Thread: Accurate subsonic .357?

Hello guys, I just bought a Marlin .357 and put a DPT suppressor on it.

All my shooting is plinking at the range so the key is accuracy.

I also bought a Lee 358-150-1R mould and cast off a quick batch of projectiles and loaded them with 4gr of AP70N (50 total). I wouldn't consider the grouping to be that great though there were gusty cross winds and an 8 pound trigger which has now been fixed to 3 pounds. They grouped anywhere from 8-10MOA (4-5" @ 50m). There wasn't any load data for this weight projectile so I interpolated start loads for 140gr and 158gr cast anticipating around 900FPS. I also shot my supersonics and got 3.5" @ 100m so I know I can pull these numbers in on a more favourable day with better trigger now.

I was wondering firstly if anyone has had luck with this 150gr projectile in subsonic loads (what powder/load) and secondly, what other success have you had with ANY .357 subsonic loads (projectile weight/powder/load)? I'd consider a commercial bullet or purchasing another mould if I can find one.

My carbine only has a 16.25" barrel 1-16 twist. Yes I fully understand what worked for you may not work for me. Just looking for ideas.

I'll load up 10 of each with these loads 3.6, 3.8, 4.0, 4.2, 4.4, 4.6. Hoping to pull that group into 1.3" @ 50m or 3MOA.

I know it's not what you are asking exactly but we use the sellers and belliot(?) Factory 38 special rounds in our Marlin 357 , the stainless version of yours, and that shoots around an inch at 50 if that's any help at all. Maybe you could research that projectile etc.

Originally Posted by Ftx325

I know it's not what you are asking exactly but we use the sellers and belliot(?) Factory 38 special rounds in our Marlin 357 , the stainless version of yours, and that shoots around an inch at 50 if that's any help at all. Maybe you could research that projectile etc.

Thanks Ftx325, yes all info like that helps. Nice rifle you have there too. I would have got one if I found one in .357mag. Apparently a very popular cal.

@Coote has whole thread on this somewhere.

Try a faster burning powder AP70 in my 6" barrelled pistol with a 135 grn cast HP shoots best at 7.3 grains
For lighter loads I use 700X powders like AS30 AS50 WW231 Red dot are in the same burn range will keep the pressure up
Look for a mould for the 173 grain 357429 Lyman it is the original bullet used to develop the .357 Mag back in 1935
I have a one and can sell you some projectiles if you like.

One thing that made my subs more consistent and accurate was crimping

Originally Posted by Ftx325

I know it's not what you are asking exactly but we use the sellers and belliot(?) Factory 38 special rounds in our Marlin 357 , the stainless version of yours, and that shoots around an inch at 50 if that's any help at all. Maybe you could research that projectile etc.

for accuracy you cannot go past the old Bullseye &148gn wadcutter load however not that easy to load in a rifle - only via single shot feedsi find the most accurate load in my 357 CSBL to be the max load of Win 296, a magnum primer and 158gn plated projectiles

Originally Posted by shooternz

Try a faster burning powder AP70 in my 6" barrelled pistol with a 135 grn cast HP shoots best at 7.3 grains
For lighter loads I use 700X powders like AS30 AS50 WW231 Red dot are in the same burn range will keep the pressure up
Look for a mould for the 173 grain 357429 Lyman it is the original bullet used to develop the .357 Mag back in 1935
I have a one and can sell you some projectiles if you like.

Thanks shooternz. I've tried but yet to shoot a incremental loads as mentioned above with the AP70 but have also created a small ladder of APS450. That'll be interesting to try as well. I love the sound of trying your 173gr. I think that would be a perfect weight and a practical bullet for this 1-16 barrel.

I'd definitely like to purchase some from you to test out a heavier bullet. I'll PM you.

Originally Posted by Bill999

One thing that made my subs more consistent and accurate was crimping

Hi Bill999, yes I read about various crimps. These will be low recoiling ammo so I guess a lighter crimp might be the way to go? What worked for you and what sort of results were you achieving?

Originally Posted by omark

for accuracy you cannot go past the old Bullseye &148gn wadcutter load however not that easy to load in a rifle - only via single shot feedsi find the most accurate load in my 357 CSBL to be the max load of Win 296, a magnum primer and 158gn plated projectiles

Thanks omark, I'll try these as a supersonic load. How do you find leading? A full 296 load would have them steaming!