.38 primers and their velocities

[Cherryriver]

For .38 Special, I settled on a Berry's 158 plated round nose with 4.5gr VV320 to make about 825fps in my four-inch Colts. I'd always used Winchester small pistol standard primers, since those are easier to get around here and I don't shoot too much Smith & Wesson anymore.

So I went to the Wisconsin State IDPA match a few weeks ago and went with the .357 Model, making up a couple of fresh boxes of the above-mentioned load.

Most of the way through the match, Mike the Rangemaster called me over the chrono station. Not hard to figure that one out, so when I got there and saw they were using an old K-frame to test loads, I thought, fine, if they run the backup set of loads through the .357 I should be okay. (My clapped-out four-inch Official Police chronos a good 20+fps faster than my pristine six-inch Model 28-2.)

No such luck. Instead of 825fps, a nice cushion of 35fps, they averaged something like 775fps, about 15fps short.

Embarrassing, especially since I shoot at that club pretty often.

The only change I could think of was... Federal primers. I had run low on Winchesters and just used what was on the shelf.

Anyone else see this huge power loss in .38 Special just by changing to Federals?

Bill

Edited August 27, 2007 by Cherryriver

[Carlos]

For .38 Special, I settled on a Berry's 158 plated round nose with 4.5gr VV320 to make about 825fps in my four-inch Colts. I'd always used Winchester small pistol standard primers, since those are easier to get around here and I don't shoot too much Smith & Wesson anymore.

So I went to the Wisconsin State IDPA match a few weeks ago and went with the .357 Model, making up a couple of fresh boxes of the above-mentioned load.

Most of the way through the match, Mike the Rangemaster called me over the chrono station. Not hard to figure that one out, so when I got there and saw they were using an old K-frame to test loads, I thought, fine, if they run the backup set of loads through the .357 I should be okay. (My clapped-out four-inch Official Police chronos a good 20+fps faster than my pristine six-inch Model 28-2.)

No such luck. Instead of 825fps, a nice cushion of 35fps, they averaged something like 775fps, about 15fps short.

Embarrassing, especially since I shoot at that club pretty often.

The only change I could think of was... Federal primers. I had run low on Winchesters and just used what was on the shelf.

Anyone else see this huge power loss in .38 Special just by changing to Federals?

Bill

I think you got hosed by a worn out IDPA chrono gun. Federals are usually HOTTER and should result in a higher PF, not lower.

All primers use Lead Styphnate.

CCI, Win & Rem = "Normal" formula lead styphnate.

Federal = "Basic" lead styphnate.

[revchuck]

Bill - And I thought I was the only one here who would admit to owning a Colt revolver...

My 4" OP and 4" M10s run about the same velocities. Most of my .357 Mag S&Ws run slower than the .38s. I don't know about the primer differences - but I've got fresh supplies of Federal 100s and WSPs, so I'll check it out over the Labor Day weekend.

[Cherryriver]

Admit?

Here I thought I was bragging.

Any chrono results will be helpful. Not towards my getting the DNF, but making me feel less dumb.

Bill

[KirbyAU]

Bill,

my experince is that Colt revolvers have much tighter bores than S&W's.

This would explain the lower PF you were dealt by firing your loads through another handgun.

Kirby.

[Cherryriver]

Kirby-

I am familiar with Colts being tighter. That was why I thought I'd still make power factor once they fired the ammunition out of my .357 Model instead of the house Smith. But it was not to be; I just missed by less.

Here's a better one- my 5 1/2" New Service 1917 is not only the fastest .45ACP wheelgun I've ever had, it's faster than my late-model M1991, by about 30fps. Not too many roundguns do that kind of thing. And the 1917's bore is, shall we say, not as smooth as it once was.

Bill

[superdude]

did i understand this right? they tested your loads in their revolver for PF?

if that's right, that's the problem. Different guns produce different velocity with the same ammo. even if the guns are the same make, model, barrel length, even if they came off the production line one after the other.

if i did understand that right, you NEVER use a different gun to test velocity. NEVER! the range folks should know this. ALWAYS test velocity of a shooters loads in the shooter's gun. ALWAYS!

The Speer handloading manual #13 goes into some detail on this subjects and provides test results from a bunch of 357 revolvers just to make this point. Twin guns can produce dramatic differences in velocity. And i've clearly seen this in 1911 barrels. Each gun (read barrel) runs different.

there is a short discussion of this at: http://38super.net/Pages/Factory2.html at the Published vs. Real Velocity section.

if i misunderstood the description i'm sorry for ranting.

superdude

[gose]

Haven't tried in my revolvers, but did a test a couple of months ago with my G34, since I couldn't get hold of any more Fed 100s. Loaded up a bunch of each at the same time to make sure nothing changed on my 650 and headed out to the range with my chrono. Over 30 rounds of each, the average velocity was(to my surprise) 932.1 vs 932.2. Certainly just a coincidence that it got that close, but at least it was close enough to not worry about switching to WSP

Edited August 28, 2007 by gose

[revchuck]

if i did understand that right, you NEVER use a different gun to test velocity. NEVER! the range folks should know this. ALWAYS test velocity of a shooters loads in the shooter's gun. ALWAYS!

