flat nose. You'd need the appropriate nose bushing for any other design. Or you might try the collet crimp die trick to seat them...because it does not work pushing them through the die nose first: you end up with a flange of aluminum on the circumference of the base. After the gas check is affixed, I shake and bake with the powder coat as narrated above and then resize to .360 nose first.
The Loads
WARNING. THESE LOADS ARE HOT USING MAXIMUM DATA FOR JACKETED BULLETS FROM VARIOUS SOURCES; FOR INFORMATION ONLY; IN OTHER WORDS: DON'T USE THESE LOADS. Or at least don't blame me. I don't shoot them in anything but this Rossi 92 which is famous for having a very robust action.
BOTH OF THESE LOADS EAT BRASS UP in the lever gun's action: the bolt has enough slop to allow a lot of stretch on the long axis of the case. Watch for case head separation as it will eventually occur if you keep reloading the brass: one day you'll work the lever and a nice little case head will fly out with the rest of the case stuck in the chamber. It hasn't been a big deal when it does occur - a bore snake passed through the muzzle end pulls them out just fine 99% of the time. For that 1% tricky stuck case try three cleaning patches on a brass jig and tap the cleaning rod down with a mallet. I'm switching over to all Winchester brass-colored brass as they seem to hold up the best. Starline brass is THE WORST. On the second or third reloading of this load they will separate. All nickel colored brass seems to be weaker than the Winchester brass-colored brass as well.
The load without a Gas Check:
158 grain bullet powder coated as noted above, seated to crimp groove, Lee collet crimped nice and solid (a bit more than the 1/2 turn they recommend you start with). 17.0 Grains of H110 and a mag primer. LYMAN 49TH GIVES THIS AS A MAX LOAD FOR A JACKETED BULLET OF THE SAME WEIGHT. It chronographs at 1830 fps. I shot a 70 yard, five shot group at 1.8" for ~ 2.5 MOA. Goals achieved!
The load with a Gas Check:
158 grain bullet powder coated as noted above, seated to crimp groove, Lee collet crimped nice and solid (a bit more than the 1/2 turn they recommend you start with). 17.6 grains of H110 and a mag primer. LYMAN 46TH GIVES THIS AS .1 GRAINS UNDER THE MAX LOAD FOR A JACKETED BULLET OF THE SAME WEIGHT. It chronographs at 1880 fps. I shot a 70-yard, five shot group that was a clover leaf, plus a fourth under 1", plus a centered but vertically strung flier that pushed the overall 5 shot group to 1.48.
I'm calling that 2 MOA! Goals exceeded!
Pastor Curtis
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