sizing 308 or 309?

[creekman]

I'm going to be casting lyman 311041 and 311359 for hunting in a 308 Remington Mohawk that has been modified into a lightweight still hunting rifle. The 041 will be my deer load and the 359 will be used as a light load for rabbits, crows, etc. Should I size to 308 or 309? Since I'm not going to be loading a bunch of different calibers I'm thinking of going with the Lee sizer. Your advice would be appreciated.

[GrizzLeeBear]

I would slug the bore first, its very easy. Do a search, lots of threads on how to do it, there was one just recently. Its usually best to size boolits at least .001 over bore diameter. Most modern commercial .30 calibers run right at .308 and I don't think you would have any problem sizing to .309, if anything you might need to size larger to fit the throat. Take a case that has been fired in that rifle and see if a sized boolit will slip into it by hand. This will make sure your boolits are not to big for the case to "let go" of it when fired. As an example, in my Rem. 700 I found that a .311 (dia. they drop from the mold) boolit will not fit into a fired case, so I will be sizing my cast boolits to .309 for this rifle (bore is right at .308).
If you want to go ahead and order a sizing die, I would go with the .309. There is very little chance that it would be a problem and there is a better chance that the .308 sizer might be too small for the bore which would increase the chances of leading.

[Bret4207]

.310 or.311! Go as fat as your rifle will accept. .308 will almost certainly be way too small and.309 is likely to be too. I'd go .311 myself unless you've slugged the barrel and made a chamber cast showing you need smaller.

[fourarmed]

Bret is absolutely right. I have yet to use a sizer smaller than .310. I also noticed recently in Ken Waters' "Pet Loads" a statement that he had found .310 to be the most accurate in the general run of .30 caliber guns.

[Larry Gibson]

Last several suggestions are what I do. I've found through considerable testing that .311" is the best "sizing" for most factory or milsurp chambers in .30 cal rifles. Couple caveats though; if the bullet casts at less that .311 size "as cast". Mic the inside diameter of a well fired case from that rifle. If it mic's larger that .311 then size .311. If it mic's smaller than .311 then size to what it mic's.

Larry Gibson

[docone31]

I paper patch, and size to .309. If it were plain casting, I would go at least .310. If my chamber could handle it, .311.
Bigger is better.

[1Shirt]

Minimum of .310. The only thing I size to 309 is for my K-31 Swiss, which is a horse of a different color.
1Shirt!:coffee:

[bdoyle]

I like to run the largest diameter that will fit in the throat. I lube with an oversize die and then final size with a lee die that I polished out to diameter or a few tenths under the throat diameter, which ever works better. Ususally close to .310. Bolt and lever guns will assist but my single shots only have my thumb to chamber.
Brian