Ballistics by the inch .357

While looking up ballistic performance of the .357 Magnum I noticed a quirk in Ballistics By The Inch's data.

http://www.ballisticsbytheinch.com/357mag.html

It appears that Cor Bon 110 gr is significantly slower than the Cor Bon 125 gr. One would expect the lighter bullet, especially from the same manufacturer, would be faster.

Am I missing something?

 

No, but I've seen it before in other brands.

I don't know the answer, but I suspect they use a faster burning powder with the light bullet to cut down on muzzle flash, blast, and flame cutting damage to the gun.

So, it doesn't go as fast as you might expect.

rc

 

The 4" S&W 686 is considerably faster than the 6" Python and the 5" 627 with almost every load tested too. While not unheard of it isn't often that you see it so dramatically. The Python was especially slow.

 

Could it be that it's a lighter weight bullet, at lower velocity to cater to more recoil sensitive shooters?

 

No matter what, when it's a .357 MAGNUM it really doesn't matter. The tango is going down. In the end, it's all "much to do about nothing" and "angels dancing on the heads of pins" and "apples and oranges", it's all effective.

 

Maybe it's lighter and slower on Purpose? It could be a reduced recoil load like the 90gr .38 special that turns your revolver into a .380.

 

If one was to assume all loads are maximum loads, then it would be reasonable to expect the lighter bullet to have higher muzzle velocity. However, companies tailor different loads for different purposes. In the past, .357 loads in lighter bullets have earned the reputation as top strap and forcing cone burners. While there have been historically some hot 110g loads, they have now typically taken on the role of "light" loads.

 

I believe the 110 grain .357 loads have always been downloaded compared to the 125 grain loads. Meant to be easier on the gun and the shooter.

 

Corbin rates the 110/125/140 jhp at 1500/1400/1300fps respectively from a 4" test barrel, in case you want to compare that to the BBI chart. Carbon rates the 125 DPX at 1300 fps. BBI has that one at 1471 on the 4" test barrel in the top grid and 1438 from the Smith 4". Click on cylinder gap test link and look at the same 357 DPX. It's now 1246 from presumably the same 4" test barrel (no cylinder gap) and 1184 fps from a 4" barrel with a .006 gap, EDIT [154 fps less ] than the 4" Smith. I thing you have to take BBI with a grain of salt when things don't add up.


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I would want it to be slower. Imagine it being faster than the 125......if it could the h.p would open up further and not have the mass to push it through, therefore penetration would suffer badly. But if it's gobs of hamburger you desire in the first 5", well....

 

Could the questionable velocities be explained by different copper alloys in the jackets?

 

From a 3" revolver:
110 gr Winchester white box chrono'd 1200 fps
Speer 125 gr jhp 1375 fps
Federal 158 Hydrashock 1200 fps.
Reloading manuals show that the 110's can be loaded faster than 125's. The factories load them lighter.

 

I have the OP's site in my 'favorites', and while it's been useful, I've since found this site to be a much more detailed and useful site than "ballistics by the inch".

http://www.ballistics101.com/38_special.php

 

Then why not use .38 Special instead of a watered down .357?

 

The 100 gr and 125 gr bullets are identical designs by Cor Bon. From what I can tell, it appears that the 110 gr is just loaded with less powder.

 

It's my understanding that hot rodding a 110 grain bullet can cause forcing cone erosion as well as top strap flame cutting. They may be downloading them to avoid that.

Personally, I have no use for a 110 gr bullet anyway.

 

The issue with the lighter bullets is not that they're loaded more hotly, but that they're shorter, allowing the ultra-hot gases to escape earlier than they do with the heavier (i.e. longer) bullets.

 

I'd be willing to bet that the Python is the slowest because of the additional rifling land, and the 1/1000 inch taper in the bore diameter. Slightly more surface area in contact with the bullet when you have more lands and grooves, and the slight taper in the bore has to impact velocity a bit as well.

 

I believe the historical "big 3" ammo makers have always loaded the 110 grain load as a reduced power/recoil load. Factory specs are 110 grains @ 1295 fps from a 4" vented test barrel. Their full power 125 grain load was spec'd @ 1450 fps from the same test barrel. I believe full power would be somewhere around 1550 fps or closer to Corbon's specs. Not sure why but I think it was to have a more manageable load fired from snubby revolvers.

 

I would guess if you push the 110gr bullet too fast you won't get satisfactory penetration. Fast expansion added to a light bullet will not penetrate well at all.

 

110 is pretty good as is

When I started work with the INS back in the 1990's, they had changed over from .38 Special +P+ to the 110 grain .357 magnum load, although some officers still carried the +P+ on their belts.

The shift to the 110 grain .357 was caused by failures of the .38 Special load. We were issued S&W model 13's with 3 inch barrels because apparently, the DOJ had a big load of them that the FBI now refused to issue.

It was a nice enough carry gun in uniform or plain clothes at exactly 2 pounds loaded.
The 110 grain load worked well for us in the field, but you could carry the 125 grain load if you qualified with it. I did use it in my S&W 681.
We had problems with the 125 grain load splitting the forcing cone and could only use the 110 grain load in the model 13. It worked exactly as planned the several times my unit used it.

Back in the 1970's and 1980's, the 110 grain load was much hotter. I used some SPEER ammo and the muzzle blast knocked insulation off the range booth.

I am not bothered by the "watered down" 110 grain load. My agency had very good results with it. When I pull out my old .357 at night (rarely), this is the load I use.
It is much less noisy, with reduced flash and blast than the 125 grain loads, with the admission that the 125 grain loads were probably the most effective handgun ammo ever developed.

Jim

 

Remington pushes their 110 gr .357 mag round out the muzzle at 1,295 fps according to their ballistic data. The reason probably has more to do with accuracy and the bullet performance at the selected velocity than the potential to push the lighter bullet to a higher level. As short as the 110gr is a high velocity will likely cause fragmentation and insufficient penetration and may not remain as stable as the longer heavier 125gr. With 110gr JHP's experimented with I've never been able to get much better than passable good for accuracy while 125's and heavier have produced much better results.