Norma Brass Question - 7mm mag

[Juano86]

G'day All,

I did a bit of a search on the subject but couldn't find what i was after, so pardon if this has been covered.
I Just purchased a new T3X Superlite in 7mm Mag and im just beginning to work up some loads. However, in my reloading manual it suggests that if using Norma Brass to reduce the powder by 10% to counter the heavier brass. Is this something i should be wary of?
Im using ADI AR-2217 powder (Not sure what the US equivalent is, ADI are saying its close to Hodgdon H1000). A max load for a 140gr projectile was 70gr, but shaving 10% seems like a lot. to develop the load id obviously use the ladder method and check for pressure signs etc. but reading that note made me wonder...

Any advice? Struggling to get RE-22 over here (in Australia), that would have been my first choice as a starting point.

Cheers in advance.

 

[AZShooter]

I agree 63 gr which is 10% below 70 grs does seem too low. I would start at 65 gr which is two grains below what Hodgdon suggests as the starting load on their loading page.

http://www.hodgdonreloading.com/

That should be low enough. I am sure you will breeze right past it and get close to the max with your brass. I believe the reloading book author's are just being careful in these litigious times.

While H1000 will work and be stable with temperatures would not have been my first choice for powder with a 140. But you use what you can get.

 

[Juano86]

Thanks for the feedback. Probably was thinking of starting at around 65gr making my way up.
The only powder i can get my hands on lately is:
ADI AR-2209 (Hodgdon H414/ H4350 equivilant) - i use this in my .25-06.
ADI AR2213SC (Hodgdon H4831 equivalent).
Trying to place an order for some Alliant reloder-22 but could be a while!

 

[Remmy700]

Yeah I would think that is pretty lite load to start off with. I am using 180 bergers in my 7mm RM with Norma brass and my pet load is 69.3gr of H1000 and have went up to around 71. Mind u this rifle was built for 180s at AI 300 win mag length so I have ton of room for powder. Lot of it's going to come down to how deep u are seating. U should be pretty good as the 140s are pretty short in comparison.