Need someone to check a .38 load for me

[spacecoast]

Hello -

Can someone run this through their software and give me a predicted pressure and velocity? Is this considered a +P load?

.38 special cartridge
125 gr. Berry's plated FN bullet (bullet length of 1.35cm or 0.53")
4.7 gr. Titegroup
Small pistol primer (CCI)
OAL of 1.44" (3.65cm)
Mild crimp with Lee seating die (FCD doesn't touch the .38 or .357)

Much appreciated...

[Unclenick]

No velocity without barrel length and whether it is a revolver or rifle (or some other chamber). That is because revolver barrel lengths don't include the chamber but rifles and other barrel lengths do. QuickLOAD doesn't have that bullet in the database, so you'll have to provide bullet length, too.

[spacecoast]

Sorry, please use a 4" revolver barrel. The bullet length is 1.35cm or 0.53", diameter is .357" and it is copper plated.

[SwampYankee]

Unclenick,

How reliably can you use Quickload for a revolver? I've used it myself but always been concerned because it does not account for cylinder gap. I can change some of the parameters to calculate velocity but what difference will the gap make on peak pressure? Or have you already hit peak pressure by the time the bullet crosses the gap? And I guess the throat diameter is going to have an impact too (a big gap will let a good bit of gas past the bullet and into the gap)?

[l98ster]

Well, just to give you an idea:

I just chrono'ed a new load for my 4" GP100. Here are the stats:

.38 special case
Winchester small pistol primer
158gr LRN

4.1gr titegroup = 837fps
4.2gr titegroup = 856fps
4.3gr titegroup = 873fps

Same rounds out of a 6" blackhawk:

4.1gr titegroup = 880fps
4.2gr titegroup = 902fps
4.3gr titegroup = 916fps

Since you are using a lighter, plated bullet coupled with a heavier charge than I did, I would DEFINITLY expect something around 1100 fps.

Remeber, plated and jackets bullets are different. Berry does not recomend to use their bullets beyond 1200fps. With the loads that you described, I am betting that you are going to be really close to that.

BTW, I would not recomend you using those rounds in a .38 special. The loads that I listed above are beyond +p pressures, so I am using them stricktly in .357 mag revolvers!!

-Good Luck
-George

[Goldy]

www.hodgdon.com

For what it's worth Hodgdon lists 125grain Hornaday XTP at 1069 fps with 5.0 grains of Titegroup in their +P section. No barrel length listed.

[spacecoast]

Unclenick -

FWIW, I would think this bullet to be very similar to the Rainier plated 125 gr. bullet. Perhaps QuickLoad carries that one.

Thanks...

[spacecoast]

Does Unclenick or anyone have the QuickLoad projection for this load?

.38 special cartridge
4" revolver
125 gr. Berry's plated FN bullet (bullet length of 1.35cm or 0.53")
4.7 gr. Titegroup
Small pistol primer (CCI)
OAL of 1.44" (3.65cm)
Mild crimp with Lee seating die (FCD doesn't touch the .38 or .357)

Thanks

[Unclenick]

Yes.

I get 17,115 psi and 1024 fps from the default settings.

If I run I98sters 4.3 grain load at 1.55" COL, I get 18,622 psi and 904 fps. He actually measured 873 fps. That difference is due to the barrel/cylinder gap and the fact QuickLOAD is really meant for bottleneck cases, so it is not uncommon to have to increase its default case volume a little to compensate for real behavior in a straight wall load. Also, QuickLOAD's default case capacities are often on the small side, and I don't have his actual case water capacity. Plus there are all the gun tolerances having an affect. In the case of I98ster's load , increasing the case volume to get 873 fps gives a peak pressure of 15,681 psi, which is likely close to reality. It is also not actually a +P load in his gun if that is correct. In a tight test barrel it may be?

If I run that same increased case volume with your 4.7 grain load and bullet and COL, I get 14,607 psi and 990 fps.

There is nothing to say his gun and yours are identical enough for that to be true exactly, but I'll expect yours to be in that range. If you chronograph it, pressure can be figured more exactly, as pressure, barrel length and velocity from a fixed weight of powder charge correlate well. Note that your use of a lighter bullet greatly affects the pressure from the load despite the larger charge as compared to I98ster's 158 grain bullet load. This is both because the lighter bullet is easier to push down the bore and because you have a little more powder space under yours, despite the deeper seating.

[spacecoast]

Unclenick -

Thanks very, very much for the detailed info. This is pretty much what I was going for, a "warm" load at the top of the regular pressure range or in the low +P range. My understanding is that +P starts at 17,000 and tops out at 18,500 (not sure if this is CUP or PSI). Any CUP info for that load?

[Unclenick]

It's both. CUP and PSI agree pretty well at the lower pressures. The way +P is arrived at is by multiplying by 1.1, then rounding down to the nearest whole 500 psi/cup. So, in this case:

17,000 psi × 1.1 = 18,700 psi, rounded down to the nearest whole 500 psi is 18,500 psi.

Note that the CIP (European standard) for .38 Special, according to my old Vihtavuori manual is 1600 bar which converts to about 23,200 PSI. QuickLOAD's database says the CIP standard is 1500 bar or about 21,750 psi. Either way, I have no idea why the difference from SAAMI is so great? SAAMI may be sweating more lawyers, or maybe we just have more old guns here or S&W Airweights and the like, and didn't want to let it get past the black powder load pressure it was sold in originally?