6.5 Carcano gas checks

[Mark Daiute]

what size gas checks are you using in your 6.5 Carcanos?

Thanks,

Mark

[swheeler]

? 6.5 or am I missing something, sure I am.

[Mark Daiute]

the bullet is .269. I have .270 gas checks. They go through a 269 die pretty hard

[swheeler]

At that diameter you are going to need the 270 gas checks, the Hornady 6.5mm ones I have here measure .265-.266. Interestingly I have a box of .270 sized cruise missle bullets for the Carcano, they are sized and checked and the checks measure .270, so I too used 27 cal gas checks.

[muskeg13]

6.5 Hornady checks worked fine for me. I recently cast a batch of Lee Cruise Missiles, used the Lyman check seater, and then sized to .269 without thinking about using larger checks.

[Mark Daiute]

6.5 Hornady checks worked fine for me. I recently cast a batch of Lee Cruise Missiles, used the Lyman check seater, and then sized to .269 without thinking about using larger checks.

I was thinking of going with a smaller gascheck thinking they would go through the die more easily than the 270 check

[Gtek]

Anneal the gas checks

[swheeler]

6.5 Hornady checks worked fine for me. I recently cast a batch of Lee Cruise Missiles, used the Lyman check seater, and then sized to .269 without thinking about using larger checks.

So what size do your gas checks measure after going through the .269 die?

Muskeg, if your gas checks are smaller than your guns groove diameter they aren't working. They are not going to bump up to groove diameter at cast bullet loading.

[DonHowe]

Since the .270(.277") gas check is made to fit a larger shank than that of a 6.5mm bullet. What keeps a .270 check properly in place on the shank of a 6.5 bullet until it is sized down?
Just asking...

[swheeler]

There is supposed to be .001" difference in shank diameters, there can be that much difference in individual molds, maybe close to that from alloy differences. I think a 6.5 Hornady gas check ran through a .269 sizer will result in a loose check of diameter smaller than the bullet, then it isn't doing it's job.

[swheeler]

I was thinking of going with a smaller gascheck thinking they would go through the die more easily than the 270 check

It's quite a sqeeze for the 270 gas check which measures( Hornady #7050) .280 at base and .283 at crimping edge v( Hornady #7040) 265 at base and .267 at crimping edge. As Gtek says anneal them and they will draw down easier, grip better too no spring back.

[Mark Daiute]

thanks all, will anneal some, will simply put them on the glass stove top, turn up the heat and then shut it off. Should be interesting.

[Larry Gibson]

Trade the .277 GCs for 6.5 GCs. Most all 6.5 moulds are made for 6.5 GCs.

[swheeler]

6.5 Hornady gas checks are not big enough in diameter, not the ones I've got anyways.

[Larry Gibson]

Just measured 10 Hornady 6.5 GCs. They ran .273 to .274.

[muskeg13]

So what size do your gas checks measure after going through the .269 die?

Muskeg, if your gas checks are smaller than your guns groove diameter they aren't working. They are not going to bump up to groove diameter at cast bullet loading.

I haven't loaded any of the sized and lubed bullets yet, while awaiting a proper sized shell holder, so I just took a few measurements. Either the Buffalo Arms .269 sizer is actually .268 or my Midway micrometer is off 0.001. That's probably ok. My groove diameter was .2675/.268. Sized bullet diameter is .268, AND the sized gas checks are..0.266. Hmmm? The checks are on tight and can't be pried off with my thumbnail. I cast these bullets before Christmas, slugged the bore and set them aside waiting for the custom sizing die. I don't think I installed the checks with the .266 die in place, but that could have happened and would explain tight .266 checks.

I ran into another problem. The closest shell holder I had was too loose (and a Lee shell holder was supplied with the loading dies). In trying to full length size new PPU brass, I stripped the rim from the first case, leaving it stuck in the die. That's always fun, not! On closer inspection, I was surprised at how thin Carcano rims are. I'm waiting on a proper Hornady shell holder from Grafs before loading. Only then will I see if the checks now installed are a failure. Based in Internet research and extrapolating Venturino cast data from his Shooting WW2 Small Arms 6.5 Arisaka data, I plan to load 15 grains of 5744 to start with.

[swheeler]

I haven't loaded any of the sized and lubed bullets yet, while awaiting a proper sized shell holder, so I just took a few measurements. Either the Buffalo Arms .269 sizer is actually .268 or my Midway micrometer is off 0.001. That's probably ok. My groove diameter was .2675/.268. Sized bullet diameter is .268, AND the sized gas checks are..0.266. Hmmm? The checks are on tight and can't be pried off with my thumbnail. I cast these bullets before Christmas, slugged the bore and set them aside waiting for the custom sizing die. I don't think I installed the checks with the .266 die in place, but that could have happened and would explain tight .266 checks.

