20 VarTarg Fire Forming Load

[jcm24m]

I’m wanting to fire from some Remington 221 factory brass into the 20 VarTarg using the 32gr Blitzking. I will be using Vit N-120 and CCI 450 primers. I’m thinking about 17 grains. What do you think ?

 

[TheCZKid]

I have to assume you are sizing the necks from 221FB to 20 caliber, probably with a FL sizing die or bushing die?
You might need to verify the neck thickness on that brass, make sure it isn't too thick to load without turning the thickness down, before you load your tests. If you have a .232 diameter neck, then you probably will need the neck thickness to be .0120" - .0125" thickness, and maybe as thick as .013" might work okay.

I got some once shot Remington brand 221 FB brass with my rifle from the original owner. I measured the necks, and they were from .0125 to .0150 thickness, and I'm amazed they let the bullet go very easy when he used the, without turning them. When loaded they would be about the same diameter as the chamber, no clearance to let the neck expand!

A good general rule of thumb is, the outside of the neck with the bullet seated in a 20 caliber, should be .0128" overall diameter. If you have a .232 neck you have .002 clearance all around. If you have a .234" neck, you might get away with .0135 thick necks, and so on.

As to your load, Vit N-120 at 17 grains with a 32 grain bullet is probably going to be very close to a final load. Of course, start a bit lower and work up. As far as CCI 450 magnum primers, might work well. If you have Remington 7 1/2 that's another good one, and CCI 400 too. The person I purchased my Vartarg from liked N120 17 grains and Winchester SR primers as the best load.

 

[SeabeeKen]

N-120, LT-30, and A-5744 shot best in my 20VT with 32 gr Sierras of the 11 powders I tested. Not that the others shot bad, (no group over .6") just these shot best. In the end, I went with 32 gr Berger which couldnt do any wrong with the same powders