HAVE I GOT MY SIZE NEEDED RIGHT ?

[orgoniun]

Steve

Could the 309 / 307 numbers be an error ?
Can you tell us what you're using to take this measurement with ?

Most 30 cal. barrels are 308 / 300 or 309 / 301.

The 309 / 307 numbers would make the height of your rifling only .001".

Ben

Ben you are correct, Measured again today and got .309/.301 - Measured with a dial caliper.
Got some sample pacs of GC to play with but am a little confused on the thickness of them, How do I know what thickness to use on my bullets ?

 

[Brad]

Dial caliper isn't precise enough for those measurements. You could easily be .001 off.
As for checks, might need some trial and error there. You want them thick enough to stay on. They need to be firmly sized when running the bullet they the sizer. A lose check isn't doing as much good as a snug one.

 

[Ben]

I'm with Brad, you'll eventually need to purchase a good micrometer.
You can pick up a good used one on Evil Bay for about $20 - $25.

As to gas checks, if you can twist them and pull them off with a finger nail, they will be of questionable effectiveness for you.

 

[Doug]

Guess Mr Target doesn't lie. Yesterday my wife shot a 1/2 MOA on bullseye @ 200 yds w/ our 3d modified mold. Shocking. Yes, I've been to NOE but he doesn't make our sort of bullets so I'm gonna stick w/ our beagled molds for the time being til we can justify buying something custom.

 

[fiver]

check accurate molds.
Tom can make what you want.
you can send him a boolit and if he can make it with his equipment he will duplicate it.
you might get a small flat on the nose since the flat nosed cutters are less prone to breakage but that's a small price to pay for round and same boolits.