Range Report: .38 Special w/ Rainier 158gr FP

[TheTinMan]

Gun: Colt Officers Model 38 (so shoot me )
Bullet: Rainier plated 158 grain flat point
Cases: UMC factory ammo, third reload
Primer: Federal small pistol
COAL: 1.455"
Powder: Win 231

Rainier says to use lead bullet data but my velocities didn't come close to any lead bullet data I found. I built a ladder from 3.6 grains up to 4.4 grains based on available data. At 3.6 grains, they were barely dribbling out of the barrel and I feared the last one was a squib (chrono showed it at 130 fps). Extreme spread and standard deviation data were a mess, along with the "groups", until I got up to 4.4 grains:

avg 670 fps
hi/lo 62
std dev 25

So accuracy was terrible and my velocities were way below lead data from any source. My Hornady manual shows 4.4 grains as the MAX for a 158 grain lead bullet. It does show 158 grain hollow points over 4.3 grains at 700 fps. That looks a lot closer to my results. For the jacketed bullets, their MAX is 4.9 grains at 900 fps but that load is rated +P. Sierra shows 4.9 at 850 fps as max for jacketed 158 grain bullet.

I don't plan to go all the way up to 4.9 grains, but do you all think working up to 4.7 grains in 0.1 grain steps is responsible?

As a side note, this revolver loves 3.5 grains of W-231 under a swaged 158 grain Hornady HBWC. Avg 834 fps; ES 36; SD 9; and a 5-shot group under an inch at 15 yards off rest. There's nothing wrong with the gun.

 

[OKFC05]

I load Berry 158gr plated by the thousands with HP38/Win231.
You won't get lead velocities because the friction is higher with plated.
The data you are look at is for standard .38 Spl. You can go into +P with plated bullets without problem; I have to go 4.5gr to make reliable minor, which is right at the edge of +P. 4.3 is good enough for ICORE and IDPA (120PF and 115PF). Plated bullets are not suited for magnum loads (like .357 full power).

My experience is that I get all the accuracy I am going to get around 4.3 to 4.5gr. I would not go to the TOP load for jacketed bullets, because the plated seal a bit better. I can get better accuracy out of lead WC, but I don't like the lube smoke for IDPA and ICORE.

By the way, be sure to clean ALL the fouling out of the barrel when switching between lead and plated bullets if you want best accuracy and minimal added fouling.

 

[ArchAngelCD]

I got a box of Berry's 158gr bullets and I also had to use more powder than with lead bullets to achieve similar velocities but I expected that. I usually charge 4.0gr W231 under a 158gr LSWC and I'm using 4.4gr W231 under the Berry's 158gr bullets.

 

[TheTinMan]

Update: I found the COAL listed above of 1.455" by taking the COAL for this bullet in .357 Magnum from some archived MidwayUSA datat for Rainier and subtracting the difference in case length between a .357 Magnum and a .38 Special.

Then I came across THIS DATA which appears to be directly from Rainier and shows a COAL of 1.430" for this bullet in .38 Special. Tried that with the most accurate load from before of 4.4 grains of W-231. And yes, I know that shorter COAL may increase pressure. There were no pressure signs at all, and based on the velocities I got before I wasn't even close to the maximum.

I wouldn't call it a light target load, but it is nicely accurate out of three different revolvers. I'm going to try a bit more crimp next time. This batch was crimped barely beyond a taper crimp. Some guys report better results with the plated bullets and a bit of a roll crimp.

 

[ArchAngelCD]

Then I came across THIS DATA which appears to be directly from Rainier and shows a COAL of 1.430" for this bullet in .38 Special. Tried that with the most accurate load from before of 4.4 grains of W-231. And yes, I know that shorter COAL may increase pressure. There were no pressure signs at all, and based on the velocities I got before I wasn't even close to the maximum.

The problem with checking for "signs" of pressure in the .38 Special, you will be way over SAAMI limits for the .38 Special before you ever see pressure signs. You can load a .38 Special round to 3X the max .38 Special pressure which are .357 Magnum pressures and see no pressure signs. You would have to exceed .357 Magnum pressures by at least 50% before you would see any signs in a .38 Special.

Not a knock on what you said, just a heads-up...