Ok I have about 8lbs of 4756, a whole bunch of mag primers, and 150gr swc bullets. Any one have a good load?

Yes!

rsnyder, You got that response because the subject has been covered extensively last year, sometimes with some heated language.
Do a search for "the load" and there should be some EXCELLENT discussion on this powder in the 38/357.

Actually, I think "the Load" was dealing almost exclusively with .38 Special loads using SR 4756.

This is data from the 2nd edition, 1971, of Speer #8. It is normally an accepted practice to use the data for a heavier bullet of the same material/construction with a lighter bullet.



I would start low and work my way up, especially if I hadn't been using SR 4756 loads in my gun. Maybe something more along the lines of this DuPont data.

Now that's just mean.

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John

Got it! Thanks

Sorry, didn't mean to be.

In my opinion, SR4756 is one of the best powders for heavy 38spl and light 357mag loads available today. I use it under 160gr LSWC bullets made in my garage with great results. The 357mag loads are shot out of M586/M686 6" revolvers and a Marlin 1894CS carbine rifle.

My loads from the rifle get 1600fps while from the handgun they develop 1300fps. No leading and very consistent at these velocities.

(I hope this takes away the sharpness of my "mean" answer above! )

No worry's. I should have done a search first. Sr-4756 has served me well in my 40's and 44's. I just have a stockpile of CCI-550's and 148-150gr SWC's I feel I should turn into something?

The Speer data I posted is with a CCI500, not a 550. I don't know what DuPont used, but I would suspect it was a standard primer.

I have always used SR 4756 with light bullets, i.e. 125 gr, so I don't know that I've ever clocked it with a 168 gr Keith bullet. Maybe that's another project to put on my list.

The only Smith I ever wrecked was with SR4756. But likely it was just youthful exuberance. Perhaps wrecked is an overstatement. The cylinder opened with a medium sized mallet. Unfortunately, the mallet was not big enough to get the case out.....

Howard B Hmmmmm? what load and bullet?

I did have a chance to chrono some of the 4756 loads:

Using a 175 grain 358429 and 4756/8.0 grains with a Winchester SP primer from a 6" GP-100 gave 1185 fps. This was with the bullet crimped in the crimp groove for a 1.655" LOA.

Using a Hornady/Speer/S&W swaged 158 grain SWC-HP with 4756/6.8 grains and a Winchester SP Primer gave 1055 fps from a 7.5" Blackhawk. The LOA was 1.600"

Using the same combination as above but with 7.7 grains of 4756 gave 1200 fps.

One last comment, the last two loads, when using the Speer or S&W SWC-HPs, are wonderfully efficient killers of small game. They are not too loud and critters just topple over when hit. The S&Ws are no longer available and haven't been for a long time, but I have a lot of them loaded up from days past.

Edited to correct an oversight - all of the above loads were put up in .357 cases.

Hope this helps.

I just loaded 400-500 .38 Specials with 358429s and 6.3 gr of SR 4756. I thought they were pretty wimpy, but I haven't actually clocked them yet.

I've shot them out of a M14-2 and a 1949 M&P, but they didn't feel like they were even close to 5.5 gr of Unique with a 158 gr bullet.

I'm not sure I trust the #8 manual. 11.0 seems pretty heavy? I generally use 11.0 and a 240 swc in my 44's for punchin paper. While not hot its not wimpy either. Looks like somewhere around 9.0 will be my starting point. Thanks for all of the info. Bob

Bob,
Are you saying that you are going to use 9.0gr of SR4756 in a 357mag case with a 150gr LSWC for your load?

If so, I just want to let you know something. That is real close to the load I use for the ones described in my previous post.

One caution though, I had an older M586 6" that didn't like it. The cases didn't need pushed out with a tool BUT they didn't fall out either. Work your load up from 8.0gr would be my suggestion.

Mack,
I know you have been a big opponent of the Speer #8 and it's heavy 38spl loads. Then you post loads that are considerably higher than what Hodgdon posts on their website for near this weight bullet. Can you clarify please?

Their maximum load for a 158gr LSWC is 6.5gr of SR4756 for 1214fps. I agree with the data you have posted, don't get me wrong. It just seems to be closer to the Speer #8 than the Hodgdon data. Please explain.

I’ve done some chrono work with jacketed bullets over SR4756 in 38spl and 357mag; results are summed up in this chart.



Can’t agree more with Paul and Skip: starting low and watching out for pressure signs sounds like a very good idea. I’d consider starting much lower than 9.0 gr. – this charge is 2.5 gr. above current manufacturers’ recommendations... Here is what my primers looked like:



Note clear primer cratering in 10 gr. and 11 gr. charges. FWIW I am sticking with 9.5 gr. as my max charge for this load. Other powders out there will get me 1400 fps without setting any pressure records.

BTW, Paul, 6.3 gr. SR4756 under 158 gr. SJHP didn’t feel all that wimpy... in my S&W442

Mike

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9x19, 9x29R, 9x33R, 10x22

35 years ago one of my favorite accuracy loads was 7.5 4756 and a cast 158 swc in 38 spl cases. this is NOT for a 38 gun. if you want a stronger 38 case cut a 357 case in a trim die to 38 length , theres more metal in the web of the 357 case.

Skip,

I originally neglected to indicate that the loads in question were put up in .357 brass. That has been corrected. Sorry for the confusion.

