IMR 4756 and IMR 4759 - What are they good for?

[kelbro]

I found unopened pounds of both of these powders in my cabinet. I can't, for the life of me, remember what I bought them for.

I'm sure that it was something that I read on here or THR that prompted the purchase.

Can anybody shed some light on their uses of either or both of these powders?

Thanks

[possom813]

4756

http://castboolits.gunloads.com/showthread.php?62158-IMR-SR-4756-and-cast-boolits



4759

http://castboolits.gunloads.com/showthread.php?120045-SR-4759-List-your-reloads-here

[Shiloh]

4759 in .30 cal with cast, 8mm with cast. Many, many, calibers for cast.

Shiloh

[rintinglen]

4759 is a great cast powder for reduced rifle loads. The story I heard was that during WWII the Army needed to test penetration at long range, but wanted a powder that would let them shoot at shorter range with reduced velocity. Dupont came through with IMR 4759. After the war, cast boolit shooters discovered its usefulness for service caliber rifle rounds and cast boolits. 17.5 grains with a 311-041 is quite accurate in a 30-30.

4756 is a shotgun/pistol powder, very slightly slower than Unique, a tad faster than Herco, with similar applications. Unique data can be used,but Lyman's 3rd Edition Handbook has many loads listed for large caliber Handgun cartridges, as well as some low velocity rifle rounds. I have never used this powder, so I have no knowledge on how well it works.

[kelbro]

Thanks for the input and the links. Appreciate it.

[44man]

4759 might be the most useful powder ever. Bulky to fill the case better, a perfect burn rate, clean burning.
I use it in the 7R and it should be perfect in the 7 Waters, 7BR, 45-70 and reduced loads in rifles.
It is a pain in a measure so I weigh every charge but it is worth it for the superb accuracy.
It is hard to find loads for with many calibers but it works with about anything.

[Shuz]

I've used 4759 in a lotta rifles with cast boolits. It performs very well, but it meters lousy to the extent that I have to weigh every charge. Since I load mostly on a Dillon 450 for my rifles, I've switched to Rel 7 for cast in my 450. I presently have a new unopened 5 lb can of Dupont SR 4759 that I would gladly swap for 5 lbs of Rel 7 to someone in the Spokane Wa. North Idaho areas in a FTF transaction.

[runfiverun]

4756 is a very good magnum type shot shell powder.
it also works very well in the 45 colt with jaxketed and cast boolits.
there are a few mule deer in this area that have met their demise from the 45 colt with this powder.
it is super quiet in the lever gun too.

[DLCTEX]

4759 is my favorite powder for 45-70 and 4756 is, as stated a great pistol powder as well as shot shell.

[EDG]

I wholeheartedly agree. I use lots of it in cast bullet loads for 38-55, 40-65 and 45-70.
The coarse grains do not bother me. I use a Lyman Autoscale to dispense extruded powders and it works great with this powder.


4759 might be the most useful powder ever. Bulky to fill the case better, a perfect burn rate, clean burning.
I use it in the 7R and it should be perfect in the 7 Waters, 7BR, 45-70 and reduced loads in rifles.
It is a pain in a measure so I weigh every charge but it is worth it for the superb accuracy.
It is hard to find loads for with many calibers but it works with about anything.

[Harry O]

I have not used the 4759. However, I use 4756 in most of my 32-20 handgun loads. It is a stiffer load than factory loads, but I only use it in strong guns. It is the most accurate 32-20 handgun load I have ever tried, and I have been shooting and reloading that caliber for almost 50 years.

I have tried it in several other calibers (.32 Magnum, 9mm Luger, .38 Special and .357 Magnum) and it does pretty good in all of them, but I have found other powders do better in each of them -- pretty much a different powder for each one.

[Green Lizzard]

i have used sr4759 in 22 hornet 45-70 and every thing in between it works great but meters bad,lots of data in old belding and mull manual

[357Mag]

Kel -

Howdy !

7.0gr IMR 4756 under 158SCW in .357Mag is one of Skeeter Skelton's old-tymee loads. On the few instances I depart from my steady use
of 14.5gr WW296 and SP Mag primer w/ Lyman 158 - 172gr SWC...... I use the 7.0 gr 4756 load. It's a bit sooty, but is hyper-accurate.
I used it some in 16ga, under 1 1/8oz 6's or 7.5s. Worked mighty well on nuisance birds.

IMR4759 continues to amaze in my Marlin M-336 XLR .35 Rem. 18.7gr and CCI SR's under surplus Rem 150PSP " J-words " have gone
5-shots @ 100 into 5/8", one group w/ 3-shots into .250" @ 100.


With regards,
357Mag











I found unopened pounds of both of these powders in my cabinet. I can't, for the life of me, remember what I bought them for.

I'm sure that it was something that I read on here or THR that prompted the purchase.

Can anybody shed some light on their uses of either or both of these powders?

Thanks

[bbqncigars]

The only thing I have against 4759 is that it seems engineered to bridge. The B&M measure is the only thing that will throw steady charges of this/

[snuffy]

4759 is made of hollow sticks. That's why it's so bulky. Looks like what you get when you strip a wire, sorta like a hollow piece of spaghetti. Just a side note to explain how it bulks up so well.

I bought some of it as a surplus powder, IIRC it was a 5 pound jug. It shoots great in my 45/70 NEF buff classic.

