Gas Checks and powder

[Marduk]

I am planning on casting some 170 FN for my 30-30 and and the Lee manual has reloading data for a 170 Lead Bullet. Question is, does adding a gas check to the bullet affect this data in any way?

I assume it is still a 'lead bullet'? (ass-u-me ???)
Do I stick with the 170 or do I need to weigh the bullet with the gas check on and do some fancy ciphering?

As always, thanks!

 

[Rangefinder]

Nothing changes---load it on the 170gr data.

 

[454PB]

I read somewhere that HP White laboratory did some pressure testing many years ago on .44 magnum ammo and found that gas checks do increase pressure. You should be building a load from below, so it shouldn't be a problem.

 

[Marduk]

Thanks guys!

 

[grubbylabs]

It is pretty standard to load the same as a plain base bullet.