Each bullet hole shows a lube smudge on only one side of the hole, indicating an unstable bullet. The further out it goes, the more unstable it is likely to become. I'm not the only one to have had this problem. Our own Sixgun wrote about it in a thread from over a year ago:
http://www.levergunscommunity.com/viewt ... =1&t=40746
There's a fellow called Remington35 over on the Marlin Owners forum who has very thoroughly wrung out the .25-20, including using the RCBS bullet. He points out that it is a long bullet with two deep grease grooves meant to carry a lot of lube for shooting black powder. He suggests casting them very hard, water quenching, then Alox lubing to avoid the problem of excess lube. That sounded like a very reasonable observation to me, so I gave it a try. No joy, at least not for me. The yaw was still there.
So I'm sitting there looking at this bullet mould and thinking about what this guy had observed. Yep, it's long for the caliber. Yep, it has two deep, wide grease grooves. I'm not having any luck making it shoot straight. Right then and there, I got a notion. Why not just cut off one of those lube grooves? I used my dial caliper to determine that a cut of .175" would do the trick. I pulled the handles and sprue plate off the mould and took it to my brother's machine shop, and in a matter of minutes he removed the sprue plate stop pin, squared the mould up in his milling machine, and deftly shaved it off. Here it is right after the trim job:
I cold blued the raw surface, and was pretty pleased until I went to put the handles back on. For some reason RCBS has changed from a single long screw holding the handles on each half to a loose pin held in place by a following set screw. The cut had exposed the handle pin holes, and now the pins wouldn't work! Not to worry, I had some of the old style screws in my stash, and they worked just fine. The sprue plate bolt would also have to be shorted to accommodate the shorter mould blocks. No problem, just get out the hack saw. Here's a picture comparison of the original hardware on the right and the replacement hardware on the left, as well as another picture of the finished modification:
The bullets cast from the modified mould went from weighing 85 grains down to 63 grains. Here's a side-by-side comparison:
Best of all, the new shorter bullets show no evidence of yaw. They make nice even holes in the target paper.
I tested them on my metallic silhouette practice targets, Chicken at 40 meters, Pig at 50 meters, Turkey at 75 meters, and Ram at 100 meters. Load was 5.5 grains 2400 with a Winchester small rifle primer, shot from a rest. I was very pleased with how tight the group was on the 100 meter Ram:
I think I might just give this bullet a try at the silhouette match this weekend!
SHASTA
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Those bullets shoot in to a little over an inch at 100 meters. The best cast bullet load I ever used was the bullets that Steelbanger sent me. ....70 gr. Ranch Dog........but I have since shot those up. The Lymans will do 3".....ok for club shoots but I want the best at the big shoots.
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