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View Full Version : 243 Winchester and IMR 7383



johnly
06-20-2021, 03:23 PM
Years ago I purchased a case of IMR 7383 for shooting cast bullets, but as it turns out it works quite nice in a 243 with ~70 grain bullets.
The back story is that I was looking for a simple light bullet load for my sporter weight 243 that didn't generate maximum pressures or velocity. To this end, I tried modest charges of RL-7, AA2200, AA2460, and H322 behind a selection of 68-70 gr. bullets I had on hand and powders (I had an abundance of). The RL-7 load delivered a nice 3/4" 5 shot group, which isn't unusual as the rifle will sometime deliver nickel sized groups. In a previous post I asked about using IMR 7383 in my 43 Mauser, which turns not to be a good idea in the weak 71/84 action. But during my internet searches I came across a post recommending 41.5 gr. of IMR 7383 in the 243 with 68 grain bullets as it delivered ~3000 fps and solid accuracy. So I decided to give it a try, using the Speer 70 HP, and some other custom benchrest bullets I had on hand. The Speer bullets punched a couple 5/8" groups and two of the groups using benchrest bullets were in the 1/2" range. Needless to say I was pleased with the results. Might just have to try IMR 7383 in my 25-06 with light bullets to see if similar results are obtained.

Just passing along this information for others to leverage.

Maven
06-20-2021, 04:28 PM
I've used it for years in my .243 Win., but with 85 - 87 gr. spire points: Excellent accuracy and speed.