357sig vs 357mag

The legends of the 357sig difficulty in handloading are grossly exaggerated. The ONLY issue is the possibility of bullet setback, something that is also a problem with other semi-auto rounds and is very often the prime suspect in 40SW KaBooms. I've never heard of a 357sig kB. Probably has happened, but rarely. Setback can be eliminated a couple different ways, the easiest being the use of any one of several powders that are compressed loads.

Technically, the Sig is supposed to headspace on the mouth, although in reality it either headspaces on the shoulder or the extractor (like most autoloader cartridges actually do).

Case length is not critical. I've never found an over-long case, even long enough to headspace on the mouth and I've never trimmed a single one ever.

I've never even heard of any problems with bullet seating or uniformity or case uniformity at all. Ever.

I love the "one trick pony" argument. Yeah, it's "one trick" is to do everything the 9mm can do and more, without exceeding SAAMI pressure and without needing special "over pressure" designations to do it.
 
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Pawpaw,

I was a little confused by your long answer. But as for as the question if I shoot out to 100yds, the question is yes. I shoot out to 230yds on a 22" diameter gong with numerous different handguns. I'm pretty sure I could hit a 100yd with ease with the .357 sig round. This is where my question came from. I was shooting my ruger Blackhawk in .357 mag at the for gong with a handful of glocks that I have. I was interested in the 357 sig model that glock offeres, but wasnt to knowledgable on the round. There has been some useful info on here, but, like in a lot of other threads it turns into another my gun is better than your gun. :D
Oh well, guess that's the way it goes. Thanks for all the info guys
 
Compared to what? .357Mag, or other common automatic pistol cartridges?

Other common auto cartridges is what I meant. I was little off topic since this is a mag v sig thread. But, there is no way that would be irrelevant if it were true.
 
"IMHO, it is just another very expensive 9mm+p+."

I hear this all the time. The only problem is that not all guns chambered for 9mm can handle 9+p+. But all guns chambered for .357sig can handle .357sig. That's why I believe .357 sig is better.
 
DubC-Hicks said:
"IMHO, it is just another very expensive 9mm+p+."

I hear this all the time. The only problem is that not all guns chambered for 9mm can handle 9+p+. But all guns chambered for .357sig can handle .357sig. That's why I believe .357 sig is better.

Not only that, but "+p+" is not even a real designation. It has no defined parameters. It literally means "beyond SAAMI designation". It could LITERALLY be any load level above the SAAMI "+p" designation.

In other words, the only way 9mm can match 357sig is by exceeding all published data.

People should check the reloading forum and get an idea of the general feeling among handloaders about exceeding SAAMI designated pressure limits.

Yet, 357sig matches these undefinable 9mm loads, in guns designed for the task and without exceeding industry established pressure levels.
 
I love my Coonan Classic because it shoots 357 magnums. When I chronograph the bullets they are slightly faster than my fathers S&W 629 which has a 7 inch barrel.

I have never had a problem feeding my Coonan Classic with any 357 magnum.
In fact the only round it does not like is CCI shot rounds. It breaks the blue plastic case and the BBs escape from the end of the barrel.

357 Magnum vs 357 SIG?
What is the difference between the two other than 357 SIG being automatic. Is there a difference in velocity or stopping power? Looking for someone with personal experience.

logan and doc and the rest are right on mark

The 357 magnum is loaded a little bit soft on purpose by the major ammo companies simply to reduce recoil (and also because in the old days 357s were built on big N frame type revolvers) If you look at smaller ammo companies, you can get truely full powered 357 magnum loads taht will roll your socks up, or you can handload them.

357 sig set out to match ONE specific loading of 357 magnum in a relatively short barrel, and came close. However, you move beyond that one loading and the 357 sig cannot compete any more, especially with heavy bullets of 140 grains and beyond.

With the proper bullet (say a 158 grainer) the 357 can be a good hunting gun, that will never be true of the 357 sig.

Load a 357 magnum in a 6 inch barrel and get a good boost in performance, in a lever action carbine and you can drastically increase it's performance. The 357 sig has been designed around a short barrel, longer barrels will do little to help it.

