.357 rossi bore measurement?

[mainiac]

havnt been here for a while asking questions..... I have a rossi .357 carbine that ive been shooting alot. It shoots so well that i havnt fooled with the load in hundreds of rounds. But, now im am wondering just how good this thing will shoot.Ive been shooting the rcbs 158 swc (with no check) and 7.6 grains of unique, and getting about 1 inch groups at 25 yards, and about 4-5 inches at a hundred (my eyes really cant handle this distants with the sights on the gun) Anyways,, will this gun shoot one hole groups at 25 yards? Am getting ready to start working on accuracy with this thing,and am wondering how well they really shoot??? My original question is this,,,,I slugged the bore and it has a tight .3555-.356 groove with a .348 land . Are all rossi,s choked this tight? Would you fellers size down to this diameter,or would you leave it .358? The barrell seems to be a good one as far as leading goes, with that 158 rcbs going at 1340 f.p.s. it doesnt leave any leading after hundreds of rounds,even though im not running a check on these(to cheap!) anyways, thanks,mark

[rmb721]

I have heard that you could use lead bullets that are .003 oversize. Sounds to me like yours isn't broke, so don't fix it.

[fecmech]

I have a Rossi singleshot .357 with a groove that is not quite .357. I run .358 bullets in it all the time with no leading. I have run 358429 plain base at a little over 1600 fps with decent accuracy. I mostly shoot my .38 rn's at about 1050 fps which are very accurate and pleasant to shoot. Good luck Nick

[Jon K]

maniac,

The Italian guns seem to use .3555-356 groove diameter. They shoot very well, although you need to watch brass for pressure stress. I had a Uberti 357 Lever, it was hard on brass. I used the RCBS and Saeco 180 grain bullet @1400 fps, for Silly Wet. I wish I would have kept the gun now.
The load you're using should be fine, 7 grains of Unique works good with the 160 grain also.

Have Fun Shooting,
Jon
:castmine:

[JRR]

Are you using a stepped gas check design without the check, or a flat based bullet? If you are using the stepped based bullet, then installing the check will probably halve your groups.
Jeff

[steveb]

I done a chamber cast on my Rossi 92 chambered in 357Mag and it was right at .356

[Bucks Owin]

I have heard that you could use lead bullets that are .003 oversize. Sounds to me like yours isn't broke, so don't fix it.

H. Guy Loverin recommended and used bullets of around .003" O/S....
I have used "as cast" boolits like that in my .357 and .44 with fine accuracy. (Albeit some leading occured but then I was using nothing but Lee Liquid Alox as lube too....)
FWIW,

Dennis

[S.R.Custom]

H. Guy Loverin recommended and used bullets of around .003" O/S....
I have used "as cast" boolits like that in my .357 and .44 with fine accuracy...

Accuracy, I've found, doesn't really care if you're .002", .003", or whatever, as long as you're at least .001" over. The most important factor in accuracy I've found, is to fill the throat as much as possible so as to avoid blow-by at ignition. If that means as much as +.004", so be it. Just watch for pressure.

[Bass Ackward]

Am getting ready to start working on accuracy with this thing,and am wondering how well they really shoot??? Would you fellers size down to this diameter,or would you leave it .358? The barrell seems to be a good one as far as leading goes, with that 158 rcbs going at 1340 f.p.s. it doesnt leave any leading after hundreds of rounds,even though im not running a check on these(to cheap!) anyways, thanks,mark


Mark,

If you are considering going after accuracy, then cheap is going to stand in your way. You see, different bullets may require different sizing. How do you know? testing. A simple .002 over bore can be a ball park. And if that is all the gun is capable of, or you are satisfied, then it will appear a saving grace. But if a gun is capable of much more, then you need to play with sizing and adjust load slightly up or down until maximum performance is reached.

Seating depth also plays a LARGE part here. The larger the bullet, often the smaller the bullet jump. So daimeter can fix other sins. Dad has a early 50s 30/30 that will shoot most cast into 1 1/2" sized .311 at 100 yards. At .311, a 311440 is a 2 to 2 1/2 inch performer which is good for game, but kinda discouraging. That is unless you size to .3095. Then it will go to 3/4".

If you simply accept one diameter, you may make incorrect judgements on certain bullet designs and accept standard bullet diameters. Remember, when you condem a design as "poor shooting" they are still sold because they are working for somebody. Why not you?