New Guy Questions for Cast Bullets in 1918 Carcano

Hello. New to casting and fairly new to handliading itself. What finally convinced me to start casting was this 1918 Carcano Troop Special. Favorite rifle I've had, mostly due to how light and handy it is. The bore is good but my issue is the groove to groove diameter measures .270" after slugging. It is my understanding that a .271" bullet would be optimal, correct? If I have a sizer made, can I size down a .277" cast bullet meant for a .270 Winchester? If so, what has checks would I use? I am also considering buying a mold from Midsouth Shooters for the 6.5 Swede that drops a .268" bullet, having the mold machined so it drops one over .271" and then resizing the bullet to .271". Also, how to go about enlarging the neck from .264" to .271"? Would a standard Lee 6.5 Carcano bullet seating die and full length case sizing die work?

Size to throat diameter or 1/2 thou under.

Hi, first post I see, welcome to the forum! A person -- or several of them -- are bound to have the answers to your several questions.
My opinion is that you could size down a .270 cast bullet to work, as the .270 Win. is supposed to be .277 and you're looking for .271, so a total reduction of .006. What you'd have to consider is exactly which of the many .270 Win. molds/bullets would be best suited for the task, with attention to grain weight of the bullet and deformation of lube grooves that might occur from the sizing movement of the lead. Also, the compatibility of the weight of the bullet with the Carcano cartridge and bore. Does your rifle have the gain twist rifling? As for a gas check, I think that the standard 6.5 mm would work for you. Maybe not on all molds, but most likely on many of them. I also believe that your idea of enlarging a 6.5 Swede mold to .272 or 3 would work, but again I would consider the grain weight when buying a mold. As for enlarging the necks to accommodate the .271 bullet you propose to use, I'd go with first annealing the necks to as soft as possible, and then using a custom expander ball for the sizing die. I've found these to work best if the ball is tapered on both ends for an easy in and easy out, assuming that you're using a stout bench press on the order of a RCBS Rock Chucker and a little lube inside the necks as well, of course, as on the outside of the case. As for a standard Lee sizing and seating die set working, I can't say. But what I'd do is telephone or e-mail Lee and ask them. My bet is that it would, but perhaps it would take a little customization. One of this forum's advertisers is Lee, and they have a link to click on at the top of the page.
Good luck with your project -- get back to us and let us know how it all turns out.

Welcome to CB.GL Forum!
:)

I have little to no info for you about your 1918 Carcano Troop Special rifle. I posted really just wanted to say, "Welcome!".
:)
I will say, like mentioned above by DG, you will want to be at least .271" for a cast boolit, if your bore is slugging at .270".

You should also consider getting a mold maker to make you a custom mold for that rifle, even though there is a "cost factor" involved. In the long run though, it might be just as good as dealing with mods & such to get to where you want to be..

If you modify any of the GC boolits, that are smaller than your bore size, like the 6.5 Swede, making a 6.5 Swede bigger, you will likely not gain any advantage since the GC will still be the same as for the bore of the boolit you are sizing. Meaning if you make a 6.5 Swede boolit larger to your .271, then the base that holds the GC will still be the same size as the 6.5 Swede( around .264") & it's smaller base diameter for the GC, to match for a 6.5 Swede, and be less than the .271 bore you are trying to seal.
It will then be the lead of the boolit instead of the GC that is going to get the effect of the powder & riding the rifling & then you would only be wasting the time & $$ on the GC costs & installation for the most part.

If you go the other route using a .270 Win. at .277", then the GC would be larger than necessary & no longer work for your .271 bore. Then you are back to the lead riding the rifling instead of a GC.

Like I mentioned, I think "I" would look to get a custom mold. ( Keep in mind that Lee Precision charges $250 + mold cost to make one though, as an example.)

Getting a regular mold & modifying it to get to where you want to be at .271 & then dealing with adapting for GCs might end up costing you just as much in the long run.

Lastly, I will mention that getting a smaller mold, then "bumping up" the boolits, and adding a PC( Plastic coat) layer might get you to where you want to be as an alternative you may want to consider.
Perhaps a 6.5 Swede mold @ .268, then bumped up & PC'd without/sans GC, might get ya to where you want to be as well...
;)

G'Luck though! & I wish ya the best in getting to where ya want to be.
:)

Thanks everyone. I've just got the standard Lee press. Will have to look at the rock chucker, will my Lee tooling fit it? Funny thing is I bought the Carcano only because it was cheap, as an investment. If a mosin can gain value over just a couple years, anything can. Now I fell in love with the dumb Carcano and have got a 1900 Cavalry Carbine on the way. I have talked to Hornady and their 6.5mm gas checks will seal up to .271" groove so I should be good at .270". The .277" sized down gas check issue is about what I figured, just wanted to verify. Yep, they're both gain twist barrels. Think the original bullets were 130? grains so the mold I have been looking at (168 grains) may be less than optimal now that I think about it. May very well have to have a custom mold made. Der-Gebirgsjager, I also was thinking .272" or .273" that way i can still size to .271 and not worry about any being undersize due to changing alloys. I suppose if I do have issues with gas checks I could have dies made to make my own but hopefully the Hornadys will do.

Whoops. Looks like the original bullets were 162 grain. Maybe the 168 grain may be not so bad.

Attachment 235932My M91 Carcano likes the Lee `Cruise Missile` bullet, but only when cut down to 150gn and cast at .269.

I couldn't get the original 170gn bullet to work.

My most accurate load was around 1500fps, which meant that gas checks weren't necessary.

To fix gas checks to the cut down bullet, I had to fix them with a drop of LokTite thread lock, as there is not enough diameter in the lube groove to crimp them to. Attachment 235944
ukrifleman

Quote:

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Originally Posted by ukrifleman

Attachment 235932My M91 Carcano likes the Lee `Cruise Missile` bullet, but only when cut down to 150gn and cast at .269.

I couldn't get the original 170gn bullet to work.

My most accurate load was around 1500fps, which meant that gas checks weren't necessary.

To fix gas checks to the cut down bullet, I had to fix them with a drop of LokTite thread lock, as there is not enough diameter in the lube groove to crimp them to. Attachment 235944
ukrifleman

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Great to hear from someone else with a Carcano. Very nice grouping. That mold looks like it stated as the one I was looking at for 6.5 Swede. So you just machined off the last ring and the lube groove becomes where the gas check is attached?