.14  Hornet         12
.17  Hornet         14
.17  Rem            27
.204 Ruger          33
.22  Hornet         14
.22  Hornet Impr    16
.218 Bee            18
.22  Rem Jet        18
.221 Rem            21
.222 Rem            27
.223 Rem            31
.222 Rem Mag        32
 5.6x50R            34
.219 Zipper         34
.225 Win            41
.22-250 Rem         43
.220 Swift          48
.223 WSSM           53
.22-06              65
.22-15 Stevens      17
.22 Sav             35
 6x47               33
 6x52R Bret.        36
 6 BR               39
 6x70R              39
.243 Win            54
.243 WSSM           54
 6 Rem              55
.240 Wea Mag        65
 6 USN              51
 6x62R              67
.240 Fl. N.E.       58
.25-20 WCF          19
.256 Win            22
.25-21 Stevens      25
.25-25 Stevens      29
.25-36 Marlin       37
.25-35 WCF          37
.25  Rem            42
.250 Sav            46
.257 Roberts        56
.25-06 Rem          66
.257 Wea Mag        84
 6.5x70R            39
 6.5 Jap.           48
 6.5x52 Carcano     49
 6.5x53R            49
 6.5x54 M-S(.256)   50
.260 Rem            53
 6.5x55             57
 6.5x57(R)          58
 6.5 Rem Mag        68
.264 Win Mag        82
.270 REN            16
.270 Win            68
.270 Wea            83
.28-30 Stevens      37
 7-30 Waters        45
 7x72R              54
 7-08 Rem           56
 7x57(R) Mauser     59
.284 Win            66
.280 Rem            67
 7x65R              68
 7 WSM              81
 7 Rem Mag          84
.30 Carbine         21
.300 Whisper        24
.30-357 AeT         25
.30 Rem AR          44
.30-30              45
.30 Rem             46
.303 Sav            48
.300 Sav            52
.307 Win            54
 7.62 NATO          54
.308 Win            56
.30 Fl.NE Purdey    58
.30-40 U.S.         58
.30-06 U.S.         69
.300 H&H            86
.30 Newton          88
.300 Win Mag        89
.30  Fl. H&H        90
.300 Wea Mag        99
.30-378            130
 7.62x54R           64
.303 Brit           57
.375/303 W-R        62
.32-20 WCF          22
 7.65 Mauser        58
 8x72R              59
.32-40 Ballard      41
 8x50R Lebel        66
 8x57(R) Mauser     62
 8-06               70
 8 Rem Mag          98
.318 W-R            69
.333 Jeffery        86
.33  WCF            63
.338-06             70
.338 Win Mag        86
.340 Wea Mag        98
.338-378           132
.348 Win            75
 9x57(R) Mauser     62
.357 Mag            27
.357 Max            34
.357/44 B&D         35
.400/350 Rigby      78
.350 ME Guide 2     49
.35  Rem            51
.356 Win            57
.358 Win            57
.35  WCF            69
.35  Whelen         71
.35  Greevy         72
.350 Rem Mag        73
.358 Norma Mag      88
.358 STA           105
 9.3x57 Mauser      64
 9.3x54R Finn.      65
 9.3x72R            67
 9.3x62             77
 9.3x74R            82
.360 No.2 NE       111
.375 Win            49
.38-56 Win          62
.375 2½ N.E.        67
.375-06             73
.375 H&H            95
.375 Fl. Mag        97
.375 Ruger         100
.369 N.E.          102
.378 Wea Mag       136
.38-55 Ballard      52
.38-72 Win          74
.38-40 WCF          39
.400 Whelen         75
.405 Win            78
.400 Jeffery       117
.450/400 NE 3¼     123
.416 Taylor         92
.416 Rem Mag       107
.416 Rigby         130
.416 Wea Mag       134
.423 OKH            77
.404 Jeffery       113
.44-40 WCF          40
.44  Spl            34
.44  Rem Mag        39
.444 Marlin         69
.45  Colt           42
.454 Casull         47
.45-70 U.S.         79
.450 Marlin         74
.450 Alaskan        88
.45-90 2.4"         90
.458 Win Mag        94
.458 Lott          108
.450 3¼ N.E.       129
.460 Wea Mag       140
.465 N.E.          144
.470 N.E.          146
.475 3¼ N.E.       137
.50-110            109
.50 BMG            293

