203 powder

[maddysdad]

what is the diffeance between 203 and 203b powder.

 

[RustyInBend]

Clearly it's the letter "b".

 

[KMart]

Just throwing a WAG out there.
I have never seen Norma 203 powder advertised or sold, but it appears on some burn rate charts. It may not be manufactured any longer, but may have been their first attempt in a powder in that burn rate zone.
Norma 203b, even though nobody can find it now, is currently produced. Norma most likely made a formulation change on 203 and changed its designation to 203b.
203b and Alliant Re 15 have very similar loading characteristics.

 

[Doom]

Norma Powder numbering standrad was by burn rate beginning at 200 to 204 but deviated with MRP. Originally there was a Norma 203 but that powder formulation/process was slightly revised so instead of giving the powder a new name they added B to the powder name to indicate the new powder.

 

[SeabeeKen]

Alliant Reloder 15 Vs. Norma 203B — The Numbers Tell All « Daily Bulletin

In response to our Bulletin story about the availability of Norma powders at Midsouth Shooters Supply, one of our Forum members asked: I'm having trouble finding Reloder 15 for my 6.

bulletin.accurateshooter.com

 

[choprzrul]

I wonder if Norma intends to distribute powder in the US again anytime soon?

 

[243winxb]

If you look thru the photos of powder, one is darker in color then the other. https://www.ilrc.ucf.edu/powders/sample_detail.php?powder_id=1
The B could mean the powder has been made darker for the USA?
I think it was ADI that made 1 of there powders darker, just for us.

Found it.

 

[Laurie]

It may not be manufactured any longer, but may have been their first attempt in a powder in that burn rate zone.

Spot on. It's a long discontinued line that was eventually replaced by the current 203-B. According to R H VanDenburg Jnr in Handloader's 2004 review of the powder, N203 was discontinued way back in 1977 having been found to be too difficult to manufacture consistently. It was initially replaced by (the still ongoing) N202, but 203-B followed some years later to fill the rather large gap between 202 and 204 burn rates.

As far as I'm concerned, Alliant Re15 and N203-B are the same things. I ran side by side tests of the pair in a 223 F-Class rifle last summer and achieved identical results over six by 4-round rising weight batches each for the pair - groups, MVs and ES values. Apart from one single charge weight that saw a 20 fps discrepancy (at 3,000 fps with the 77gn Sierra MK), the pair produced average MVs varying only by single figures. Given that the 203-B used was a 'fresh' lot, and that the Re15 was likely around 10 years old, the pair were remarkably close and consistent. Alliant ATK's man on this forum says that his company's version (Re15) is held to tighter performance tolerances than the Norma's.

It's very common for powders to remain in burn rate tables and QuickLOAD long, long after their demise. Alliant Re12 (from the same source, Bofors in Sweden) was withdrawn around 20 years ago after a relatively short life, but still appears regularly in such sources.

 

[maddysdad]

n 203 was used by a bench rest shooter in the 22 br back in the 70s i think.with it and remington 52 grain br bullets he shot a record agrugate of .1776 i think.