BTW, did anyone notice the link that was posted here abouts a week or so back to the article by Alan Jones that appeared in the May issue of Shooting Times? In it Jones stated that the first Speer manual to have pressure tested data generated by a piezoelectric transducer was the #12 manual. It was a pretty hot topic here within the last six months or so that because Bill Caldwell had a piezoelecrtic transducer rig around 1970 that the data for the #8 manual had to have been (or alternatively, most likely had been) pressure tested. Jones stated that when they started on the #12 they used the crusher data from previous manuals as their starting point. This should clear up some of the confusion and add a little on its own. When you figure that the #12 had a publication date of 1994 and the first edition of the #8 had a publication date of 1970, that was a long time for Speer to get on the bandwagon. It opens the door to the question of when they got everything on to the crusher-based system.

In 1996, I spoke with Hodgdon and Nosler about two different issues. At Hodgdon's I spoke with Tom Shepard (sp?) who was the VP of Marketing. He told me that at that time Sierra had just gotten all the cartridges up and running on their pressure gun. And at Nosler one of their enginers told me that they were still using the tea leaves & snake oil approach (primer appearance and case head expansion) that the home reloader would use to develop loads for the less popular cartridges like the 6.5 x 55 Swede.

For what it is worth, gentlemen.

Mack,
I hate to belabor a point but; the data I posted IS FOR 357Mag from the Hodgdon data website!

Your post says "you had a chance to chronograph" some loads, I just naturally assumed that you had loaded them. If you did, they were over their suggested maximum load by almost 2gr!

The point I was speaking to was the great inconsistency in your opposition to the heavy 38spl loads of the #8 only to use them for the 357Mag, and they are WAY over their suggested load for that cartridge.

I, on the other hand, am quite consistent. I use the Speer #8, and I don't care that they used crusher data, for loading my 160gr LSWC, whether it is in long or short cases!

Minimum load in the 38spl with SR4756 and minimum load in the 357Mag with the same powder and bullet!

FWIW

I have to admit that I'm not loading many Speer #8 max loads of 4756 with 125 gr bullets any more. When I figured the difference in energy between the 125s (729 ft lbs) and a 168 gr SWC at 1400+ (752 ft lbs), I've pretty well converted to 168 gr. That's about 60% of the available energy of a 55 gr .223 at 3200 fps.

Skip,

I am sorry if I appear to be incosistent. I try not to be. The loads that I quoted were loaded by me using DuPont and later IMR data. As far as the current data that Hodgdon lists, I can't say that I ever saw it before. However, I try to collect every manual that becomes available, and have DuPont data back to 1975 and IMR data as recent as 2004. For going on the last 20 years, IMR, and DuPont before them, listed a max load for the 158 SWC at 7.7 grains of 4756 in the .357. That is what my 1990, 1998 and 2004 data sheets from IMR show.

I haven't spoken with anyone from Hodgdon, but from the data you are referring to it would appear that the data were recently (some time after 2004) re-shot using the conformal transducer set-up and hence the pressures are in PSI. The sole exception to this are the Trailboss data which are still in CUP. Go figure! Since the allowable pressures in the .357 are different depending on the measurement system (CUP vs PSI), that would explain the difference in the max loads. I would point out that Lyman still uses the CUP standard as well as Accurate Arms. Accurate Arms used the newer PSI standard for their data in their #1 Manual, but went back to the older CUP standard for their #2(Revised) manual. When they did so, the STARTING loads for the CUP data were the MAX loads from the PSI data. There is that much difference between the two standards for the .357.

So as near as I can tell, the loads that I provided velocity for are still within allowable pressures for the .357.

The DuPont data I posted on page 1 was from 1964 and it shows 9.5 gr as a max load with a 158 gr Lead bullet. It claims to be psi, but if it is actually cup, the pressure is 11,000 below max (either 45,000 or 46,000, depending on the source) for that time.

I think Mack is correct - reshoot was done between 2005 and 2007 editions of IMR. Here is 357mag page from 2005 manual:



and from IMR 2007 manual:



Mike

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9x19, 9x29R, 9x33R, 10x22

I'm not exactly sure of what I'm supposed to be seeing here.

There isn't very much of the data that correlates, due to using different bullets in the two sets. In one, they used a 158 gr Lead bullet at 7.7 gr and 35,800 cup (which is only 10,000 cup less than max), a 158 gr Rem SJHP at 7.5 gr and then omit the lead bullet and switch to a 158 gr XTP at 6.5 gr (that's 5,400 psi, 16+% less than max).

Paul,

The point was to support Mack's assertion that IMR transitioned from crusher to tranducer method after 2004.

Admittedly, I also think that recent manufacturers' data provides some helpful balance to the older manuals. People can play with the fire all they like. I do it myself and have no problem with it. But I don't want anyone who has less experience than a few of us here to look at my charts and think that all loads I tested are safely within modern reloading recommendations. They are not. "Closed course, professional driver, don't try it at home".

Mike

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9x19, 9x29R, 9x33R, 10x22

Mike,

I'm a firm supporter of people needing to be aware of what they're doing and the consequences of their actions. If they aren't willing to do that, they need to use only minimum loads from recent data, factory loads or single cock air guns.

I don't put warning labels on my reloads and for that matter, I don't know of anyone who does.