303 Gas checks

[jtaylor1960]

What gas checks do I need for the 303 British?I can't remember seeing any listed in a size between .30 and 8mm. I am working on a cast bullet project with a friend that has a Martini in 303. and realized I needed to get gas checks.

[dualsport]

I use the .30 Gator Cheks available here. They're great.

[Three-Fifty-Seven]

I use Pat's Checkmaker in 30 cal on my 314129's fits fine!

[caseyboy]

Same. Use Pat's Checkmaker. 0.012" annealed Al flashing. Fits the 314299 fine.

[jtaylor1960]

Thanks guys.I have some 30's.I was thinking about a Pat Marlin makeralso.How are you annealing your aluminum? Does if have to be annealed?

[Three-Fifty-Seven]

I don't anneal . . . this is what I do:
http://www.youtube.com/watch?v=pP_R6ZjayWU

[caseyboy]

You don't really need to anneal, I just like to make things as complicated as possible.:bigsmyl2: I punch the discs, throw them into a 4" pipe nipple with a cap on each end (don't forget to drill a small hole in each cap to relieve pressure) and toss it into the wood stove. Fish it out after awhile and let the whole works cool to room temp. Then I form the cups. If I didn't anneal, I would occassionally tear a few cups when forming them.