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Hi Rigby Mauser
Don't use an existing drawing. Make one that will fit YOUR GUN.
Here's how you do it.

Make a bore casting, or a soft slug imprint of your bore. Then factor in your twist.

The actual weight is not important. What's important is the Sectional density of the projectial. If you have a 1-88 twist for example, you'd make the bullet with a wide meplat and a short ogive of about 1/4 the bullets length. (I would use a .600 ogive)
Now establish your bullets length. (That's why you need to know the twist rate)

Let's say it's 1.125" long That would leave about .930" for the shank of the bullet.
Make the shank so that it's .002 Smaller than the BORE diameter of your barrel, and the top land about .002" larger than the groove diameter. (The lube grooves will give you the lands.)

Make your drawing to give you 2 lube grooves in the shank portion of the bullet, with the bottom groove being 2X wider then the top groove. If I were making the mold for myself, I would make the bottom lube groove about .250" long, and then make the top groove about .100" long.

Now, position the bottom of the bottom lube groove about .200 from the bullets base. Position the top edge of the top groove only about .040 from the top edge of the shank, where the shank turns into the ogive.

When you are done you will have a bullet design that give you very good performance. And it will fit YOUR rifle.

I hope I made this all clear.
If you have questions, write to me a szihn@wyoming.com and I may be able to help you. I would draw it for you, if you can give me your bore and groove diameters, and your twist, and e-mail it to you.

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