Different powders for same results.

[Wheelgunner840]

Howdy all.

I have been reloading a lot lately. This year I started using Accurate Arms powders for a variety of calibers. Until now, I had pretty much stuck with W-231, 2400 and International Clays.

I am currently loading .357 mags. I have pretty much decided what velocity I want with each type and weight bullet. There are many varieties, but to make my point, I will only mention two here.

The first is a Hornady 158gr. HP/XTP traveling at 1250 fps.

The second is a 158gr. super hard cast LSWC, which I will most likely only push to 1000-1100 fps. This will be a target/practice loading.

I have AA#5 and AA#7. Both have loads listed in the velocity range that I am seeking to achieve. I realize that with AA powders, the lower the number on the bottle, the faster the powder is. For example, AA#9 has a more comparable burn rate to 2400, whereas AA#2 is closer to W-231.

Here is the question (finally!). Since both #5 and #7 will deliver the velocities that I am trying to achieve, is there any advantage to using the slower burning powder with the 158 grn. bullet? If I was loading a 180 gr. bullet, I would opt for the slower burning powder, and if I was loading a 125gr. bullet, I would use the faster burning powder. What, if any factor, should I be concerned with when loading the two above mentioned bullets?

Before you ask, the pressures are about the same with both #5 and #7, and there is no discernable difference in accuracy. I am thinking of using the #5 for the lower velocity LSWCs and the #7 for the higher speed jacketed bullets.

Just to confuse matters more, I have a lb of #9 on hand, and it is also listed for use with this bullet weight at the desired velocities mentioned above. I do think that #9 is a bit too slow burning for a 158 gr. bullet though.

What do you think? Any experience with loading the .357 with these powders?


WG840

 

[Wheelgunner840]

Howdy all.

I have been reloading a lot lately. This year I started using Accurate Arms powders for a variety of calibers. Until now, I had pretty much stuck with W-231, 2400 and International Clays.

I am currently loading .357 mags. I have pretty much decided what velocity I want with each type and weight bullet. There are many varieties, but to make my point, I will only mention two here.

The first is a Hornady 158gr. HP/XTP traveling at 1250 fps.

The second is a 158gr. super hard cast LSWC, which I will most likely only push to 1000-1100 fps. This will be a target/practice loading.

I have AA#5 and AA#7. Both have loads listed in the velocity range that I am seeking to achieve. I realize that with AA powders, the lower the number on the bottle, the faster the powder is. For example, AA#9 has a more comparable burn rate to 2400, whereas AA#2 is closer to W-231.

Here is the question (finally!). Since both #5 and #7 will deliver the velocities that I am trying to achieve, is there any advantage to using the slower burning powder with the 158 grn. bullet? If I was loading a 180 gr. bullet, I would opt for the slower burning powder, and if I was loading a 125gr. bullet, I would use the faster burning powder. What, if any factor, should I be concerned with when loading the two above mentioned bullets?

Before you ask, the pressures are about the same with both #5 and #7, and there is no discernable difference in accuracy. I am thinking of using the #5 for the lower velocity LSWCs and the #7 for the higher speed jacketed bullets.

Just to confuse matters more, I have a lb of #9 on hand, and it is also listed for use with this bullet weight at the desired velocities mentioned above. I do think that #9 is a bit too slow burning for a 158 gr. bullet though.

What do you think? Any experience with loading the .357 with these powders?


WG840

 

[Skip Sackett]

WG,
Just one thing to say. "Super hard cast" at the velocities you are mentioning has the potential to cause leading. There is a hardness/pressure relationship that should be maintained. Too hard with too little pressure is usually a bad thing. The bullet doesn't obturate and the gases escape between bore and bullet leaving one big mess. If it were me, I wouldn't use a "Super hard cast" bullet unless I was going to drive that baby into the stratosphere! over 1800fps or so. My homecast 158gr H&G #290BB is cast from wheel weights (80%) and Linotype (20%), about 15-18BHN. I use SR4756 for it in 357mag.

I really like the Accurate Arms powders. I use a lot of AA#2 and AA#9. I use AA#5 and AA#7 in 9mm with great results.

I guess there is one other thing. Felt recoil. Physics being what it is, the powder that gives you the highest velocity with the least amount of charge weight will usually give you the least amount of it too.


FWIW

 

[Wheelgunner840]

Howdy Skip.
As always, thanks for your input.

I don't have a way to measure the hardness of these bullets, but it does say "super hard cast" on the box. I have plenty of softer bullets already loaded at lower CAS velocities that I use for CAS and to train new shooters. I do not have a problem with beefing up the load with these bullets, but the AA powder data lists a max of 1272 fps with pressures of 42,600 CUP using the AA#5. The jacketed bullets (HDY HP/XTP) max out at 1462 fps with 43,500 CUP listed. This is AA powders data. I don't think 1800 fps can be done safely with these powders. Not even with #9. I might get those velocities with a carbine or rifle, but not out of a 4" bbl. GP-100.

The data states 1350 fps as max for the 158 gr. LSWC using #9. That's about as fast as the AA data suggests. I think, based on what you have said about the super hard cast LSWCs, that I will use the #7 for those and push them to 1250-1300 fps. That should be plenty fast enough for them to expand a bit, no? I will make up a dozen test rounds, and see how they do.