Cartridge Case Capacities

Given are approximate case capacities, in grains of water to fill the case to the mouth. The values are averages of several sources. References include Handloading, by W.C. Davis (NRA, 1981) and the internal ballistics programs QuickLOAD, LoadTech, and Load-from-a-Disk. Measurements from fired cases found at local ranges were used when available. Estimations (see below) based on the capacity of a parent case were also made. The listing is arranged by bullet diameter and then by volume.

My thanks to those who've sent case measurements by e-mail. Special thanks goto Ed Reynolds, the author of LoadTech and AccuLoad, who gave me a copy of the extensive list of case measurements he's made over the years.


When measuring the water capacity (volume) of a case, it's better to use a fired case before it is resized, since this is closer to the size of the case expanded at firing. A little dishwashing soap lets the water lie flat across the case mouth, improving the accuracy of the measurement. I find it simplest to first weigh the dry case, fill it with water, and then dump the water and case into the scale's pan.

Cases can vary greatly in weight among makers. In general, modern cases are slightly thicker and heavier than older ones for the same cartridge. Heavier cases will have less capacity, with every 8.5 gn of brass displacing about 1 gn of water capacity. In small cases such as the .22 Hornet, differences of up to 10% can be found, but variations of 2 gn of water is more typical for cases of the size of the .30 Springfield.


Other values include my estimates based on either the weight of sample brass or on the capacity of the parent brass. I used a technique suggested by Ken Howell in his book Designing and Forming Custom Cartridges. One starts with either the maximum dimensions of the outside of the case or the minimum dimensions of the chamber, as given by the relevant standard, such as SAAMI or CIP. (The maximum dimensions for the case body will better approximate the chamber.) One then computes the weight of water to fill this volume. The weight of the brass is divided by its specific gravity to give the weight of water it displaces, and this is subtracted, leaving the internal case volume.

This approach allows one to estimate case volume if you don't have on hand a fired case to fill with water. For example, if you use the weight of .45-70 brass along with the outer dimensions of the .33 WCF, you will get a good estimate of the latter's case volume. The estimate is improved if you use actual measurements from the rim, which does not expand on firing.

When using this approach, I've found the estimated volume is usually higher than published values by a grain or two. I can think of three reasons. First, the calculations assume a sharp cornered shoulder whereas most cases are slightly rounded. Second, neither grooves in front of the rim nor bevels on the rim are considered. Third, when filling a fired case with water, I suspect little water gets into the primer pocket. The volume of a large rifle primer pocket is about 1.1 gn, and that for the small rifle primer is about 0.7 gn.

Howell recommends using a specific gravity of 8.56, assuming the brass is 70:30 in composition. In the April, 1978 American Rifleman, Davis lists 8.44. I use the average of these, or 8.50.

If you wish to play with this technique, a calculator is given below (Javascript must be enabled for it to run). All dimensions are inches or grains, and the lengths are to be measured from the base of the cartridge. The calculator assumes a rimmed cartridge. If you have a rimless cartridge, enter for the rim the inner diameter and the average width of the extractor groove. A correction is made for the primer pocket.

If you have only the case's capacity and dimensions, you can enter the capacity after the dimensions and receive an estimate of the weight of the brass. You can then neck down or blow out a case of this weight to find the approximate capacity of the custom case you have in mind.

