want to drive a 250 gr .357 to 1000 fps with H110, BD, or 4198; mag or max case?

[357Mag]

Whiterabbit -

Howdy !

I read a post @ one of the shooting websites, from a guy that did ballistics lab work. He talked about efforts he made determining what charge level for each of several powders would result in " ringing the chamber ".

H4198 was one that was tested. In the end, his recommendation was to not use less than 70 % of the charge it took to fill case to base of bullet.

He also mentioned that any charge wt of 2400 could be used, and yet the chamber was not damaged. As regards this latter info, we note that 2400 is close in burn rate to WW296/H110; and both are used in .357Mag reloads by many. This would seem to imply that any initial loads worked-up w/ a sensible charge wt of 2400, would give you a good & safe starting point

I'll point out that Hodgdon lists H4198 as an "extreme rifle propellant ".
H4227 is not described individually on their website, the way most of their other powders are.
Perhaps they were being selectively non-commital, with an eye that 4227 could see use in both rifles, carbines; and handguns ?

For a top-break " test mule ", might I suggest you take a look at an H & R SB2 ULtra rifle; in .357Max ?
I say this because I had one, and I could not get even minimally seated .358" cal 200gr bullets to touch the rifling. This would seem to imply that (perhaps ) your longer/heavier chosen bullet might be able to reach the rifling in one of these rifles; while the bullet not encroach the powder spaced too severely ? Hmm....

IMHO -
.357MAx, .357 B & D; and .357AutoMag all can run charges like 24gr WW296 under a .357" cal 158gr boolit.
Rather than start w/ a case capacity of the sizes just listed above and deeply seat a boolit into it, ideally.... you would start w/ a larger-capacity case; and let the deeply-seated bullet itself limit the available powder space.

I've been doing a lot of reduced load work w/ .35 Rem in my Marlin M-336 XLR; and bullet/boolit weights of 140 -180gr ( not the 350gr you mention, though ).
The rifle has a 24" 1-16 12-groove barrel. My charges of H4198 were so low that I could not reliably stabilize Hornady 180 SSPs.
I have been able to shoot w/ pretty good results both Rem .358" cal 150PSPs, and the turned brass .358" cal polymer-capped 150gr Extended Range " Raptor " bullets from Cutting Edge.

My point:
With the monster boolit wt you describe and the desired low vel, I'm wondering whether any of the common factory-made .35 calibre single shot rifles have the twist rate needed to stabilize your chosen boolit ?


With regards,
357Mag

[rundownbear]

Remember guys....he wants a RIMLESS case...

[paul h]

(sic)

He also mentioned that any charge wt of 2400 could be used, and yet the chamber was not damaged. As regards this latter info, we note that 2400 is close in burn rate to WW296/H110; and both are used in .357Mag reloads by many. This would seem to imply that any initial loads worked-up w/ a sensible charge wt of 2400, would give you a good & safe starting point

(sic)

ABSOLUTELY NOT!!! This could be extremely dangerous advice.

H-110/W-296 have a heavy deterrent coating and must be loaded to near max levels for their starting loads. Failing to do so can result in the primer moving the bullet into the lands, the powder not getting sufficiently ignited to continue the bullets travel down the barrel and then the powder starting to burn with an obstructed bore. Several fire arms have been destroyed and people injured by downloading H-110/W-296.

2400 is a faster powder than H-110/W-296 and can be safely downloaded. But using 2400 starting loads for H-110/W-296 starting loads is not recommended.

[DougGuy]

ABSOLUTELY NOT!!! This could be extremely dangerous advice.

H-110/W-296 have a heavy deterrent coating and must be loaded to near max levels for their starting loads. Failing to do so can result in the primer moving the bullet into the lands, the powder not getting sufficiently ignited to continue the bullets travel down the barrel and then the powder starting to burn with an obstructed bore. Several fire arms have been destroyed and people injured by downloading H-110/W-296.

2400 is a faster powder than H-110/W-296 and can be safely downloaded. But using 2400 starting loads for H-110/W-296 starting loads is not recommended.

He's not implying it is safe for using H110/296 for starting loads, the powder in discussion for starting loads is 2400.

[Whiterabbit]

I'm still reading through the replies, thanks for the insight guys

You mentioned rimmless. This makes me think you want to try using 5.56 / 233 brass. On a couple of similar threads, I have promoted a gun that will fire either a rimmed or rimless versions of the DW 360.

So, yes, originally. The thread was prompted by finding 9mm win mag cases on starline's website, available now, for cheap. But the case length is 1.15"-ish instead of a cut-down 223 case which would be 1.5" (and adjustable by me, depending on how much case capacity I really need). Bullets I'm looking at (including that Accurate below) puts about .45" of bullet into the case. So, the question in my head is, does (very roughly), .6-.75" of powder space inside a straightwall case give me enough space to use either Bluedot or 4198 (or H110) to drive that bullet to 1000 fps?

