reloading advice for subsonic 38spl

[rc51kid]

I have 357 Handi with a 16" barrel that i use with a Octane 9 suppressor. I have only shot my hand loads through it. I was using 158gr LSWC, winchester pistol primers, and 5.0 gr unique. These sit right between normal and +p loads. In my 4" 686 I THINK they were about 890fps but the chrono was a little to close to the muzzle. I had shot a few of them through the Handi suppress and they are stupid quiet. But then today  i shot one expecting the SUPER quiet little pop and i got a sonic crack, sounds like a 22lr report. I was shooting in a area that i really should not be shooting. So this was not a welcome thing. 

I guess i didnt think that the extra barrel lenght would push that round supper sonic but i guess it did. So what are some good recomendations for subsonic 38spl loads from a 16" barrel?

I know i could back down on the powder for my 158gr bullets. What do you think would be a good amount? 4.5gr Unique? I also just ordered some 180gr LRN bullets to try. Any ideas on how much unique to use to push those around 1000fps?

[SHOOTALL]

3.9 grains of unique will 750 fps from a 4 inch bbl. the max load in hornadys manual 14th edition is 4.4 gr of unique in a 38 spl., you are in 357 mag levels. 5.1 gr of unique should give yo 900 fps in the 4 inch bbl. so reducing to 38 spl. loads you might stay under 1050 fps in the 16 inch bbl. You might try a 200 gr lead bullet .

[rc51kid]

3.9 grains of unique will 750 fps from a 4 inch bbl. the max load in hornadys manual 14th edition is 4.4 gr of unique in a 38 spl., you are in 357 mag levels. 5.1 gr of unique should give yo 900 fps in the 4 inch bbl. so reducing to 38 spl. loads you might stay under 1050 fps in the 16 inch bbl. You might try a 200 gr lead bullet .

Thanks for your info. I am still kind of new to the reloading. So i am open to all advice. I looked on the Alliant web page and got load data for Unique. They say 4.7gr for 38spl and 5.1gr for 38spl+p. I mostly shoot these out of my 686 so i figured a "light +p" should be fine. I guess i could should chrono a few out of the 16" barrel first, then drop them down to 4.5gr or so.

[geezer56]

No experience with a can, but I have played a bunch with popgun loads.  Always use cast bullets, a stuck jacketed bullet is NO fun.  Ambient temperate can really change the sound signature of a particular load.  If it's right on the edge of sonic, it can creep over sonic with a few degrees change. 

[Dinny]

I agree with the others who mentioned using a 200gr bullet and about shooting lead. I have shot 2 gr of BE under a 200gr cast bullet in 38 Spec brass from my Maxi chambered 22" barrel. Nothing wrong with BE, but I only use TB powder now though.

Thanks, Dinny

[rc51kid]

i chronoed one of the rounds today and it was 1018. I it was not far from going supersonic. I guess i will back off to 4.5gr Unique for these loads.

[Lonegun1894]

I have gone down as low as 2.7 grs Unique in my Rossi 92 rifle.  Do yourself a HUGE favor and do your load testing WITHOUT the suppressor on to make sure your bullets are staying stable on paper.  If you goof this up and get one that goes unstable immediately after leaving the muzzle, you could get a baffle strike and damage your can.  Since you have the capability to chrono your loads, there is no use in risking your investment, as your bullets will eventually go unstable, which you can tell when they quit cutting clean holes in paper.  Not trying to be a jerk, so I hope I haven't crossed the line, but having gone through the NFA wait myself and having a friend who learned this lesson the same way you may if your luck runs out, I thought I'd try to warn you of a possible problem with this testing.  If your bullets cut clean holes with a subsonic load unsuppressed, they will do the same once you attach your can also, but at least you'll know without taking a risk.  BTW, this is a great thread as I have been seriously trying to decide if my next can will be .30, .35, or .45.

[gcrank1]

Looking back at some old data with some 38Spl. loads chrono'ed from revolver and carbine it seems that the carbine gained about 400-450fps over the revolver (forget the barrel length, but 4 or 6 1/2" Im pretty sure. These may have been with 2400 rather than Unique, but it might give you an idea of the velo increase one gets going to a carbine to adjust your load.

[LaOtto222]

I have been using a 148 grain hollow base wadcutter over 3.0 grains of Bullseye in 38 Special cases. It runs right around 900 fps out of a 22" barrel. It is subsonic. I can shoot it in the middle of the night and not wake up my wife, even in the Summer with the windows open, without a can. I dispatched a Raccoon and a Skunk and I was not more than 20 feet away from the bedroom with the back door open.

Good Luck and Good Shooting

[nanuk-O-dah-Nort]

I'm lucky that way

I can touch off a factory 270Win in the driveway, and my wife in the living room won't hear it!

I sometimes wonder if she is deaf....