All, As you may remember, I've been testing IMR 7383 in various rifles with different types & weights of bullets just to determine what it's good for. Today I tried it in my '06 with 125gr. Sierra SP's v. IMR 4350 with the same bullet. The powder charge was 55gr., the primer was WLR (mag. primers aren't needed), the OAL was 3.23" and the brass was evenly divided bet. Rem. & Win. The results are below:

Powder Brass Mean SD ES n
4350 Win. 2,545 23 64 5
7383 Win. 2,689 19 58 11
7383 Rem. 2,706 23 87 11

Obviously the data is in fps, but note that the difference bet. Rem. & Win. brass is not statistically significant (T-test).

Accuracy was excellent, i.e., 5 shots & 7 shots in 1" or less @ 100 yds.; no pressure signs at all; and only a wee amount of fouling on the necks. Funny thing, the Lyman "book value" for 55gr. IMR 4350 wasn't reached by my lot of 4350, but was fairly close for the milsurp powder. Hope this helps. ...Maven

Sorry about the data compression in the table above. I didn't realize this format had such "issues." ...Maven

Maven,

I have read different burning rates for this powder--anywhere from 4064 to 4350. It would appear your lot is the 4350 burn rate. I wonder if this powder would have similar burning rate in a 270 or even possibly a 30-30? I am going to get a jug sometime in the future, so I have been reading all I can about it. I sure like those slow burning surpluses (WC-852, WC-860, and yea 5010PD)in the 30-30!!! They ain't too clean burning--852 ain't bad though--but accuracy is pretty darn good from a couple of 94's. Velocity from the two slowest burners is sad, but they still hit the target! Thanks for the info on the 7383...BCB

BCB, You're welcome! I've also tried 7383 in the .243Win. with 85 & 87gr. jacketed bullets, treated it as 4350 and lived to tell about it. Actually, not much to say except 42gr. was all I'd use in that cartridge in a strong rifle. Thus, I'd assume you could try 7383 at the starting charge for 4350 as per your favorite reloading manual, but be careful as it gives pressure signs with heavier bullets. ...Maven

Thanks for the data, Maven! It came through quite readably here.

I've successfully used 7383 in the .243, 6.5x55, .257 Roberts, and the .270.With the lighter bullets so far I could not get enough powder in any of these cases to come close to what looks like high pressure. ( no compressed loads but close.) All loads displayed reasonable accuracy. Density is a good bit lower than any of the 4350s. This week I'm trying it out in the 22-250 and the .358X .404. will fill you in. Roger

Did the 7383 in the 22-250 with 4 different bullets; same powder charge 33.5gr.There was just a little stickyness in bolt handle lift but the primers and cases really looked great.
The best 5 shot group was 3/4" with Speers 52gr.HPBT,WLR primers and win. cases.The powder was starting to fill the neck.
In the .358X.404 IMP.
1. 200gr. sprnw/c ( Bargin brand ?) 82.5gr. 7383 CCI Mag. primer Norma cases, not hot 5 shot 2" group.
2. 180gr.PSP (bargin brand ?)85.5gr 7383, CCI Mag primer, Bell case. mild, 2" group.
Now the good news is this rifle never shot any better than 2" groups. OK! So I use cheap bullets.
After using this powder in 6 different rifles I am impressed. My Chrony let me down, I can tell I'm not maxed out,and the velocities are not fantastic. But it shoots good and the only case that probably could have been able to be overloaded to any extent was the .358x.404.