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Hank45
11-25-2010, 02:40 PM
Is the old . 28 Caliber boolit desine the same as the modern 7mm? Thanks for your answer, Hank45

felix
11-25-2010, 02:44 PM
Hank, it is best not to think this way at all. Look at the gun's requirements in terms of boolit fit, and then see if the size required exists in a standard something. ... felix

HangFireW8
11-25-2010, 03:43 PM
Welcome to the board, Hank.

Older European 7x57 bores were all over the place in size, while American made 7's (like the Win Model 54) were much closer to the nominal .283 inch. Modern 7mm Magnums are very close to .283 but can still vary by a thousandths or so.

As for your mold, even if you were to post the model number, we have no idea whether it casts large or small. Trying it is the only way to see what it produces.

-HF

runfiverun
11-25-2010, 10:31 PM
designs are designs.
size is what matters.
it's the bbl that determines the size and style you want.
i had an older 7x57 that the groove diameter was 288 in, it needed some serious help and a correct sizer just to get started.
but i could shoot cast in it with much better accuracy than jaxketed would.

geargnasher
11-25-2010, 10:43 PM
Yup, size matters most. As in fit.

Gear

Bret4207
11-26-2010, 08:35 AM
I would add that if you have a really old 28 caliber mould and it's plain based it may be an old tapered design for the 28-30 Stevens.

jameslovesjammie
11-27-2010, 05:26 PM
It would also help if you mentioned what mould you are looking at. Lyman's moulds that start with 280 are for .277 diameter barrels, while their ones that start with 287. Ex: 280468 is a boolit for the .270 Winchester and 287346 is for the 7mm.

runfiverun
11-27-2010, 07:55 PM
some of the old boolits were designed to be bore diameter not groove diameter.

BOOM BOOM
11-27-2010, 08:05 PM
Hi,
7mm=.284,

HangFireW8
11-28-2010, 05:32 PM
Hi,
7mm=.284,

But only in the modern wild 'n wacky world of cast boolits.

For jacketed bullets you're talking .283.

For SAE to SI, it is really something like 0.2755897 inches. (Which means the .270 Winchester is much closer to a true 7mm than any 7mm, at least as far as groove diameter is concerned).

For old 28 caliber rifles, the answer is "depends". This is an English measurement caliber that didn't really make it into the era of SAAMI standardization, back when each rifle manufacturer that made a 28 caliber had its own ideas of what that 28 meant. Colt made a number of early revolvers in 28 caliber. For flintlocks and caplocks, 28 caliber was just a barrel freshening between 26 and 30 calibers. After the freshening, the gunsmith would slug the bore and then cut a mold to match.

So, unless the Original Poster cares to post some pictures, mold & cherry numbers, cast a few slugs and take some measurements, we can debate here forever as to just what that 28 means.

-HF