Home Forums Reloading Big Game Rifles .357 Maximum

Call JES. If he hasn't cut the chamber then ask him to cut it to 357 Magnum. Some rifle chamber reamers (I prefer Clymer's 357 Max reamer) are available with cylindrical throats. All mine have been 357 Mag chambers that were either rechambered with a Clymer 357 Max rifle reamer or were properly throated with a cylindrical throating reamer.

Bellm has experience with monoblocs.

Am I mis-reading or are you confusing "forcing cone" with "throat"?

My understanding is that revolver barrels have a forcing cone that receives the bullet as it exits the cylinder. The portion of a rifle chamber between the mouth of the case and the rifling is the throat. The leade is the portion from the end of the throat where rifling tapers from throat or groove diameter to bore diameter.

Bellm's SAAMI chamber drawings in the post Dinny referred to show a tapered throat with a breech end ID the same as the case neck OD and tapering to ?groove diameter at the front end of the throat. I assumed this was the "long throat" you referred to above. If I understood his description correctly Bellm asserts that the rear of the throat with an ID greater than bullet OD allows the bullet to tilt before encountering the lands.

So in effect the SAAMI .357 max chamber has a throat with a forcing cone profile which does not fully support the bullet between exiting the case mouth and entering the rifled portion of the barrel. A long throat is not necessarily a tapered throat.

So, I was wondering why the SAAMI chamber throat was tapered. And ,if Bellm is correct about other SAAMI straight wall revolver cartridge chambers, why Thompson Center would use a tapered throat in their rifle barrels.

This has been an interesting and educational exercise....and just the sort of thing I appreciate participating in 'fire discussions.

I called JES and left a message asking him to cut the chamber to .357 Magnum if his .357 Maximun chamber reamer did not have a cylindrical throat.

Well, the rebored barrel arrived today so my call to JES is moot.

I'll chamber some spent .357 cases to check out the ejector. It might need kissing with some fine grit wet dry sandpaper but I 'll wait to pass judgement after checking with fired and unfired cases. IIRC my Springfield, MA factory TC .460 S&W barrel ejector needed the sharp edges taken off.


I have 158 gr and 180 gr bullets, primers and H110, IMR4227, and CFE BLK powder. When I scare up some .357 max cases I'll report how it shoots. The LGS had a bag of .357 Max Starline brass a year ago very reasonable and I'm kicking myself for not grabbing it.

I have enough Maxi brass to share.

Dinny, PM sent

Hello everyone, I've been flollowing here and just signed up to join in.

So, I live in southern Illinois and Chikagostan has graciously allowed us to join the straightwall club. I'm a fan of the .357 Magnum and looking to improve on accuracy and range during deer season this year. I have two long rifles I can hunt with now in .357 mag, a Marlin 1894 levergun though I'll have to plug the tube due so single shot rules. I still dont get that one (3 shots allowed for a shotgun or whatever a revolver will hold, I have a .357 (7) rounder), but I digress.

I also have a nice Savage 24V series D in .357 Mag over 20 guage with a 24 inch barrel I pulled out of the safe that I shot for the first time last weekend. This would allow for a 20 gauge slug loaded as well, for up close or just in case. I'm always looking for that loophole. Its a bit long for a .357 magnum (not sure if a maximum round can take advantage of the extra length) but its a nice line for open sights. I had been thinking of having it reamed out for some extra thump and range, as these were also chambered in .357 maximum. However, I am concerned with some signs of blowby.

I ran about a dozen rounds of Federal 158gr. and some buffalo bore 125gr. down the barrel just to get a feel for the rifle and I noticed some powder residue around the rim and ejector, and the brass showed some signs as well. I am planning to slug the chamber to see if there is an excessive throat, discussed here, that may be the cause. I also noticed that the rifle barrel is not contained inside the monoblock that supports the 20 gauge barrel, it is somehow pinned or brazed on top of it. It's straight from camber to muzzle with no additional "meat" around the chamber area, as designed. If anyone has experience with these rifles or other recomendations please weigh in, I'm open to ideas.

Questions:

1. How much barrel length will a ".357 maximum" continue to develop usable velocity
2. What is the highest MV that could be expected at that length with 180gr. bullet (where is ballistic's by the inch when you need it)
3. Does anyone have any experience with Cutting Edge 160gr. Raptor (.335 BC) ER copper bullets (not looking at these for deer but they advertise 1500 fps for expansion) Dubious ?

It's a bit off topic here maybe, but I've been also looking at the .360 Buckhammer which I may say is probably the "perfect design for hunting in the mid-west straightwall states", with a bit of an edge over the .357 max. It's efficient, 35 cal has the best weight to velocity ratio for point of aim out to about 250+ yards with the right bullet (Fury !) I saw a beautiful Lipsey's Ruger No. 1 in .30-30 that would be a perfect platform for the .360. Only problem is, will it take off ? I think if the 350 Legend hadn't got a jump on it and it wasn't being pushed so hard by the AR fan boys it could. I'm not a fan of 350 and I think its a Kludge of a round. JMO Also, do I really need anouther caliber to reload !? Back to that in the future ....

FYI - I just spoke with Savage and as this is a Circa 1980 rifle they don't any support or knowledge of this rifle. They referred me to a gunsmith out of Michigan that responded:

1. We dont rechamber this rifle, and
2. Its probably nothing to worry about, its probably just not building enough pressure to expand the case.


Seems I need to slug this thing first.

Jozzle,
I would do a chamber cast and take measurments from the cast a few hours later to ensure the cast is settled.

I know of two guys who reamed their 24Vs to 357 Maximum. I'll direct one of them here to share his experience.

I have a Savage 24v 357/20 that I rechambered to Maxi.

Its a very good shooter. I do not remember velocity numbers but my 21" Handi was nearly 2100 and I pruned that to 17.5" and now its just over 2000 with same loading.

Generally speaking modern hi pressure cartritages net 40 fps ish per inch of barrel. So that close to what I see with my own H&R. So 3" more.. should aughta see 100-150 fps increase. Yes, there is a point of diminished returns. Where that happens is likely sooner as this Cartritage runs about 40k.

Blow back is generally, assuming its cut properly, only found on too low a pressure loading. On such a load pressure isnt enough to allow the brass to seal the chamber.

CW

Thanks Dinny. I'm working on getting a cast now.

And, that was quick. Welcome CW.

If I recall .357 Mag at max load runs out of steam at about 20". I'm looking for maximum velocity, I dont supose you remember your bullet recipe. Just trying to estimate where I might land with handloaded ammo.

Thats why I'm wondering about it being properly cut as I ran bufallo bore which is a pretty hot load. I was pretty surprised to see it blow back. I got interupted today but I'll try to get a casting in the next day or two.

Thanks for the input.

I have been popup and virus free for years running Linux. I just started an account here a couple days ago. Is anyone else getting on this site (only) geting Norton Antivirus popups ?

I am running Linux also and was getting the pop ups for a while but it seems to have stopped now.