Some reloading quesitions and confusion

[RHarris]

I haven't been reloading for very long, but have successfully fired a few hundred without any problems. However, there are a few things I haven't figured out.

I'm reloading .38special. I have cast lead 158gr semiwad cutters and 148gr double-ended wad cutters. I have a can of Bullseye and some Accurate No 5. Until recently, just about all of them were very light loads consisting of the 158grSWC's and Bullseye powder. These will be fired from a 4" GP100 .357.

My current goal is to achieve the best target accuracy and keeping things safe. Any suggestions would be very helpful and appreciated.

I have not trimmed any brass and just recently acquired calipers. All of my brass is longer than the case length of 1.115 indicated int loading manuals. While measurements are consisitant, the length of some of the cases is up to 1.150. These do fit in the chamber just fine, but it's a 357Mag chamber we're talking about. Is the 1.115 specification a "maximum" dimension? Since these fit in the chamber just fine, does this matter? How critical is a few thousanths of an inch in case length variation when trying to achieve the best accuracy?

I've also noticed some variations in overall length after seating. Measured overall lengths sometimes vary more than ten thousanths when seating with the same die setting? Is this normal? None exceed the maximum overall length listed. Is case trimming necessary for this application?

Is there a simple way to "correct" listed loading data for the revolver being used? Some manuals indicate testing with 8" barrels. I'll be using a 4" barrel. It seems like they should differ significantly. Do that many people use 8" .38specials?

I'm not interested in really hot loads, but I want to progressively try different loads to find which works best. Different manuals are listing different maximum charges and I find that a little confusing. I'm not starting at the maximum, but as I approach it, at what point do I stop (assuming I don't see any evidence of too much pressure)? Is there a way to calculate pressure for different loads? Again, I could really care less about try to create some really hot load, but considering the fact that I can fire .38+p and .357mag, can I safely go beyond the "never exceed" value listed? There is no "+p" listing for 148gr wadcutters I can find. I would simply like to try something like that to see the results, but won't if there a reasonalbe risk.

Starting loads are equally confusing. Manuals list "recommended" starting loads or suggest starting with 10% of never exceed loads. The Lee manual I have suggests starting with 2.5gr of Bullseye when using a 148 gr lead wadcutter. The never exceed load is 2.7. Using tenth grain increments, that's three different loads with those components. Even worse, the difference between the volumes of powder when changing just one tenth of a grain is very very small. I guess a very little can make a lot of difference. I'll try charges less than 2.5gr, but how far can I go that direction? Do I just keep reducing it and observe what happens? What is safe?

Am I likely to observe significant differenes between the Bullseye powder and AA5? The bullseye seems to be some dirty stuff and more leading seems to occur with it.

Should there be significant difference between the 148gr wadcutters and the 158gr semiwadcuters?

[labgrade]

Two manuals I just checked state the nominal .38 case is 1.155"

"Critical" for accuracy comes into play more with your crimp. Since this is a function of case length, longer cases will get crimped "harder" than shorter ones - all else being equal. I wouldn't worry about a couple thousands variance. Fact is, I can't remember the last time I checked case length for either .38 or .357 ...

Case length isn't going to affect your overall length (OAL). What's more critical in the measuring for this is a consistant application/use of the calipers. Sometimes too, minute "defects" (call 'em variances) in bullet tips, etc. will give different readings when everything is actually "the same." Again, I wouldn't get overly concerned.

No corrections that I'm aware of. Various companies use different types of test barrels for developing their loads & one reason why you'll see such velocity/starting/max loads is type of bullets used. Some have harder jacket material which causes a bit higher pressures. Brass too has an affect as it's all pretty much based on internal volume of the case (& seating depth of the bullet, etc.). Thicker brass = less internal volume. Lots of variables tend add up pretty quickly. Too, some companies may be just more conservative in their "findings."

Just because you have a .357 doesn't mean that you should ever try to exceed max loads in a .38 case. Due to that volume thing, you'll end up boosting pressures very rapidly & on into the "don't go there" land. If you want .357 stuff, load it in .357 brass. & no sense whatsoever to try to push wadcutters "up there." They'll do the trick very well, thank you, at their intended lower velocities. Wadcutters are swagged of pretty soft lead & if pushed beyond, oh, 1000fps or so, you'll likely end up with leading problems.

