There is presently nothing I can find on the internet about this so here we go!
I used a steel clip since the brass ones are much less common - and more expensive!
You will need a dremel with cut off wheel and a pair of pliers. I suppose you could try a hacksaw for the necessary cuts, but I think it will be a bit much.
The first pic shows an unaltered steel clip with 5 rounds of cast bullet reloads. A brass clip with vintage ammo is shown for comparison.
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An 8mm round won't fit into the clip and sliide into place, so I used a Dremel tool with cutoff wheel to relieve the web on the back of the clip.
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I also used pliers to gently pry the lips apart just a LITTLE to make it easier to slide a round in.
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The clip now holds well one round and it fed just fine on multiple tries. If you wish, you can stop now and have a one shot clip which will preserve your extractor from improper single loading.
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zzClips 005.jpg [ 111.13 KiB | Viewed 57532 times ]
But since I had already altered the clip, it was time to see if 5 rounds would work. I used the Dremel again to completely cut the top web. That really didn't help that much. I now had a 3 shot clip, so I cut the bottom web about half way.
**NOTE** leave the center web alone!
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I also used the screwdriver tip to GENTLY pry the sides of the clip apart at the web. Don't get carried away with this.
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The rounds still wouldn't slide up & down in the clip like I wanted, so I widened the clip opening with very slight thumb pressure. This helped a little, but now I only had a 3 round clip. Rounds 4 & 5 had to be pushed up from the bottom with the screwdriver blade. Not what I had hoped for.
A 3 round clip is an improvement, though and if you start with one in the chamber, you have a 4 shooter. Not wanting to mess up a usable clip, I really didn't want to do anymore cutting & prying... but it occurred to me I had nothing to lose putting the clip in the other way.
It worked!
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Here you see the clip after the final adjustments. One web is cut clear through - the bottom web is cut about halfway. The center web has been left alone. I pried the clip apart just a LITTLE and used pliers to open the lips slightly as shown above. It feeds 5 consistently.
Finished product is shown by the brass clip of 6.5 for comparison.
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I loaded 5 rounds into the end with the web cut about halfway and stuffed the clip into the magazine with the fully cut end going in first.
Please keep in mind this is a cut & try operation. The clips were meant to be expendable. Once used, another was crammed in and the shooter continued to blast away. Which is a long-winded way of saying they are not very durable and can be ruined by getting too vigorous in your adjustments.
So go slowly! Cut and try. When something works like you want - go on to the next step. Work is just crazy right now, but I mean to try another clip with some differences.
If any of you brave souls have different results or better ideas, please post same with pics.
Thus endeth Carcano clip alteration 101!