Using this data and calculator along with a Powley Computer, one can estimate the performance of most custom cartridges. This calculator should estimate case capacity to better than 4%, and given that a 4% change in case capacity gives about a 1% change in velocity, that is usually close enough.

diameters lengths

SAAMI dimensions call for a straight taper case with no particular neck. This calculator assumes a neck, so one is faked by entering a "shoulder" diameter equal to the neck diameter and located right at the case mouth. The dimensions used for the rim are between the SAAMI minimums and maximums, while in the case body, the SAAMI maximums were used, to better approximate the fired case. The weight of the brass is from one sample. The case capacity for this cartridge is usually reported to be 79 gn.

This case is formed by necking down .45-70 brass, in several steps. This example uses the numbers from the .45-70 example but with the smaller shoulder and neck of the new case. The volume for this cartridge is usually reported to be a bit under 63 gn.


I have not tested QuickDESIGN, but it should allow you to make quite accurate estimates of case volume. In addition to setting the outside dimensions of the case, you can enter extractor grooves, radiuses at corners, etc., and it will assist in selecting the thickness of the brass for the walls and the web. Also offered is the excellent internal ballistics simulator QuickLOAD which has a large list of case capacities.

The internal ballistics software Load From a Disk advertises their "cartridge case database includes over 650 standard cases with dimensions and case capacity values." I have not tried the current release of this software. RCBS.LOAD from RCBS has "a database of dimensioned drawings for over 496 cartridges," but I have not tested it either. AEM offers two software reloading tools, and their AccuLoad is advertised as having a case capacity calculator and a database with "over 2000 cartridges." I have not tested the current release, but the case capacities in their original LoadTech software were generally higher than most sources report.

From Germany, the reamer maker Triebel offers cartridge and chamber dimensions in their Pa.u.la software, on CD. While likely in German, getting the numbers you need from it should not be difficult. With over 900 cartridges cataloged, any obscure European (or American) cartridge is likely covered.


There are several good references for cartridge dimensions and conversions. Most are available from Huntington's and Buffalo Arms or from book sellers including Ray Riling and Mike Stegan.

Howell's book is the best single reference on the subject. There are hundreds of cartridges, and he included only cartridges for which he had a reliable source for dimensions, such as SAAMI, CIP, RCBS, Triebel, old manufacturer's catalogs (Winchester, Kynoch, etc.), and other original drawings. So far, I've found only a few typos in the drawings. His suggestions for case re-forming operations (annealing, etc.) all seem safer than some of the those I've read elsewhere. While many drawings include recommendations for which case to use to form another, a few of these aren't too promising.

The CIP standards for current cartridges at times can be found on their site.

The Birmingham Proof House in the U.K. offers the CIP standards on CD. They will also search their archives for information on older cartridges and will provide you with photocopies. For the older British cartridges, this is surely the best source for information.

The Home Guide to Cartridge Conversions by George Nonte is decent but a bit dated. Some of the listed conversions seem pretty iffy, but he has some re-forming techniques not mentioned by Howell. If you can buy a used copy for a good price, try it.

The Handloader's Manual of Cartridge Conversions by John Donnelly had too many obvious errors for me to bother keeping it, and I gave my copy away to a friend who was interested in it. If you can borrow a copy, there's a number of good points in it. The new 3rd edition has been revised by another author (Donnelly died a while back), so perhaps my complaints are no longer applicable.

Ackley's two volume Handbook for Shooters and Reloaders has some information on case capacity and forming operations. It is notorious for very hot reloading data.

For the cost of the postage, I gave away the two volume set Wildcat Cartridges from Wolfe. Howell's book has many of the more interesting cartridges from these; indeed, Howell was editor of Handloader magazine when some of those articles were orginally published there. Unlike Howell's book, these old articles have loads and fps figures, but I found those numbers could be as unreliable as Ackley's. Howell's book plus QuickLOAD for loads is a much better bet.

The reamer maker JGS sells books of chamber prints, as does Pacific Tool & Gauge. You might also be able to get chamber prints from CH-4D, who offers an extensive line of reloading dies.


I'd be grateful for measurements of case capacity and case weight for any cartridge, but especially the older, unusual cases. These measurements will be used to improve and expand the listing here. My current e-mail address is kept on this site's home page.