My standard Bullseye load for 148gr wadcutters (any mix/variation of 148gr WC bullets, primers, brass) is 2.7grains. Hornady's manual shows start at 2.5 & end up at 3.7grs
Since Bullseye is a fast burning powder, you don't need very much & it's one of the easy ones to double-charge = be careful.

Too, strange as it seems, reducing powder loads below that listed can get you into trouble as well. Especially with some of the slower burning rifle powders, detonation can occur with too littel powder. Stick with published data till you've had a few more under your belt & legitimately know when/what rules are OK to bend a bit.

[Dogjaw]

About the only thing that can be added to labgrade's answer is try loading the wadcutters in 357 brass. Don't forget to look up the load data for powder, it is not the same. Like the man says, keep the speed under 1,000 fps, or you'll lead up the barrel. I had more luck with accuracy using 357 instead of 38 in my S&W 586.

[WESHOOT2]

First, I own two 4" GP's, and have loaded 148- and 158g, and I have used Bullseye and AA5.

Next, YOU need to define (at least for yourself) "best accuracy". If you are TOTALLY committed to the very very best possible accuracy then EVERYTHING matters; if you wish for "very good accuracy" then less rigorous measures may be employed.

For BEST: new cases (recommend Starline) trimmed to uniform length (doesn't matter what length, just uniform). This can be accomplished inexpensively with the LEE trim tools.

Use Federal or CCI primers.

Suggest Bullseye for best accuracy; also try W231. Time-proven.

Seat bullets to uniform OAL using REDDING Competition Seating die.

Crimp.......crimp should be EXTREMELY UNIFORM. Highly recommend crimping with the REDDING Profile Crimp die. I use a fairly heavy crimp; suggest starting with an extremely LIGHT crimp and SLOWLY increasing crimp until best results are found.

Now for loads..........

You can perhaps exceed some manual's recommended MAX loads, but you MUST understand the risks. (ALWAYS ALWAYS ALWAYS wear safety glasses!)
GP's have a large safety margin, and are among the very strongest 357's available, so rest easier.
BUT.....
You can blow up any gun if things go badly LOL.

I have loaded as low as 148g/1.8g Bullseye and still had the bullet exit every time (biggest danger -- bullet lodged in bore!).
I have never felt the need to push this bullet, but have loaded the 158's to fairly high velocity, based on specific bullet. Not all bullets are equal, even when configured the same and of equal weight. The material is the difference, and sometimes the shape changes the friction surface (the portion that physically touches the barrel).

Do you have a chronograph? (Recommend PACT ONE.)

Can you list your specific components and loading tools?

What manuals do you have?

Isn't this fun?

[Freedom in theSkies]

Bravo!
You seem to be on the right track.
I have loaded 148gr. swc bullets fir a reasonably accurate round, with 3.6 gr. Bullseye, 4.0 of Unique and 3.7 of Green Dot.
I just picked up some 700X and will work up loads for that.
The cases should be the same length for a consistent crimp.
I have found that most pistol powders burn sooty in light loads, but tend to clean up with a bit more pressure. Whadya do?
I have also loaded these bullets in .357 cases and I increase the powder charge by .1 gr. for them.
Best o' luck!

[Bill Adair]

R,

Lots of good info already offered, so I can't add much.

I've heard that HBWC bullets can actually shed their skirts when loaded too hot, so I'm not pushing mine even to max loads. Double ended wad cutters should be no problem.

I never shoot .38 cases in my GP100 (also 4") for two reasons.

One is soot and carbon build up ahead of the case mouth, which is only a problem if you try to slip .357 rounds into those dirty chambers.

The second, is that your bullet is basically unsupported at the front end as it leaves the case, and until it reaches the throat of the chamber. Some claim it can tilt slightly and deform as it enters the throat, which may be compounded when it next hits the forcing cone less than square on. This may be pure bull, but it seems possible.

I second the recommendation for Starline brass, but starting with new brass of any kind, gives you a good start on consistant crimp grip and case tension. You will probably never see a difference, but at least it will eliminate one variable.

Use good bullets. I use nothing but Oregon Trail bullets. I've found them to be extremely consistant, very accurate, and they do not cause lead buildup in any of my guns! I've used many thousands of them over the past three years, and have yet to find a single badly cast bullet!

Bill

[Dogjaw]

Talking about brass. I once bought a bunch of new 357mag Midway brass. I said once, because it'll never happen again. I got 3 reloadings out of them and they started splitting.