I have a Uberti baby rolling block in .357 mag. I would like to have a competent smith rechamber this sturdy little rifle to .357 maximum.

The gun is in excellent condition.

The sammi pressure for .357 mag is 35000
The sammi pressure for .357 maximum is 40000

Will this rifle safely take the pressure? If not, why? What is the weak link?

It has a very substantial chamber and barrel for a .357 mag!

Thanks.

I am a real fan of the .357 Max in a rifle. We have a couple of NEF that have been rechambered to the Max with a rifle reamer.
The best all-around load has been 20 grs of 4227 and the Hornady 180 fr XTP (crimped at the back crimp grove.)
Be very sure that the reamer for the Max is designed for a rifle and not revolver!
Regards, James

__________________
Dixie Slugs of Old Town Hammock, Florida
"Home of the Dixie Terminator Slug"

Thanks James, I will log that into my memory of things to know.

I just want to hear some feedback on this conversion on the uberti if others have done it, or, if someone has knowledge on the strength of the rolling block design. As mentioned earlier, I`m into safety first.

What is the big advantage and attraction of the 357 MAXIMUM over the 357 MAGNUM?

I mean, i know it has more velocity but the down sides are---Harder to get ammo. And if you use it for hunting what will the MAX kill dead that the MAGNUM won't?

I do like my little rolling block in 357 Magnum. It has plenty of spit for anything I might hunt.

What can I say? If yoiu are satisfied with the .357 Mag, you might not be interested in the 357 Max.
Now....The Max can be loaded with 200 ge bullets that matches the .35 remington (2000'/") with slower powders in the rifles.
Brass is available and .357 Mag loading dies work. The Max may not be best for those that do not reload. Powders like IMR4227 and even Re7 are excellent in the Max.
The fine 180 gr Hornady XTP bullets can be pushed at least 300'/" faster that the .357 Mag in the 357 Max. The BC of the Hornady 180 XTP is .230...so you can compare velocity between the two.
Regards, James

__________________
Dixie Slugs of Old Town Hammock, Florida
"Home of the Dixie Terminator Slug"

yeah, i hear you about the 300 fps add and the 200 grain boolits... that is worthy of pondering.
thanks,

To me, the allure of a 357Max is you get just that little bit more "oomph" without getting into a whole lot of recoil. It is definitely more powerful than a 357Mag, which is on the low side as far as a deer cartridge, and the Max puts you up close to 35 Remington numbers, which has long been a great woods round, for deer. With that being said, I don't know if this particular action is strong enough, although I have seen them chambered in 30/30 Winchester, which has just a little higher pressure rating than the 357Max.

Here's one of the best sites you'll find on the 357 Maxi in a rifle, Steve has put a lot of work into his site, and has even had pressure testing done on his loads.

http://357maximum.com/

sounds like a neat project.
what other factory chamberings did this come in? knowing that could tell you if it is strong enough for the conversion. I'll bet it would be OK
..

i would have to check the pressure rating on that little Rolling Block? We put the Max on the NEF rifle actions.
Bottom line is....I hunt with a S&W 686 - 6" with my Extreme Meplat Cast - 175 gr bullet, but would not consider the Max on a handgun.
The Max makes a nice little light walking rifle indeed!.....James

__________________
Dixie Slugs of Old Town Hammock, Florida
"Home of the Dixie Terminator Slug"

I ordered one of these through Taylor months and months ago, possibly last March? Anyways, it is being shipping to my FFL as I write this. The thing is probably being catapulted across a UPS terminal floor somewhere since afterall, it is Christmas shipping season. I am also interested in the upgrade to 357 maximum. Looks like it would be easy for a gunsmith to do. I reload quite often. All I would need is brass.

That ultra light baby Rolling Block is going to kick like a mule on meth with heavy loaded Maximums I would think... hmmmmmm.

The Uberti is available in 5.6x50RMag which operates at 49kpsi CIP, the 357Maxi operates at 45kpsi CIP, they both have about the same size case head at .377" and .379", so it should be good to go.

http://www.ubertireplicas.com/lever-babyrollingcar.php

http://kwk.us/pressures.html

http://stevespages.com/page8d.htm

Awwww, just get ya a good, tight-fittin' hat and squeeze a few off...it's only a pistol case in a carbine! I was surprised how much the 44 kicks in a lightweight, short firearm, so I'm sure a ULBRB in 357MAX would be a hoot ta shoot!

Thanks for the links
Yup, I have the gun in .357 mag in your top link.
I see how the pressures in the 5.6 x 50R mag is higher than than the .357 mag, and it`s case is just .002 small in diameter. Very good observation, thnak, it helps and give me confidence to investigate this conversionm further.

The new uberti rolling blocks http://www.uberti.com/firearms/1871_...er_carbine.php

look very similar to mine. The weight of them is the same at 4.8 lbs, so I suspect that the action and barrel diameter are the same too.
The barrel on mine is 22 inches ,as is with the newer ones too.
They seemd to have dropped the old calibers and gone with 45 70, 38 55, and 30 30 for the new guns.

I contacted Uberti, whick seems to be Benelli, and asked them the same question as I have asked here..... and the reply was that they do not know anyone who has done this conversion with the baby RB, and so they could not reccomend it. Pretty much what I expected from them, but worth a try anyway. Prolly lawsuit-shy or something similar....

I shoot 180 gr hard cast with mine, and WANT the extra power of the maximum. I could care less about recoil......it`s a hunting gun.
Ever try 550gr bullets with a full power load in a marlin GG? Certainly, it can`t be as bad as that thumper, lol.

Hello all---I hate to rain on anyones parade but I do not think any gunsmith wotrh his salt would take on this conversion of this type! The original rifles of this type were made in rimfire blackpwder loadings. I understand that these new rfles are made of modern steel, but they are still a weak design. I have had three of these rifles pass through my hands over the years 2 .357s ad a hornet. One of the .357s and the hornet had oval chambers making the brass unsafe to reload. I believe these guns are only usefull for people who only shoot a box of ammo a year and do not handload. Zane

The Uberti baby rolling block also came in 5.6 x 50R mag., which has a higher pressure rating than the .357 Rem Max.

http://www.ubertireplicas.com/lever-babyrollingcar.php

Interesting.....
The rifles that you are talking about, what make and model were they?
When you say weak design, exactly what part of the rifle are are you meaning.
Always looking for others input and opinions on the subject.