IMR 7383 Powder Question

[TCLouis]

Dang, meant to put this in the powder section.

Hopefully the moderator will do so.

There are apparently three lots out there.

Mine is 48001

What are the lot numbers and which is fastest, slowest (other one has to be in between then)

I have read it is sensitive as it gets up close to max loading.

In something like 06, is spike caused with 0.5 grain additional powder, 1 grain, or more.

My lot is from Jeff Bartlett said use 4831 data minus some percent. Whatever percent reduction that was, when I calculated it for every cartridge I was interested in, it came out to compare to 4064.

Have others found this to be true?

[Yodogsandman]

This is the best info out there that I know of....

http://www.castpics.net/LoadData/7383/default.html

[freebullet]

Like 4064 in smaller rifle cases in charge weight not velocity. More like 4831 or 4350 in larger cases with 15% by weight reduction in charge. Iirc 85-105% case fill is g2g in most calibers under 308. I wouldn't be looking for maximums with this powder. We're I looking to go over 95% fill I would only go .1-.2 grains at a time, call me over cautious but I enjoy shooting and don't want to blow up guns. In cases like 223 you almost can't overfill them, however if you settle the powder you could potentially over compress it. Go to cast pics they have downloadable data pages from a couple members here in several calibers.

[MT Gianni]

No, I stuck a bolt with a 35 W using 4064 data.

[Maven]

TCL, My current jug of IMR 7383 has NO lot number on its label, but it burns identically to the previous 7 lbs. I had whose lot no. I didn't record, although I may have mentioned it in a post years ago. To the point, I started loading 7383 for the .30-06 and .243Win. with jacketed bullets using IMR 4064 data, but found it to be much too slow. I then tried starting loads for IMR 4350, which I got from Lyman's "Reloading Handbook, 47th Edition" and got both the velocity and accuracy I was looking for without any pressure spikes, unburned powder or other problems. In those 2 cartridges, IMR 7383 is actually a bit slower than 4350 and quite a bit fluffier, i.e., a given charge occupies more of the case than 4350. Lastly, I found it to be sensitive to ambient temperatures and thus use 1 gr. - 1.5 gr. less in my .243Win. in warmer weather than I normally do. E.g., 40.5 gr. 7383 + 85 gr. or 87 gr. Hornady or Sierra SP's or HPBT's + Win. LR primers -> ~3k fps, which is all I need for accurate paper punching. It is also my MAX. load.

[swheeler]

Lots are RAD-78L,DUW 48001, DUW 48000