SR 4756 and Herco Powder

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I used to use IMR-4756 with mostly 357 mag loads. I still have a little left, it's on the slower side of average for a handgun powder. I have other powders I've mostly moved on to.
 
I used 4756 many years ago..
Pressures seemed abnormally high (flattened primers and difficult ejection in Mdl 66) in .357 loads and it is probably too slow for accurate .38 special loads. I switched to 2400 for .357 and never looked back....Most accurate load I have used for the .357 is 125gr MT Gold JHP and 14-14.5gr 2400.
.38 special, I like 231 and VV310....
Terry
 
I have several loads using SR4756 in both 38Spl and 357Mag. Both loads are from an older manual and would be considered unsafe by today's standards BUT, I know folks that have used them for years and years with no ill effect on their firearms.
The 38Spl will push a 158gr LSWC @ 1100fps from a 3" tube and the 357Mag will push a 158gr LSWC @ 1280fps from a 6" barrel and 1580 from a 20". The latter are loads I developed for my wife to shoot. One load for her M586 and Marlin 1894CS.

FWIW
I used Herco in some 45ACP but with today's data, all I got were little black dots all over my forearms! I have too many other powders to use and left that one on the shelf. :D
 
I started out with SR7625 for light loads and 2400 for heavy loads. 2400 burnt too dirty(unburnt powder) for me. Switched over to SR4756 and use it for 9mm,38sp,357m,40s&w,10mm,44m.
 
I used it for 38 and 357 loads with lead and jacket bullets. (SR4756)

It really sucked in my 38 spl. 1 7/8 inch snub nose except for a low velosity target load with the Mag-Tech 158gr LRN bullet.

It gave fair groups in the 686 6" with 38 brass but nothing that out grouped my other powders. It also worked better with the heavier bullets and 5.8grs of SR4756 with a cci500 primer got me a +P velosity.

With the Magnum loads light loads with a 110 jhp had a +/- 367 fps difference,probably due to the primer going across the top of the powder with the Hodgdon data.
the 125 Jhp shot better and a standard 1448fps can be attained with as little as 39fps ED's but pressure spikes happen at maximum loads and with primer changes, take care if using the cci550 primer,which is not needed for this powder.

the 158 XTP really worked well with this powder and I had no problem with my first try finding a fac dup of 1235fps with an ES of only 44 fps with a cci500 .

It is not mentioned in the manuals but I think a 60% case density w/bullet seated may be needed and a chrony sure helps out when you are getting near maximum loads. With its small size and density a little dab can make your scale move,big time so you need to weigh your loads,one of the pains with this powder, but it will deliver maximum velositys ,if thats what you want.

PS;
I have yet to find a manual with data that fits "Todays" SR 4756 per barrel length/fps that comes across my chrony at eight feet. Most max loads are standard 38 spl loads for the j frame except the new Lyman for 38,357,44&45 colt comes the closest to my test and readings.

Stay safe.
 
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started out on a tight budget now been reloading 25 yrs and back in the day got a canister of herco free and loaded my 357. 158 gr jhp with 6.5 grains stout but grouped well. I tried herco with cast bullets and leaded my barrel. Bulseye and 2400 are much better for the .357
 
I did forget to post that SR4756 is one of my favorites for the 40S&W! Lots of velocity, low pressure and that makes shooting them in a Glock, win/win.


1000fps from a 180gr is nothing to sneeze at!
 
Another powder that is close to Herco in the amount of powder and velosity is HS-6. If you look up the data other than the Hodgdon site you can see how close they can be.

I noticed this the other day when looking up 9mm data.......
 
Another powder that is close to Herco in the amount of powder and velosity is HS-6...

That's interesting. I had never given that any thought but years ago I used to use Herco in 9mm. I changed to HS6 because Herco is so bulky that it is hard to load in 9x19. HS6 has always worked great for me.

Back then I used Herco in shotguns and some other pistol loads, mostly in .357s and 44 Magnums (target loads), because I could get it at good prices, but those days are gone. (same with Red Dot and Green Dot)

Never did see good prices on the Dupont powders (SR4756) like I did on the old Hercules powders, so they didn't get much of my attention, except in rifle loads.
 
About the only IMR and Alliant powders that I have yet to try is Herco and 2400.

I "Sort of" used HS6 & HS7, back in the day but it was known then as w540 and w571.............

I will try 2400 powder first............. for my 357.

Here is a target back in 2008 with (HS-7) w571 when I still had some,with the old M19 6" at 25 yards,when my eyes were good and my hands did not shake, with 12 shots.
2hn255f.jpg


SR4756 last Fall with a snub nose J frame

1z5keq8.jpg
 
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