The two things the 357 sig has going for it is 1)more shots before you run out, 2)faster reloads

http://answers.yahoo.com/question/index?qid=20080209233725AAMB0Eo

I think this guy pretty much sums it up. You can all so compair exotic ammo makes like buffalo bore to see what the real potential is.

both from 4 inch barrels and 125 grain bullets

(357 Magnum) = 1603 fps
(357 sig) =1,433 fps
 
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Yet another boooorrrrrring which is better .357 Sig or 9mm
thread. There are a lot of law enforcement agencies that have
adopted the .357 Sig and a lot use 9mm and still more use the
.40 S&W. They all have their advantages and disadvantages.
 
trex312 wrote

<<<Yet another boooorrrrrring which is better .357 Sig or 9mm
thread.>>>

Wrong. This is another which is better, 357 Sig or 357 Mag thread.

Mondays are when we discuss "Which is better, 357 Sig or 9mm?"
 
Wrong. This is another which is better, 357 Sig or 357 Mag thread.

Mondays are when we discuss "Which is better, 357 Sig or 9mm?"

very true.

Latter in the week we will have 357 magnum vs 10mm, 45 ACP vs 45 GAP, 38special vs 380acp and every body's Favorite Revolver Vs Automatic :rolleyes:
 
A couple of people already posted the correct reply, in 125 gr. loadings the 357 Sig does match the 357 Mag out of similar size CC guns.

I had a Ruger Speed Six 2 3/4'', it shot the Federal 125 JHP Mag @ average of 1,248 fps / 432# KE

My Glock 32 and 33 can easily do better than the "legendary" Mag load when fired from a short barrel.

Glock 33 (3.5'' barrel) Gold Dot 125 gr. @ 1,315 fps / 480# KE
Glock 33 (3.5'' barrel) Cor-Bon 125 gr. @ 1,324 fps / 486# KE
Glock 32 (4'' barrel) Gold Dot 125 gr. @ 1,334 fps / 494# KE

Before anyone points out how the Glocks had a longer barrel, remember that a semiauto includes the chamber when measuring the barrel, while a revolver does not. The Glock 33 (3.5'' barrel) is a very fair comparison to the Speed Six with 2 3/4'' barrel.

Sorry but the Speed Six pales in comparison to the Glock 33.
 
I like them both, but I have 43 .357mags, and only 2 .357sigs.The sig seems to me, has a sharper recoil, and a different crack to it.
 
The .357 Sig comes reasonably close to duplicating the ballistics of older 125gr .357 Magnum loadings, but that's about where the similarities end. To understand the similarities and differences, you really have to understand the history of the .357 Sig cartridge.

During the 1970's and 1980's, 125gr SJHP .357 Magnum loadings (particularly those from Remington and Federal) gained a fearsome reputation for effectiveness when used against erect bipeds. Nearly all the police departments that used these loadings were quite happy with them until semi-automatic came into vogue for police in the 80's. At that time, the two main cartridges used for police semi-autos were 9mm and .45 ACP as neither .40 S&W nor .357 Sig had been invented yet (10mm was around, but it never really gained a huge following). Between the two, 9mm was far and away the more popular because it gave the most significant capacity advantage and capacity was the primary reason for switching to semi-autos in the first place.

The problem was, and to some degree still is, that you simply cannot make a semi-jacketed bullet completely reliable in a semi-automatic handgun. JHP bullets of the 80's and early 90's were, by today's standards, fairly primitive and, with 9mm in particular, you either had to go lighter and faster at the expense of shallow penetration or heavier and slower at the expense of aggressive and reliable expansion. This had never been an issue with the .357 Magnum because SJHP bullets expanded much easier than JHP's of the time and because the .357 Magnum could drive a bullet of a given weight much faster than a 9mm could.

It was then decided that if the same weight bullet could be driven at the same velocity of the 125gr .357 Magnum loadings in a more semi-auto friendly package, that the effectiveness of the Magnum could be successfully transitioned to a semi-auto platform. Unfortunately, it was an idea that worked much better in theory than in practice.

Early .357 Sig loadings did indeed live up to the Magnum's ballistics (125gr bullet at 1450fps), but they did not use the same types of bullets. Early .357 Sig loadings used standard 9mm bullets which were designed to be driven at 1000-1200fps. When driven 200-250fps beyond their designed velocity window, these bullets would frequently overexpand and/or fragment resulting in relatively shallow penetration. The cure for this issue was two-fold: first, most manufacturers dropped their velocity by about 100fps to approximately 1350fps. While at the upper limit of velocity, many 9mm bullets could still hold together well enough to penetrate adequately at 1350fps. The other solution was the the bullet makers designed newer, tougher bullets better suited to higher velocity than the older 9mm bullets were.

