The Accurate Reloading Forums
.358 Winchester sub-caliber insert
22 March 2025, 19:32
Rick R.358 Winchester sub-caliber insert
I’ve searched online without success, does anyone know of a source for a chamber insert to fire .38/.357 in a .358 Winchester?
I have a TC Encore with a 20” aftermarket .358 barrel that’s pleasantly accurate but loud and kicks like a mule with full tilt ammo.
My next plan is loading some pistol bullets with 2400 in .358 cases but the ability to simply drop in a .357 Magnum load would be nice.
22 March 2025, 19:52
jeffeossoi would recommend trailboss rather than 2400 - follow their recipe for developing loads - i also suggest not going lighter than 150 gr bullets
in the end, way more cheap than a custom insert or replacement barrel
22 March 2025, 21:49
Rick Rjeffeosso,
I have about 20# of 2400 and no Trailboss plus some load data for 2400 with a 200gr cast bullet. I figure 158gr or 180gr pistol bullets might hit in the same Zip code as the 180gr Speers it’s sighted in with presently.
I’ll be on the lookout for Trailboss at the local fun stores.
22 March 2025, 23:06
jeffeossosweet -- i like 2400 in my 45colt hot loads!
It would be easy to make the inserts; I have made them for other calibers.
23 March 2025, 04:39
Hipshoot10gr. Unique with a 158gr. SWC GC.
Hip
23 March 2025, 04:50
Rick Rquote:
Originally posted by dpcd:
It would be easy to make the inserts; I have made them for other calibers.
It looks pretty straight forward to me, which makes me curious as to why I can’t find anyone making them.
quote:
Originally posted by Hipshoot:
10gr. Unique with a 158gr. SWC GC.
Hip
10gr or so of Unique is my second choice since I have a few pounds of that too. I’ve used both 2400 and Unique in bottleneck cases in the past.
23 March 2025, 07:34
Lamar2400 will do everything you need done.
and at half the price of lightning no-2,, err trail boss.
if you wanna match 357 mag velocities, stuff like titegroup and red-dot will work like a champion.
23 March 2025, 18:31
Rick Rquote:
I had heard MCA was out of business and the last post on their Facebook page was from 2020. I just sent them an email, interested to see if there is any response.
quote:
Originally posted by Lamar:
2400 will do everything you need done.
and at half the price of lightning no-2,, err trail boss.
if you wanna match 357 mag velocities, stuff like titegroup and red-dot will work like a champion.
If I had any red-dot my father in law would confiscate it for target 12ga loads. Clays might be another option and I do have a small amount of it.
23 March 2025, 21:56
p dog shooterAfter playing with sub caliber stuff.
I decided it is just easier to buy another rifle in the smaller caliber.
This article will help you with ideas for a load for your 358.
https://leverguns.com/articles/paco/small_charges.htmNo one makes them because there is no demand. Ok, one, in 50 years.
For those who say, just reload the 358 with pistol powder...Sure that will work, but that requires effort and time; sometimes guys just want to buy a box of pistol ammo and plink with their High Power rifle.
Different approach.
Last one I made was for a 450 Martini and the guy shoots 45 LC out of it. More like a little pop gun with that....it will hit a softball at 25 yards.
24 March 2025, 02:32
Rick RDPCD
Exactly! I’m in the market for one and only one, not a real reason to fire up a manufacturing plant. AND I fully realize that accuracy with .357 ammo could be anywhere from amazing to awful.
24 March 2025, 04:33
shootermetalThe guy in alaska makes them. I got a 9mm out of a 35 Whelen one for my rifle. dcpd is wrong. He also makes them pretty fast. The problem with the 357 on a 308 is going to be the rim on the 357 and the walls of the adapter are going to too thin. My 9mmer's shoot pretty good from the Whelen.
24 March 2025, 07:08
sambarman338An insert might make some sense for someone who does not reload, but would need to be taken out and returned between shots and would soon be lost.
26 March 2025, 05:48
Rick Rquote:
Originally posted by JFE:
This article will help you with ideas for a load for your 358.
https://leverguns.com/articles/paco/small_charges.htm
Thank you! That looks quite helpful!
quote:
Originally posted by shootermetal:
The guy in alaska makes them. I got a 9mm out of a 35 Whelen one for my rifle. dcpd is wrong. He also makes them pretty fast. The problem with the 357 on a 308 is going to be the rim on the 357 and the walls of the adapter are going to too thin. My 9mmer's shoot pretty good from the Whelen.
It took a couple days but MCA replied and you’re right, and I had never noticed how close in size the 308/358 rim is to .38/.357.
They can do 9mm. I have thousands of 9mm.
Sounds like it a match made in heaven, after you pay yer $40.
26 March 2025, 20:12
shootermetalquote:
Originally posted by Rick R:
quote:
Originally posted by JFE:
This article will help you with ideas for a load for your 358.
https://leverguns.com/articles/paco/small_charges.htm
Thank you! That looks quite helpful!
quote:
Originally posted by shootermetal:
The guy in alaska makes them. I got a 9mm out of a 35 Whelen one for my rifle. dcpd is wrong. He also makes them pretty fast. The problem with the 357 on a 308 is going to be the rim on the 357 and the walls of the adapter are going to too thin. My 9mmer's shoot pretty good from the Whelen.
Glad I could help and that it worked out for you.
It took a couple days but MCA replied and you’re right, and I had never noticed how close in size the 308/358 rim is to .38/.357.
They can do 9mm. I have thousands of 9mm.
Sounds like it a match made in heaven, after you pay yer $40.