New Rossi 92 357 magnum bullet stabilization

[massmanute]

My new (as yet unfired) Rossi 92 in 357 magnum carbine has a 1 in 30" rifling twist. How big of a bullet will it stabilize? I have been doing some calculations with several equations that that predict stabilization (versions of Miller and Greenhill equations) and they predict that you need about a 1 in 24" to stabilize even a 158 grain bullet, let alone something bigger, so I am concerned about the range of bullets that this rifle can stabilize.

Has anyone here done any testing, e.g. looking for keyhole prints in targets tests for various loads and distances?

Thanks.

P.S. I wonder why Rossi chose a relatively slow 1 in 30" twist.

[Lonegun1894]

With my 20" Rossi .357, I keep 158gr Lee RFN and 158gr Lee SWCGC stable out to at least 200yds. I cant say how much further because that is as far as I have shot them. At 100, I get 1.5-3" groups normally, but have not been able to do better than 5" at 200yds--yet. It is 2-3yrs old now so has the same 1:30" twist as yours has. I have not tried anything heavier as those are the moulds I have for this rifle for now. They do cast at 164grs for the PB and 168 for the GC versions after sizing and lubing if that helps you in any way.

My usual playing load is 7.0 grs Unique, but I have also used various doses of 2400 with the same accuracy, just higher MV.

[Baron von Trollwhack]

When I got one with that twist about ten years ago, I purchased jacketed bullet ammo in 125, 140, and 158 grain weights. Testing at 100 showed the 125s to be the very best. Unfortunately I couldn't drive 125 cast bullest as fast as jacketed and heavier alloy bullets gave larger groups. Deer yes, not foxes at 100.

BvT

[missionary5155]

Good morning
Well I would get ahold of about 100 180 grain GC types and have at it. I would first firelap the barrel with a good tight 158 grainer then start them 180´s with 10 grains of 2400. Load 3 at 10 grains and mark right up the scale at .3 grain increments. Probably will not be pretty till around the high end of the loads.
If 2400 does not get fast enough try 296 (H110). Start at 14 grains and again move on at .3 increments.
But I would not be looking to win any 200 meter matches if you have to shoot at clay pigeons. But for sure you will not have to worry about stripping a WW cast boolit.
Mike in Peru

[fecmech]

At lower velocities(1100-1300) the lee 125 rnfp is very accurate over 231 or Unique (I have not tried it faster). The Lee 9MM 120 TC is very close to the RNFP. I tried the NOE 185 rnfp over max doses of 296 and 2400 with no luck. The Lyman 358429 "Keith" at 173 grs over 15/296 or 13.5/2400 does 1600 fps+ and will average in the 3" range at 100 yds. The Lee 158 TL SWC is very accurate in the 1100-1200 fps range with Unique or 231. Everything I've mentioned here is good to 200 yds, that's the longest I've shot them. To date the 125 rnfp is the most accurate.

[Junior1942]

Mine stabilizes the 190 gr group buy @ 25 to 50 yards just fine; however, the 180 gr truncated cone LaserCast hits the target sideways. Every bullet below 180 gr shoots fine. As posted by someone else, mine likes 125 gr jacketed. The Lee 140 gr is its favorite cast bullet.

[massmanute]

Thanks for all The informative replies so far.

Junior, I'm new at the site. What is the 190 gr group buy?

[northmn]

Mine shot the Lee 158 tumble lubed bullet pretty fair. Biggest problem was that the sights would not adjust properly untill I modified the rear sight with a needle file to get it low enough to use a variety of bullets. I shot a lot of 38 specials out of it and a few moderate 357 loads. I also had to do a little work relieving the forestock wood fit as it wanted to vertically string.

DP

[Junior1942]

Thanks for all The informative replies so far.

Junior, I'm new at the site. What is the 190 gr group buy?It was a 6-hole 190 gr GC FP from a couple of years ago. There's lots of info including design print here somewhere.

[robertbank]

Out to 100 yards mine seems to handle the 158gr the best. No problem hitting a 6" plate at that distance. My eyes don't allow for much of a test at 100 yards shooting at paper anymore.

Take Care

Bob

[Junior1942]

Out to 100 yards mine seems to handle the 158gr the best. No problem hitting a 6" plate at that distance. My eyes don't allow for much of a test at 100 yards shooting at paper anymore.

Take Care

BobMine likes the Lee C358-158-SWC. RTL, mine weigh 165 grs in my ACWW alloy. With 15.2 grs/1.2cc of LilGun it runs 1775 fps from my Rossi 20" barrel. That's my favorite Rossi load for beer cans, bad guys and big bucks.

[robertbank]

Mine likes the Lee C358-158-SWC. RTL, mine weigh 165 grs in my ACWW alloy. With 15.2 grs/1.2cc of LilGun it runs 1775 fps from my Rossi 20" barrel. That's my favorite Rossi load for beer cans, bad guys and big bucks.

Do you use a gas check on those boolits and do you run them in .357 cases. I have decided to shoot mainly .357 cases in my Rossi to avoid the .38spl rings of the chamber. Thoughts?

Take Care

Bob

[Junior1942]

Do you use a gas check on those boolits and do you run them in .357 cases. I have decided to shoot mainly .357 cases in my Rossi to avoid the .38spl rings of the chamber. Thoughts?

Take Care

BobYep, gas checks and LLA lube. I shoot only 357 mag cases for the same reason as you.

[massmanute]

Has anyone tried the very hot Buffalo Bore factory loads in these rifles with the 1 in 30 inch twist? I'm wondering if the 158 grain and/or 180 grain loads will stabilize. If I ever take up hunting again it would be nice to know that the Buffalo Bore loads would work OK.

Of course, I could buy a box or two and try them out, but they are quite expensive and if someone else has done the work then I would rather learn from them than spend the extra money.