I really need to buy another .357. My Ruger has been the test gun for thousands of loads. I think a 6" bbl. would be a better testing platform than the 4" bbl. Sounds like a good excuse to buy another 586 or model 27!

WG840

 

[Paul5388]

WG,

I load .38 Specials almost to the velocities you're looking at. Of course, I shoot them in a .357 Mag, just for safety's sake.

The Lyman 358429, which weighs 168-170 gr, with 13.5 gr of 2400 in .38 Special brass in a 6" M28-2 clocks at 1270 fps MV. If I use 15.0 gr of 2400 in .357 brass with the same bullet, it clocks at 1420 fps MV.

.38 Specials in a 4" M66 with a 158 gr LSWC clock around 1170 fps using 8.0 gr of SR 4756. The same load clocks 1100 fps out of a 2" barrel.

When I shoot loads of this intensity, I always weigh each powder charge, so metering is a non-issue.

 

[Wheelgunner840]

Hi Paul.

I never load up .38 special brass on the hot side only because I have a couple of vintage .38 specials that I would not want to have hot loads mistakenly placed into.

What I am basically asking is if there is any noticeable difference with a loading traveling at 1200 fps when different powders are used. Unique, W-231, tite-group, AA #s 2,5,7,9, etc. can all be loaded to push a 158 gr. pill at that velocity.

What would make one choice better than another if the pressures are all about the same. Some are faster burning powders than others.

WG840

 

[n4zov]

I never load up .38 special brass on the hot side only because I have a couple of vintage .38 specials that I would not want to have hot loads mistakenly placed into them.

+1

 

[RidgwayCO]

When choosing among powders that basically produce the same velocity, I consider the following:

1) Faster powders generally burn more completely than slower powders.

2) Faster powders are generally more economical, in that less powder is required to accomplish the same task.

3) Faster powders might provide less recoil, as less powder is being burned (and the weight of the powder being burned is part of the recoil equation).

4) Faster powders generally have a higher peak pressure to accomplish the same velocity when compared to a slower powder.

Figure out your priorities, use the basic concepts above to fine tune your thinking, and then get busy reloading!

 

[OKFC05]

What RidgwayCO said.

Using slow powders at abnormally low pressures is seldom a good idea. There are several medium powders that are suitable for .38 and mid-range .357, with the choice coming down to personal preference. Save the slower powders for the higher powered .357 loads.

Curiosity question: Are you using a chronograph to measure velocities, or are you taking factory tables as gospel?

Only way to know what you are getting with your loads in your gun is to chronograph them. It seldom matches factory data unless they used a practically identical gun.

 

[Wheelgunner840]

Originally posted by OKFC05:
Curiosity question: Are you using a chronograph to measure velocities, or are you taking factory tables as gospel?

Only way to know what you are getting with your loads in your gun is to chronograph them. It seldom matches factory data unless they used a practically identical gun.

Yep. I run every new load over my own chrony. There is nothing worse than loading up a big ol' bunch of rds. that need to be pulled! I usually will make up a dozen or so, shoot them over the chrony and test for accuracy at the same time. My results almost never match the velocities listed in the manuals. But, they are surprisingly close to the on-line powder manufacturers results.

In general, I agree with using the faster powders VS the slower powders with a 158 gr. bullet. #5 and #7 are both medium fast - medium slow powders. From what smithcrazy suggested, it would seem best to push the S.Hard Cast bullets as fast as possible. Pretty much all the data books list 1100-1400 as maximum for the 158 grainer with a few exceptions.

The HDY 158 gr. HP/XTP will be loaded to factory velocities (1250fps). I can get this exact velocity with both powders (AA#5 and AA#7). The question remains, will it make any difference which one of the two powders I use?

I guess the same question applies to the SHC LSWCs. I was looking for a slightly milder load for these, but it was suggested that some severe leading may result if these are not pushed fairly fast. Both powders will achieve this as well.

What I am going to do is load up 12 rds. of each bullet type with both powders, and just shoot the darn things. I will report back if there is anything worth reporting. My guess is that I will not be able to tell which powder is in which case without looking at the label!

WG840

 

[Paul5388]

I never load up .38 special brass on the hot side only because I have a couple of vintage .38 specials that I would not want to have hot loads mistakenly placed into.

It's easy enough to load the same .38 Special OAL in .357 brass. However, I notice you're using ball powders, probably for metering purposes.

I got a "new" RCBS Uniflow today with the small drum on it. I'll check and see if Tite-Group, WSF and H110 actually meter good. The Bullseye I was "test driving" today was normally varying .06 gr, with an occasional charge that was .1 gr off of the 3.5 gr goal.

 

[jibjab]

I use AA#9 with 158-180gr for a 2.75" barreled .357 mag. I tried #7 but I only found accuracy at the low end with the heavier bullets, I choose to stay at or above 150gr with #9. I like AA#5 for lower end .357 mag with plated and semi-hard cast bullets. If I were to load 125-140gr I would lean towards something like #7, I say that because I have noticed significant lot to lot variances with this powder.
http://smith-wessonforum.com/eve/forums/a/tpc/f/570103904/m/8131096833

 

[Wheelgunner840]

Thanks for the info guys.

I will be testing a bunch of rounds this weekend. It's supposed to be a scorching 40 degrees hre on Saturday! I will be sure to post results.

WG840