That brings us to the .357 Sig loadings of today: most run a 125gr bullet at approximately 1350fps with expansion and penetration similar to that of the newer premium 9mm and .40 S&W loadings. While that is certainly good performance, it is not the same as what a .357 Magnum is capable of.

The most obvious difference is the range of bullet weights available. Very few .357 Sig loadings exist with bullets heavier than 125gr and the few that do cannot come close to matching the velocity attainable from 140gr+ .357 Magnum loadings. Also, while 1450fps was the approximate velocity of older 125gr .357 Magnum loads, it is nowhere near the top end of velocity for that bullet weight in that cartridge. Boutique ammunition makers like Buffalo Bore, Double Tap, and Grizzly have produced 125gr .357 Magnum loadings that can crack 1600fps from a 4" barrel and even more from a longer tube. I know of no maker with a .357 Sig loading faster than 1500fps from a common semi-auto.

Bullet construction makes a big difference too. When loaded with modern bullets like a Speer Gold Dot or Hornady XTP, a 125gr .357 Magnum is capable of much deeper penetration than a .357 Sig is. Brass Fetcher did a test of a .357 Magnum 125gr Speer Gold Dot which went through over 16" of ballistic gelatin, most .357 Sig loadings run in the 12-14" range. Finally, the old SJHP bullets do not perform like JHP semi-auto bullets do. While penetration was reasonably similar to modern JHP's (11-13"), the expansion characteristics are very different. The SJHP, when driven at high velocity, routinely shed their jackets in large shards at 6-10" with the lead core still penetrating 11-13" while most JHP's designed for semi-autos tend to either fragment very little to none or fragment very quickly with total penetration of less than 10" (6-8" is fairly common).

.357 Sig is certainly a more than capable self-defense cartridge, but it cannot duplicate the .357 Magnum beyond paper ballistics due to the constraints of its design and the platform for which it was designed.
 
with so many knowledgeable 357 folk following this thread, i feel inclined to ask. WHY BOTHER LAODING YOUR 357 MAG WITH 125GR?? anything below 140 seems a waste to me, i prefer 158, but am more then happy to use 160, 165, or even 180. i just dont understand carrying the lower weight rounds? thats like loading 80gr in your 9mm when you could have 115, or 127.why would you?:confused:

hopefully there is a reason forth coming.
 
I think it has to do with the energy and the history. Historically speaking the 357 magnum federal 125 grain load is the #1 man stopper (if you buy in to those numbers)

One of my favorite loads from my Coonan uses a 110 grain bullets and H110 powder, it makes impressive fire balls and shock waves.
 
The 357 mag revolver is more versatile in that it can shoot heavy bullets through longer barrels. This is an advantage when hunting or for long range target shooting, not for SD against humans. When using 125 gr bullets which are the best choice for SD, the 357 Sig equals the 357 mag revolver.

For that matter a 9mm+p is close enough to not matter. Forget published ballistics numbers. The numbers you see published are through 357 mag guns with 8" test barrels. When fired through actual 4" or shorter barrels with a cylinder gap to steal even more velocity the 357 mag does not look nearly as good as it does on paper.
 
Vincent,
That's a good question...
The 125 grain has an excellent reputation as a manstopper/fight stopper with Indianapolis Police Department and Kentucky State Troopers (when they used revolvers). The 125 grain from a 4" clocks around 1400 ft/sec. and from Buffalo Bore 1485 ft/sec. which equates to 544 ft/lbs to 700 ft/lbs of energy. Sectional density of the 125 grain bullet is typically .140 (honestly, not sure of all manufacturers) compared to .177 of a typical 158 bullet in .357. A hot loaded 158 grain 1400-1485 ft/sec. equates to a muzzle energy of between 688 ft/lbs and 774 ft/lbs. Given the increased weight and sectional density of the 158 grain .357. I believe over penetration and increased recoil were possible concerns with the aforementioned departments. Perhaps some gifted poster might be able to determine how much of the larger bullet's energy is expended in the target as it passes through (if it does). I have carried everything from 110 grain to 158 grain .357 in my revolvers. Currently I carry 145 Grain Silvertips in my snub. It's winter and I prefer a heavier weight with higher sectional density for what I perceive to be optimal penetration. I don't think you can hardly go wrong with any grain of 110-158. I like 180 grain for hunting deer and hogs in JHP or Hardcast.
 
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