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View Full Version : .38 specail OAL 1.40 inch 975fps



10mmShooter
08-08-2010, 04:57 PM
Hi Guys,

Just need to see if anyone is using a load close to this.

weapon is a SW686 8-3/8 barrel(.357)
powder charge is 4.8g WW231 (max .38 +P loading per Winchester manual)
OAL is 1.40 in with bullet seated to top of the crimp grove(.38 brass)
bullet is a 150 SWC RCBS, avg weight 153g
Federal small mag primer #200
minimal crimp just enough to knock the bell off the case.

Winchester manual says 860 fps...assuming more normal OAL of 1.455

My goal is to deep seat to gain better inigition and consistency in fps.

Currently my chrono is showing my load at average 975fps over thirty rounds. Obiviously I'm running higher pressure given the deeper seating of the swc(about 40 thousandths). I seem to have picked up 110 fps. Which is good and what I desired, extreme spread is small now. Also no hard extrations, no smushed primers...everything looks good.

Just want to confir to see if anyone has a similiar loading and what velocities are you seeing?? :coffeecom



http://www.keithrussell.net/seatingdepth.jpg

Ben
08-08-2010, 05:08 PM
4.8 grs. of what ?

10mmShooter
08-08-2010, 05:23 PM
Ww231

Shiloh
08-09-2010, 06:24 AM
Nice Boolits!! Wheel weights??

You are experiencing ignition problems with WW 231??

Shilho

10mmShooter
08-09-2010, 06:41 PM
Shiloh,

No ingition problems...just want to try to shrik my exterme spread to <50 fps.

Cherokee
08-09-2010, 07:09 PM
You don't need the mag primers with 231 but they do work. I use a similar load with Lyman 358477 @ 3.3 gr , flush seated like yours at 1.385" and CCI SP primers. Chron @ 805 fps from 6" Colt revolver. Have also used 5.0 gr 231 with same components @ 1.463" OAL but never run it over the chron. Gave good accuracy in Diamondback 6". If you have trouble getting 231, try WST which is also very good for me.

AZ-Stew
08-09-2010, 08:35 PM
In the three cartridges on the left, I see either three different seating depths or three different case lengths. The round on the far left appears to have it's front driving band inside the case mouth on the left, and outside on the right (the case mouth is not square). The middle cartridge has significant protrusion of the front driving band all around. The right hand cartridge in the left group of three has less protrusion than the one in the middle. If this is a seating depth problem, look to your die setup and make sure all die parts are locked into place. What is more likely, though, is that the cases are not all trimmed to the same length. If this is the situation, you'll never reduce your shot-to-shot variation. I'd start by trimming the cases. If they're all the same length, they can be crimped to almost any degree and you will get consistent results within the batch.

P.S. You might also want to try a bulkier powder, rather than seating the boolits deeper into the cases. At a certain depth, the case walls taper inward. As you seat the boolits deeper, two things may happen: 1.) The lower part of the case may bulge at the boolit base. 2.) The boolit base will be "sized" smaller by the taper of the inner case wall.

Regards,

Stew

10mmShooter
08-09-2010, 09:02 PM
AZ your observations are accurate the brass is mixed. I guess in my quest I need to sort the brass by head stamp and trim it to a uniform lenght. I've been resisting the need to trim pistol brass but I"m willing to give it a try.

to the bulky powder bit.....I have some Red Dot, which is a very fast powder and more bulky that 231. I may load a few up, I may have to run at 4.2 grains cause I really what my 150 SWC to run about 925-950 fps.( got an old Hornady manaul showing max charge of Red Dot in .38 brass to be 4.2)

I have really tried to stick with WW231 because it really supposed to be a great .38 powder and very accurate.