Anybody Heard of X-283?

[fourarmed]

A shooting friend has quite a bit of a flattened ball powder called X-283. The kernel size is a little bigger than most that I have seen. One container he has is marked (felt marker on duct tape) "4831 Data." He is hesitant to rely on that.

Does anybody know anything about this powder? Some of it is packed in 1lb. sacks, and some of it is packed in bulk. It is possible that it came from Lake City sometime in the past.

[madsenshooter]

on google I found mention of it being used in the 6.5X300 Wright-Hoyer Weatherby. But I tried following the link only to come up with nothing. With a designation like that, I'm going to guess it may have been an experimental govt surplus powder. If there's any credence to the 4831 data scrawling, it'd be like H450.

[fourarmed]

Thanks for that tip. I looked in Ackley's manual and found data supplied by Hoyer that indicates that 283 may actually be a little slower than H870. It must have been a .50 BMG powder.

[BerdanIII]

There is a comparison chart in one of the old Handloader's Digests; I'll post the data tomorrow. If I remember correctly, it was an experimental powder and Hodgdon had very little of it ("little" might mean a couple of tons). Burn rate was right in with other surplus .50 caliber powders.

Found it.

From: Here's How to Pick Powders, Robert Hutton, Handloader's Digest, 4th Ed. (1968)

These powders were grouped together in burning order in a table in the article:

IMR 5010 "slowest burning DuPont, was used as a machine gun powder during WWII, would be highly useful in the largest wildcat cartridges."
H5010 "Discontinued by Hodgdon, it is available to the major reloading companies from DuPont."
X283 "an experimental powder during WWII, and Hodgdon reports only 3000 lbs. left."
H202 "also experimental, is no longer available"

From: Hodgdon Smokeless Powder ad, Handloader's Digest, 2nd, Ed. (1964)

"5010 (M.G.) - the slowest powder adaptable to sporting arms. Only in large cases with extremely heavy bullets can pressure be brought up to give good velocity. 1 lb. can, $1.50."

From: Handbook for Shooters and Reloaders, P.O. Ackley (1962)

General Information - Surplus Powders, by B.F. Hodgdon
Reduce first test load by 5% from highest shown.

Loading Data for 5010 - 50 MG

Caliber - Bullet Weight - Powder Charge - Velocity
6mm - 105 gr. - 80.0 gr. - 3719 fps
6mm Improved - 90 - 86.5 - 3542
6mm Improved - 105 - 86.0 - 3552
.270 WCF - 150 - 66.0 - 2772
.270 WCF - 170 - 66.0 - 2670
7mm/06 - 175 - 62.0 - 2195
.30-06 - 150 - 60.0 - 2251
.30-06 - 175 lead - 56.0 - 1992 (Lyman 311467; duplicate load in Lyman manual)
.30-06 - 180 - 60.0 - 2171
.30-06 - 200 lead - 56.0 - 1910 (Lyman 311284; duplicate load in Lyman manual)
.30-06 - 220 - 60.0 - 2137
.300 Weatherby - 220 - 94.0 - 2603

From: Speer #6 (1964), H5010 data

.300 Weatherby - Rem. cases, Rem. 9 ½ primer
180-gr. Speer 3085-180-6-SP - 92.0 to 98.0 grs - 2847 to 3059 fps
200-gr. Speer 3085-200-6-SP - 89.0 to 95.0 - 2797 to 3010

It seems like the burn rate is closer to 5010. Either way, it looks like you'll be using a coffee cup as a powder scoop.

[fourarmed]

Thanks very much, BerdanIII. That will be quite helpful.

[45nut]

I am again,, in awe of the knowledge available here. Pretty rare to stump this group!

[deerslayer]

I am again,, in awe of the knowledge available here. Pretty rare to stump this group!

Ditto, thanks for all the data you got me Berdan

[BerdanIII]

You're welcome.

Just paying forward for all the help and information (and laughs) that I have gotten from this site.

[StarMetal]

Some of that load data looks off. For example the 6mm Rem with a 105 grain bullet with 80 grains of 5010 giving 3719 fps...no way no how. Why would the improved version with more powder get much much less velocity?

[BerdanIII]

I'll go back and look at the source material, but I'm reasonably sure that what I posted is in the book. I think Ackley and his friends got a little optimistic on the velocities they were getting (trying to match steel penetration to velocity seems inexact to me). On the other hand, they were using barrels up to 30" long.

Edit:

The data I posted is the same as what's in the book. It may be a typo in the original manuscript: 3179 fps might be the actual number. Also, not all of Ackley's "improvements" really were.