.32 H&R mag sub sonic

[PHATINJUN]

Any thoughts of where to start on a sub sonic load for a rifle? I got some 180 grain 303 bullets to try in the 303 British barrel stubbed on a H&R lug. I had a 300 whisper a while back that I loaded sub sonic but had published loads available . Any good reads out there on sub sonic how to's. Thanks Kurt

[coyotejoe]

Man, that is a tough one, where to start with a 180 grain bullet from a .32 H&R! I don't think you could extrapolate from .300 whisper data. The .300 whisper has quite a bit more capacity than the .32 H&R and many of the listed 300 whisper loads are very hot. Your rifle may have more than plenty of strength but the brass is designed for handgun pressures of not over 20,000 psi. One thing, you won't have to worry about keeping it subsonic, I doubt you could safely load it supersonic.   You might want to try some lighter bullets first, see what you can safely do with a 125-130 grain bullet, then back off the powder charge and step up to a 150 and so work up to the 180s. I'm afraid you are really plowing new ground here and you're pretty much on your own with bullets over 115 grains from that case.

[mcwoodduck]

Would you have over all length problems with the mag case?  The bullet may sit too high in the case and not allow you to chamber with the start of the rifling stopping you.  You may look at the 32 long case to work better for the long 180 grain bullet or possibly throat the barrel or have it chambered in the Ruger 327, that would give you a few more options.
Alliant had a calculator on their web site that let you tell it bullet weight and velocity with a case and it gave you their powder but i have not been there in a long time.  www.reloading.atk.com
Red, green, or blue dot maybe the way to go.
Another place to start for loading data could be with some obsolete cartridges like 32 Win self -loading or 32-30 Remington.  Or current 7.62 Micro -Whisper.or 7.63 Mini Whisper.  
If you do not have a copy of Cartridges of the World it would be a good to get as they have loading data as well.  Both of the whisper rounds above are based on pistol cases and show 180 grain loadings.
One is the 30 luger case the other is the 30 Mauser/tokarev case set up to fire 308 rifle bullets designed by SSK ind.  If you have a contender you may want to just get one in either.  the 7.62 would be easier to make brass as it shares the 9X19 case.
McDuck

[Jerry Lester]

I'd say scrap the 180g idea all together. All you need is 100g to 115g cast bullets, and IMR Trail Boss powder. There's plenty of experimenting room that'll give you sub-sonic velocities. For that matter, you don't even need to use cast bullets. XTP's, or any others in the 100g weight range will work too.

[PHATINJUN]

Jerry after further review I here what your sayin. kurt