View Single Post
Old November 29, 2011, 05:17 PM   #3
Unclenick
Staff
 
Join Date: March 4, 2005
Location: Ohio
Posts: 21,013
It the same. I get that both from talking to Hodgdon's technical support and from reading the MSDS sheets. Quite a number of differently named powders are the same thing at the time of manufacture. The military and manufacturers will buy bulk grades that have sometime significant lot-to-lot burn rate variations. The versions sold to handloaders are called canister grade, and for these the maker has gone to the extra expense of testing his lot burn rate than adjusting it by blending with held back lots that turned out to be exceptionally fast or slow, until the net burn rate is, according to Hodgdon's standards, withing 3% of nominal. This is done to keep load manual data valid. With bulk versions it cannot be counted on to be valid, which is why you have to be careful when buying surplus powders, as they are bulk powders and their burn rates cannot be counted on to be close enough to the canister versions to use the manual data.

Below is my list of equivalent powders based on information published in their MSDS's. The ones under military and OEM are bulk grade numbers. Those under handloader powder company names are canister grade versions.

Code:
                   | St. Marks  |                        |          |
     Hodgdon       |  Military  |      Winchester        | Thales   |  IMR
                   |  & OEM     |                        | (ADI)    |
___________________|____________|________________________|__________|_______________________
                   |            |                        |          |
HP-38              |   OBP231   |  231                   |          |
H110 --------------|--- WC296 --|- 296 ------------------|----------|-----------------------
H414               |    WC760   |  760                   |          |
H380               |    WC852   |                        |          |
Lil' Gun ----------|-- OBP516 --|------------------------|----------|-----------------------
Hybrid 100V        |   SHP771   |                        |          |
HS-6               |    WC540   |                        |          |
H335 --------------|--- WC844 --|------------------------|----------|-----------------------
BL-C(2)            |    WC846   |                        |          |
Titewad            |   OBP132   |                        |          |
Tightgroup --------|-- OBP242 --|------------------------|----------|-----------------------
Longshot           |   OBP473   |                        |          |
US869              |    WC869   |                        |          |
-------------------|--- WAA90 --|- WST ------------------|----------|-----------------------
                   |   WXC170   |  WSF                   |          |
                   |   OBP124   |  AALite (WFL)          |          |
-------------------|-- OBP465 --|- Super-Handicap (WSH) -|----------|-----------------------
                   |    WC748   |  748                   |          |
                   |   WMR780   |- Supreme 780           |          |
-------------------|-- SMP224 --|  AutoComp -------------|----------|-----------------------
                   |            |                        |          |
Clays              |            |                        |  AS30N   |
International Clays|------------|------------------------|- AS50N --|-----------------------
Universal Clays    |            |                        |  AP70N   |
H4227              |            |                        |  AR2205  |  IMR 4227 second source
H4198 -------------|------------|------------------------|- AR2207 -|-----------------------
Benchmark          |            |                        |   BM2    |
H322               |            |                        |  AR2219  |
-------------------|------------|------------------------|- AR2210 -|- IMR 8208 XBR --------
H4895              |            |                        |  AR2206H |
Varget             |            |                        |  AR2208  |
H4350 -------------|------------|------------------------|- AR2209 -|-----------------------
H4831              |            |                        |  AR2213  |
H4831SC            |            |                        | AR2213SC |
H1000 -------------|------------|------------------------|- AR2217 -|-----------------------
Retumbo            |            |                        |  AR2225  |
H50BMG             |            |                        |  AR2218  |
-------------------|------------|------------------------|- AR2215 -|- IMR 4198 second source
                   |            |                        |  AS25BP  |- IMR Trail Boss
As to why Hodgdon distributes multiple versions, that's just because when they and Winchester were independently buying and distributing the same blended grades from St. Marks, their load data was separate. As a result, you will find many manuals that only list the Winchester branded version or only list the Hodgdon branded version, and Hodgdon doesn't normally want to lose the business for either data listing by making one of the labels unavailable.

They will do that if the usage is low enough, though. They have discontinued H4227, for example, as the IMR lable product is currently the same thing and the H branding apparently wasn't popular enough to their sales to be worth the cost of keeping it separately inventoried.

BTW, you also get some instances where both Hodgdon and Winchester brands of something are listed, but because the manual author bought test samples that came from different lots, the listed charges aren't quite exactly the same. It's a good way to get a sense of how much lot-to-lot burn rates can affect a powder even with the same label.
__________________
Gunsite Orange Hat Family Member
CMP Certified GSM Master Instructor
NRA Certified Rifle Instructor
NRA Benefactor Member and Golden Eagle

Last edited by Unclenick; November 30, 2011 at 11:18 AM.
Unclenick is offline  
 
Page generated in 0.05050 seconds with 8 queries