Loading up some cast 357's.

[grubbylabs]

So I have been loading up some cast 140 grain and 158 grain bullets for my 357. This morning I ran them through the chrono and the spread is pretty significant.

On the 140's it was over 100fps. And as you will notice pretty fast.

I am loading with H110. And I am nearing max but not quit there yet. I am not getting any signs of pressure or leading and the accuracy is out standing.

Here is the readings from this morning.
140 grain. Gas check.
1525
1500
1561
1602
1525
1632

158 grain
1347
1359
1365
1291
1302
1306

A few years ago I was loading a 265 grain gas checked bullet over 296. At minimum charge I had over 20 fps spread. So I bumped my charge up a grain and the spread was cut by half.

So should I really worry about the spread given the accuracy is good?

 

[Walkalong]

No, unless you like to shoot pistol at long distance, when a tighter ES is good.

 

[stubbicatt]

With H110 a firm crimp is pretty important, IME.

 

[Arkansas Paul]

So should I really worry about the spread given the accuracy is good?

I wouldn't worry about it.
Accuracy is #1.

 

[bluetopper]

The hotter you load with H110 the less spread you'll have and the better accuracy you'll have........well, that's my experience anyway. Individual results may vary.

 

[walnut1704]

Did you check to see if the bullets were pulling forward from recoil? Load six, shoot three, measure OAL of #6, shoot 2 more, check #6 again to see if the bullet is pulling forward.

 

[grubbylabs]

I'll check, but with the crimp I am putting on them, I don't think recoil is causing a problem. I learned about that the hard way the first time I loaded 44 magnum.

 

[walnut1704]

I'll check, but with the crimp I am putting on them, I don't think recoil is causing a problem. I learned about that the hard way the first time I loaded 44 magnum.

But like others have said, if the accuracy is there for what you need it doesn't matter. The low SD is suppose to indicate an accurate load, in that the pressure is constant. But there's so many variables that affect accuracy and SD is just one of them. But in theory if you get the SD down it should be even more accurate. You can't have too accurate a load.

You hear the "taper crimps are for auto cartridges" quite a bit, but if that were true why does every die manufacturer make taper crimp dies for revolver cartridges? Somebody is using them. I use them for bullets without a crimp groove.

A few decades ago it was fairly popular to crimp heavy Magnum loads twice, first with a taper crimp, then with a roll crimp. These days there's also the Redding Profile Crimp die, which is more or less both types of crimps in one die. I've seen a lot of claims by users that the Profile Crimp will drop the SD in Magnum loads with heavy charges of slow powders. You might consider one of those.

 

[Missionary]

Good morning
A couple items I would check are...
Check the bullet diameters. Are they the same.
Check the bullets fit to the throats of the cylinders... you may have a couple Fat diameter throats.
Check your brass lengths.. are they all the same which affects crimp.
Is all the brass from the same company and hopefully lot.
Check bullet weight... are they within 1 grain. If there are voids within the bullets then there well could be 5 grains differences.

If you are looking for accuracy and good slow powder ignition all these factors are important.
Mike in Peru

 

[TimSr]

I wouldn't lose any sleep over it. As you still have some room to move up, you might find the spread tightens up a little bit. As Bluetopper stated, 110 seems to get better the more you stuff in the case.

Case tension holds the bullet in place much more than the crimp. As long as your crimps hold the bullet in place without creeping out you are fine. Consistant crimp has greater effect on uniformity. Overcrimping can cut into, or deform the bullet, and should be avoided. .357, especially with cast bullets, is meant to be roll crimped in the cannelure. your load is nothing new that requires reinventing the wheel.

 

[grubbylabs]

All the bullets went through the same sizing die, so I would assume they are all the same diameter.

All the throats slug out pretty close if I remember right they were all .3575- .3578.

 

[ku4hx]

If you ultimate goal is accuracy; you're done. If your goal is a more technical one involving internal ballistics, you have a little tweaking to do.

 

[Walkalong]

I recently chronoed some HiTek coated 158 Gr SWCs in .357 using 14.5 Grs of 2400 with a CCI 500 primer. I logged six shots each, Powder Back, Powder Forward, and Powder Level. None of the ES or SD numbers were particularly good, but they shot very well.

-----PB-----PF----PL
HI: 1278 - 1298 - 1289
LO: 1178 - 1234 - 1193
AVG: 1234 - 1257 - 1241
ES: 100 - 64 - 96
SD: 35 - 25 - 38

 

[grubbylabs]

I think I will stick with what I have.

 

[Crashbox]

I shot a bunch of 140's a couple of years ago over my chrono using my standard target load of 7.5 grains of Herco. The ES was over 100 FPS but accuracy-wise they shoot just fine at 25 yards; haven't tried them further out though...

 

[murf]

good call.

murf

 

[ljnowell]

I recently chronoed some HiTek coated 158 Gr SWCs in .357 using 14.5 Grs of 2400 with a CCI 500 primer. I logged six shots each, Powder Back, Powder Forward, and Powder Level. None of the ES or SD numbers were particularly good, but they shot very well.



-----PB-----PF----PL

HI: 1278 - 1298 - 1289

LO: 1178 - 1234 - 1193

AVG: 1234 - 1257 - 1241

ES: 100 - 64 - 96

SD: 35 - 25 - 38

I too am a faithful user of the 14.5 grain load of 2400 under a 158 grain lead bullet. It's about as stout as I see a need for in a 357 load.

That being said the only time I ever fired them across a chronograph my results were similar to yours. The inconsistency did not show on the target though. They were very accurate.