I ran into another problem. The closest shell holder I had was too loose (and a Lee shell holder was supplied with the loading dies). In trying to full length size new PPU brass, I stripped the rim from the first case, leaving it stuck in the die. That's always fun, not! On closer inspection, I was surprised at how thin Carcano rims are. I'm waiting on a proper Hornady shell holder from Grafs before loading. Only then will I see if the checks now installed are a failure. Based in Internet research and extrapolating Venturino cast data from his Shooting WW2 Small Arms 6.5 Arisaka data, I plan to load 15 grains of 5744 to start with.

Muskeg I had this exact same thing happen Lee dies and Graf 6.5x52 brass, it sucks! I bought a RCBS shell holder for 35 Rem I think it was and it works fine now. I too run out of gas check being big enough somewhere around .268? .252 shank+.008 each side gc+.008= .268" my gc shank only casts .251 so I can get up to .267. I switched to 270 gc so I can size to .270". Now I'm not saying 6.5 Gator checks or some homemade 6.5 aren't thicker but I got Hornady.

edit: It is an RCBS #9 shell holder and works perfect

[swheeler]

Just measured 10 Hornady 6.5 GCs. They ran .673 to .674.

Those are some mighty BIG gas check there Larry!

[muskeg13]

It's not like I've got much going on in the middle of an Alaskan winter during Covid times with the high temp today all the way up to 10 (above), so I took a few more measurements and seated 3 checks on unsized and unlubed Lee Cruise Missile golf pencils. With my soft alloy (ww/a little tin), from memory, I think they ran about 170gr and had an unsized diameter of .271. The shanks are .249- to almost .250. My unsized 6.5 Hornady gas checks have an inside diameter of .250 and an outside diameter of .272 to almost.273. I seated 3 checks with the Lyman tool, and made sure the .269 sizer was in place. Sized checks ran .269, just like they are supposed to. That means I had the .266 sizer in place when I seated the checks before Christmas. I can salvage the 30 done that way by sizing again to .266 and use them in one of my 6.5 Swedes. Back to the Carcano: Hornady checks sized to .269 are on average to a slight bit loose. By that I mean one was a little loose, but not enough to fall off, one was on tight enough that I couldn't dislodge it with a thumbnail and one could be pried off with a thumbnail if I worked at it. About average.

Could it be that you're having problems with 6.5 Hornady checks, and I'm not, due to slight variations in the shank diameter of the Lee molds and in using different alloys. If I sized mine any larger than .269, my Hornady checks would be too loose.

[swheeler]

It's not like I've got much going on in the middle of an Alaskan winter during Covid times with the high temp today all the way up to 10 (above), so I took a few more measurements and seated 3 checks on unsized and unlubed Lee Cruise Missile golf pencils. With my soft alloy (ww/a little tin), from memory, I think they ran about 170gr and had an unsized diameter of .271. The shanks are .249- to almost .250. My unsized 6.5 Hornady gas checks have an inside diameter of .250 and an outside diameter of .272 to almost.273. I seated 3 checks with the Lyman tool, and made sure the .269 sizer was in place. Sized checks ran .269, just like they are supposed to. That means I had the .266 sizer in place when I seated the checks before Christmas. I can salvage the 30 done that way by sizing again to .266 and use them in one of my 6.5 Swedes. Back to the Carcano: Hornady checks sized to .269 are on average to a slight bit loose. By that I mean one was a little loose, but not enough to fall off, one was on tight enough that I couldn't dislodge it with a thumbnail and one could be pried off with a thumbnail if I worked at it. About average.

Could it be that you're having problems with 6.5 Hornady checks, and I'm not, due to slight variations in the shank diameter of the Lee molds and in using different alloys. If I sized mine any larger than .269, my Hornady checks would be too loose.

Muskeg, that sounds very likely, think 6.5 molds are speced out for a .252 gas check shank. I too have cruise missle aka golf pencils sized at .266 for Swede and .270 for Carcano. It also sounds like your gilding metal is .012 thick( that could be flare on the check mouth though) and mine is .008 thick. I guess the important thing is as long as they are tight and atleast groove diameter then accuracy problems are not from the gas checks. Enjoy that Alaskan winter! perfect time for loading ammo!