Powder Burning Rates

Powder Burning Rates and Nomenclature

In preparing this edition of the Sierra Reloading Manual, we encountered some confusion relating to the identity or nomenclature of certain powders. This is due in large part to the fact that there has never been any standardization of the abbreviations used by different manuals to identify a given powder. As an example, Reloder 7, a medium-fast burning rifle powder manufactured by Hercules (now Alliant Powder) is identified in Sierra’s loading tables as “RE-7.” In other publications, it has been listed as Re7, RL-7 and RX7. With such similar powder names or designations as Hodgdon’s HS-7 and Accurate Arms’ No.7, the stage has been set for a potentially dangerous situation. In this particular example, the three powders listed (RE-7, HS-7, and AA No.7) are all distinctly different and are not interchangeable. Because of the lack of uniformity between the various publications, we felt that some form of index or legend would prove to be beneficial.

We also now have a situation wherein powders having the “same” numerical designation are available from several different sources. Probably the best example of this is the slow-burning single-based rifle propellant known as 4350. Available now as the original IMR 4350, Hodgdon’s H4350 and Accurate Arms’ 4350, the potential for confusion is obvious. Other powders sharing this same situation are 4227, 4198, 4895, and 4831. Each of these powders is available from both the Hodgdon and IMR powder companies. Most of these are interchangeable with the similarly designated powder, i.e. H4895 with IMR 4895, but this is not always the case. The two 4831s, for example, are quite different and cannot be safely interchanged. For this reason, we recommend that loads be used exactly as they are shown in the manuals with no substitutions. If you have any doubt as to which powder is meant by a particular designation, please call our toll-free technical service line at (800) 223-8799.

The following powders are listed by their approximate burning rate, from “fastest” to “slowest.” It must be clearly understood that burning rates are not linear. There may be several powders which have very nearly the “same” relative quickness listed together, with the next listed powder being significantly different. It should also be understood that the burning rate of any given powder can vary substantially when different cartridges are being compared. Smokeless propellants are organic compounds, and are subject to lot-to-lot variations that are unavoidable during the manufacturing process. As a result, it is quite possible for a “fast” lot of a “slower” burning powder to appear to be somewhat “faster” than a “slow” lot of what would normally be thought of as a faster burning propellant. This situation, in effect, would cause these two powders to switch positions in the following chart. Bear in mind then, that these listings are subject to change depending on the particular lots of powder involved and a host of other variables that become part of the equation. In the following chart, the column on the left lists the powder manufacturer along with their full designation for the powder in question. The center column is the designation used by Sierra in the loading tables of this manual. The right column, where applicable, are some of the designations of this powder as listed in other publications. This is by no means a complete list, and reflects only those powders used in this manual.

Powder/Manufacturer Sierra’s Designation Also Know As, or may
Factory Designation 5th Edition Manual be listed elsewhere as:
Norma R1 Norma R1 R1
Vihtavuori N310 Viht N310
Hodgdon Titewad Titewad
Accurate Arms Nitro 100 AA-N-100 N100
Hercules/Alliant Bullseye Bullseye B’eye
Accurate Arms Solo 1000 Solo 1000
Hodgdon Titegroup Titegroup
Accurate Arms No. 2 AA-No.2 No.2, #2, AA #2
Alliant American Select Am. Select
Hercules/Alliant Red Dot Red Dot RDOT
Hodgdon Clays Clays
Vihtavuori N320 Viht N320 N320
Winchester Super Target WST Win WST
Ramshot Competition Competition
Hodgdon HP38 HP38 HP-38
Winchester 231 231 WW 231, W-W 231, Win 231
Ramshot Zip Zip
IMR Hi-Skor@ 700X 700X 700-X
Hercules/Alliant Green Dot Green Dot GDOT
Hodgdon International Clays Int’l Clays International
Vihtavuori N330 Viht N330 N330
IMR PB PB
Accurate Arms No. 5 AA-No.5 No. 5, #5, AA #5
Winchester Super Lite WSL WSL1, WSL8, Win WSL
Hercules/Alliant Unique Unique UNIQ
Hodgdon Universal Clays Univ. Clays H. Universal

(Universal Clays should not be confused with Hodgdon’s Clays, or International Clays. These three powders are different and should not be interchanged.)