Because if so, I don't even need to wildcat or case convert, just use 9mm win mag from starline.

[paul h]

He's not implying it is safe for using H110/296 for starting loads, the powder in discussion for starting loads is 2400.

I read his suggestion as using 2400 starting loads for H-110 starting loads. As the OP mentioned H-110 and not 2400 it seems I misread the post.

Sorry 357mag

[357Mag]

Paul h -

Howdy !

No problems, Mate ! I should have been more clear.

I shoot WW296 exclusively, as my .357Mag propellant. I shoot a minimum charge of 14.5gr w/ SP Mag primers, under ( typically ) 158SWcs.
That was the minimum charge Winchester ( Olin ) used to list in their reloading pamphlet.

I certainly appreciate PaulH ' sentiments.
I have no intention of going any lower in charge, for my .357Mag loads w/ WW296, as that would be opposed to manufacturer's directions.


With regards,
357Mag

[357Mag]

Whiterabitt -

Howdy, again !


Have you considered a 7 X 33 Sako case ( 1.311" oal ) mildly blown-out to a straight sidewall case ?
Major case diameters and rim diam run about .020" larger than those for a .223.

Just a thought.


With regards,
357Mag

It has same bolt face a 9mm Parabellum.

[P Flados]

The 9 mm mag case is 1.16" where the 357 mag is 1.29" or 0.13" less. You concept leverages off the possibility of seating the bullet out farther than normal to get either the same or slightly more effective case capacity.

The next really big question is target max pressure. You have not really said what gun or even what class of gun. For this diameter case, you will destroy brass before you hurt a TC Encore. Some break open actions are much less forgiving. A stout action opens up possibilities. Look up the 353 and you will see that they drove a 200 grn bullet from 357 case with at an OAL of 1.776" to 1596 fps from a FA revolver.

Although it is pretty easy to dream up a gun that will push a mega boolit to 1000 fps out of the smallest possible case, is this what you really want. What single shot gun is good with 9 mm mag brass that will not be better with a more standard rimmed round. If the barrel is "pistol short" (say 8" - 12"), the 360 DW round would probably be better (and I say this as someone who loves all of his 357 maximums). If you are talking short rifle, I would lean toward the 357 maximum. All three cases are now available from Starline.

If you really need rimless (say a particular bolt action), starting out with the gun chambered for 9 mm mag could make sense. You may even want to test the gun with cut off 5.56 before you buy a lot of brass. If the testing does not work out like you want, make the chamber deeper and go with the custom length converted 5.56 brass.

[357Mag]

All -

Clarification on previous response.

7 X 33 w/ case mouth & shoulder expanded and/or mildly " blown out ", to make a case that has constant-taper from base to case' mouth ( a straight line ).

If the case' side walls were .013" thick @ the case mouth, the case would be .383" diam @ the mouth ( .357" + .026" ).
That theoretical example works out to a case taper of .008" from base to case mouth.
In comparison, a 9mm Parabellum has .009" of case taper, a 7.65 Parabellum .011" of taper, 9mm Win Mag .012" of taper; 7.62 Tokarev .015" of taper.
Of the 4, the two 9mm's headspace on their case mouth; as would the 7 X 33 case, wildcatted to expanded its case mouth diameter to .357" calibre.


With regards,
357Mag

[Whiterabbit]

If you really need rimless (say a particular bolt action), starting out with the gun chambered for 9 mm mag could make sense. You may even want to test the gun with cut off 5.56 before you buy a lot of brass. If the testing does not work out like you want, make the chamber deeper and go with the custom length converted 5.56 brass.

Now that makes one heck of alot of sense.

[JMax]

We used to load an H&G 230 gr WC in a 38 spl case in 357 mag revolvers for bowling pins at Second Chance. The load used was 7.5 gr of Blue Dot and I got consistent 1000 + ft/sec out of Smith 686. This was not a compressed load but very close to it. Bullets were loaded such that the bullet was just just below the chamber mouth. I used WW brass.

[Whiterabbit]

Thank you JMax!!

[runfiverun]

take a look at slightly up sizing the 351 WSL it is already throwing a 180gr bullet at a good velocity.
backing things down a titch and upping the weight shouldn't be too much of a problem.
and it's a rimless case already in existence.
and it's near the 360 DW case in capacity.

that might be a pretty easy solution.

[robg]

2400 would be my choice as its very flexible in amounts of powder.195 gr cg boolits with 11.5 gr of 2400 gives 1250 fps in my trapper hope this helps.I'd try loads from 7gr upwards