In IDPA, the PF is measured from the max barrel length allowed in the division, in order to not have people loading short-barrelled carry guns to over-maximum pressures. Major matches usually have guns in each caliber available for this. In Bill's case, it wasn't necessary, since he already had a gun with the maximum allowed barrel length (I think the Colt .357s only came with 4" and 6" barrels). It wasn't clear from his post which gun was used, but he had the option of using his gun instead of the "range" gun for the chrono.

[Cherryriver]

I apologize for letting the storytelling get ahead of clarity.

At this particular match, they had a house Smith K-frame with a four-inch barrel. They used three of the seven bagged sample rounds (with 158gr bullets) to get a velocity around 745fps. One, of course, was taken apart to weigh the bullet.

When the PF came out too low (a 158 needs 791fps), the rangemaster had me give the chrono operator my four-inch .357 Model (which, incidentally, also came in five-inch as well as six, and I want one!) with which he then fired the remaining three samples, getting about 775fps.

Yes, it was with this exact gun that I had previously chronoed (with my own inexpensive unit) this load and gotten 840fps. The only possible changes I can think of might have been the primers, and maybe the temperature. Problem is, I recall, with a none-too-positive memory, that weather conditions were quite similar. That's why I was looking into the primer thing.

Since then, I ran some very similiar loads and have noted a velocity loss on those using Federals over those with Winchesters, but not this large.

Incidentally, the four four-inch Colts I regularly take to the range, Official Police, Diamondback, .357 Model, and Python, chronoed the new, hotter, replacement load within 20fps of one another, with only the Python being noticeably faster by a small amount. I settled on 4.8gr of the VV 320 and got a solid 865fps average on a 75-degree afternoon.

The mention of shorter barrels is right on. To get my snubs to make it, I need to run things up a bit more. My Magnum Carry hit the power factor about right on the head that same recent day with the 4.8gr load, and I believe that it's usually a little slower than the older D-frames like the Detective Special.

Book max, by the way, for a Rainier (instead of Berry's) 158 plated is 4.8gr. I went up to 5.0 without any overpressure signs whatsover (the empties dropped out like rocks) and got into the 925fps range with the four-inchers.

I understand that at many IDPA matches, factory ammunition like WWB 130gr FMJs are accepted without regard to tested PF. The WWB is so soft it makes you want to look down the barrel to see if it's really going off. I ran some long ago can only remember that it was far from 125K PF. I suppose I could have dodged the whole embarrassment by just stopping at Wal-Mart on the way, but you know how reloaders are... factory ammo grosses them out.

Guess it's just one of those things that happens.

Bill

Edited August 29, 2007 by Cherryriver

[revchuck]

I understand that at many IDPA matches, factory ammunition like WWB 130gr FMJs are accepted without regard to tested PF.

I chronoed the Federal version of this stuff, and it pushed the 130 grain bullet to a screaming 745 fps from a 4" gun. I've heard the Remington and Winchester versions are about the same. Some local clubs might permit it, but no major matches.

Edited August 28, 2007 by revchuck

[Cherryriver]

Being a Colt wheelgun guy in this neck of the woods is always lonely, so I'll try to ease that by adding a picture of the .357 Model rig in question for revchuck, anyway.

There's some miles on the old warhorse, but looks don't matter when the hammer lets go.

I should mention that this 1960 example has the best DA stroke of any stock revolver I've ever had, including Pythons.

Bill

[revchuck]

Sweet - an oldie but a goodie!

We're getting off topic here, though.

[yoshidaex]

would you happen to know what brand of chrono they were using? I've seen instances of X brand chrono values versus Y brand chrono values were different (one bullet shot thru both units skyscreens). IIRC it was a 30-40 fps difference. I'm not sure it'll help in your case (almost 100 fps). Was the chrono set up in ambient light or in its own enclosure with a artifical light source. The time of day/angle the sun is at and if its overcast can make a difference in the fps you'll get. Thats why at major USPSA matches you'll have a chrono station inside a box with artifical lights to eliminate the differing light conditions. All these little things may push it to the extreme scenario but its trying to prevent you from a DQ.

[Cherryriver]

I'm afraid I didn't notice the type of chrono. It was outdoors but in a covered area.

Two small points- the disparity was 65fps, and in IDPA it's not a DQ, it's a DNF.

Bill

[Keninaz]

I'm afraid I didn't notice the type of chrono. It was outdoors but in a covered area.

Two small points- the disparity was 65fps, and in IDPA it's not a DQ, it's a DNF.

Bill

Cherryriver,

Try firing over a different chrono and see what kind of results you get. It may be a chronograph problem.

Ken