Alliant Power Pistol Power Pistol
IMR SR 7625 SR 7625
Hodgdon HS-6 HS-6 HS6
Ramshot Silhoutte Silhouette
Winchester Action Pistol WAP Win WAP
Vihtavuori N340 Viht N340 N340
Winchester 540 540 WW 540, W-W 540
Hercules/Alliant Herco Herco
Winchester Super Field WSF Win WSF
IMR SR 4756 SR 4756
Vihtavuori 3N37 Viht 3N37 3N37
IMR AHi-Skor@ 800X 800X 800-X
Accurate Arms No. 7 AA-No. 7 No.7, #7, AA #7
Hodgdon Longshot Longshot
Ramshot True Blue True Blue
Vihtavuori N350 Viht N350 N350
Vihtavuori 3N38 Viht 3N38 3N38
Hodgdon HS-7 HS-7 HS7
Hercules/Alliant Blue Dot Blue Dot BDOT
Vihtavouri N105 Super Magnum Viht N105 N105
Accurate Arms No. 9 AA-No.9 No.9, #9, AA #9
Ramshot Enforcer Enforcer
Hercules/Alliant 2400 2400
Vihtavuori N110 Viht N110 N110
Hodgdon Lil’Gun Lil’Gun
Norma R123 Norma R123 R123, R-123
Hodgdon H110 H110 H-110
Winchester 296 296 WW 296, W-W 296, Win 296
IMR SR 4759 SR 4759
Vihtavuori N120 Viht N120 N120
IMR 4227 IMR-4227
Accurate Arms XMR-5744 XMR-5744 5744, AA-5744
Hodgdon H4227 H4227
Vihtavuori N130 Viht N130 N130
Accurate Arms 1680 AA-1680 1680
Norma 200 Norma 200 Norma N-200, N200
Vihtavuori N133 Viht N133 N133
Hodgdon H4198 H4198
IMR 4198 IMR-4198
Accurate Arms XMR-2015 XMR-2015 AA-2015, AA-2015BR
Hercules/Alliant Reloder 7 RE-7 RE7, Re7, RL-7, RX7
IMR 3031 IMR-3031
Hodgdon Benchmark Benchmark
Norma 201 Norma 201 Norma N-201, 201, N201
Hodgdon H322 H322 H-322
Ramshot X-Terminator X-Terminator
Accurate Arms 2230 AA-2230 2230
Winchester 748 748 WW 748, W-W 748, Win 748
Hodgdon Ball C(2) BL-C(2) BL-C2
Accurate Arms 2460 AA-2460 2460
Hodgdon H335 H335 H-335
Ramshot TAC TAC
Hodgdon H4895 H4895 H-4895
Accurate Arms XMR-2495 XMR-2495 2495, 2495BR, #2495, AA-2495
Hercules/Alliant Reloder 12 RE-12 Re12, RL-12, RX12
IMR 4895 IMR-4895
Vihtavuori N135 Viht N135 N135
Hodgdon Varget VARGET
IMR 4064 IMR-4064
Accurate Arms XMR-4064 XMR-4064 AA-4064
Accurate Arms 2520 AA-2520 2520, #2520, AA-2520
IMR 4320 IMR-4320
Norma 202 Norma 202 Norma N202, N-202
Vihtavuori N140 Viht N140 N140
Vihtavuori N540 Viht N540 N540
Accurate Arms 2700 AA-2700 2700, #2700, AA2700
Ramshot BigGame BigGame
Hercules/Alliant Reloder 15 RE-15 Re15, RL-15, RX15
Hodgdon H380 H380 H-380
Winchester 760 760 WW 760, W-W 760, Win 760
Hodgdon H414 H414 H-414
Vihtavuori N150 Viht N150 N150
Vihtavuori N550 Viht N550 N550
Accurate Arms XMR-4350 XMR-4350 AA-4350
IMR 4350 IMR-4350 4350
Hodgdon H4350 H4350 H-4350
Hodgdon H4350 Extreme H4350 EXT
Norma 204 Norma 204 Norma N-204, N-204
Hercules/Alliant Reloder 19 RE-19 Re19, RL-19, RX19
Vihtavuori N160 Viht N160 N160
Vihtavuori N560 Viht N560 N560
IMR 4831 IMR-4831
Accurate Arms XMR-3100 XMR-3100 3100, AA-3100
Winchester Magnum Rifle WMR Win WMR
Hodgdon H4831SC H4831SC
Hodgdon H4831* H4831 H-4831, 4831*
Norma MRP MRP Norma MRP, Magnum Rifle Powder
Hodgdon H450 H450
Accurate Arms MagPro MagPro AA MagPro
Vihtavuori N165 Viht N165 N165
Hercules/Alliant Reloder 22 RE-22 Re22, RL-22, RX22
Winchester WXR WXR
IMR 7828 IMR 7828 7828
Accurate Arms 8700 AA-8700 8700
Hodgdon H1000 H1000 H-1000
Ramshot Magnum (formerly BigBoy) Magnum
Alliant Reloader 25 RE-25
Hodgdon Retumbo Retumbo
Hodgdon H870 H870 H-870
Vihtavuori N170 Viht N170 N170
Vihtavouri 24N41 Viht 24N41 24N41
Hodgdon 50 BMG 50 BMG
Vihtavuori 20N29 Viht 20N29 20N29

*(In manuals or writings published before 1973, any mention of 4831 will refer to Hodgdon’s H4831. In older manuals, it was customary to list the powder simply as A4831” with no designation connecting it to the Hodgdon line. The reason for this is simple; prior to DuPont’s introduction of IMR 4831 in 1972, the surplus 4831 sold by Hodgdon was the only powder to carry this designation. Despite their similar nomenclature, these two powders (IMR 4831 and Hodgdon 4831) are not interchangeable and must not be confused. IMR 4831 is significantly faster burning than H4831, and may produce dangerous pressures if used with data developed for the latter.)