4756 is a great powder for most straight walled handgun loads. IMR is real proud of it though, so up-front cost is a consideration. I got a 5 pound can of it for loading steel shotgun loads for duck/geese. Since I have no plans to ever hunt waterfowl again, and there's Alliant "steel" powder that's way better, I used it up loading 40 S&W loads with extreme's plated 165's. Yeah, right about 4#'s of it! IDPA, IPSC, and plinking use a bunch of powder.

[rupe01]

lots of data in old belding and mull manual

Many thanks indeed for that info Green Lizzard! I had not heard of or seen that old manual before. I have since found a free PDF download of it and added it to my library. Lots of great data, thanks!

[selmerfan]

Hmm, I only knew 4756 to be a good magnum shotgun powder - I've got a couple pounds on my shelf for some reason. More cast boolit fodder!!!

[Shiloh]

4759 is GREAT for cast boolits in my .30 cal rifle loads.

Shiloh

[bruce drake]

IMR SR4759 is just a touch slower than H110 according to my Sierra burn chart. Has any one used it in a 300 Blackout chambered AR?

[Screwbolts]

4759 is also one of the best powders for "SMOKELESS" built Muzzle loaders. It is one of the powders that was designed to burn/ignite, well/completely in low pressure loadings.

Ken

[randyrat]

IMR 4756 (mine was in a lime green can)
Was one of the best powders I have used for the 40 cal...I got the velocity with lower pressures

[Freischütz]

SR4756 is the powder Speer 8 used for many of their super heavy loads.

[krems]

I've settled on 4756 for most of my "fun" handgun loads. I use it in the 500 Linebaugh, 45 colt, 44 magnum, and 500 S&W. It burns clean, meters good, and takes up some case capacity. I like it because if I was to double charge a case I couldn't seat the bullet in the case. For my "top end loads" I still use 2400 and ww296.

Krems

[Lead Fred]

I like 4756 for the 45 ACP as a back up powder, it works well in the 45/70
My reloading bag carries the one can I have left, so I can do both calibers out of one bag

[35 shooter]

4759 works well in 35 whelen with a filler to take up air space for reduced and not so reduced loads with cast.

[mrvmax]

4759 works well in my K31 loads

[JeffinNZ]

IMR SR4759 is just a touch slower than H110 according to my Sierra burn chart. Has any one used it in a 300 Blackout chambered AR?

Would SR4759 be a bit 'chunky' to get a full charge in a 300 Blackout?

[bruce drake]

Jeff,

I'm hoping it will work. You'd think I was in a Socialist State with the difficult I'm having finding new powder here in Indiana!

project is a long term one. Either I go out and shoot up some 300BLK that's already loaded for the cases or I sit down and cut and form more for this ladder test.

Bruce

[DANIEL07]

DOES ANY ONE HAVE ANY IMR 4759 SR FOR SALE ? PLEASE CONTACT daniel07@sbcglobal.net THANKS DANIEL07

[Kosh75287]

I think IMR-4756 was all the rage among the .38 Super "Major" reloaders for a while. I think it was overshadowed by newer propellants that would do such things just a little bit better.

I recall IMR-4759 getting mentioned most often in connection with cartridges originally loaded with black powder, and with reduced loads in military rifle calibers. The few folks I know of who use it tend to swear by it.

[sandman228]

ive never used 4759 . but I do like 4756 in 45 colt loads with a 200 gr swc bullet ,you have to stay above min charge and use a heavy crimp.

[snuffy]

DOES ANY ONE HAVE ANY IMR 4759 SR FOR SALE ? PLEASE CONTACT daniel07@sbcglobal.net THANKS DANIEL07

You do know that those two powders are no longer made? IIRC it was 2-3 years ago that they announced they were discontinuing SR 4756, PB, SR-IMR 4759, and one other that I can't recall. The machines used to make those old DuPont powders were worn out, needed to be replaced. Their bean counters told them those powders weren't selling well. We love our computers for the info we can trade on forums like this, but when used to show sales trends of what powders aren't selling well, we end up losing some of our favorite powders.

Also your only hope of finding some of those old powders is to go into a well established gunshop that has some way back on a dusty shelf. Meaning some old crusty individual smoking a cigar or pipe. He'll gladly sell you the powder, but then launch into tales of how he may have used some of it way back in the 60's.

If only we could sell powder simply by packing it up in a solid box, sending it to whoever. I would gladly sell what I have, but I don't know of anybody locally that has the proper permits to send haz-mat materials.

4759 was discontinued 2-3 times back in the 70's and 80's. DuPont got tons of letters from the shutzen crowd to please bring it back. They responded by making another run of the powder, only to quit again. The stuff I have is marked pull-down, it came from Jeff Bartlet the online surplus dealer. I have no clue what cartridges were loaded with this powder that were pulled down. But I did a test loading 45-70 shells with a small amount of canister 4759 that I had left, and the pull down powder with everything the same except the two powders. Shot over my chrono and at a target, they were identical as to velocity and group size.

[DANIEL07]

i think imr-4756 was all the rage among the .38 super "major" reloaders for a while. I think it was overshadowed by newer propellants that would do such things just a little bit better.

I recall imr-4759 getting mentioned most often in connection with cartridges originally loaded with black powder, and with reduced loads in military rifle calibers. The few folks i know of who use it tend to swear by it.

thank you for your info , we had some imr-4759. It is and was the best powder we have used in the new modern savage muzzle loaders ,we have about ten of these new guns in are deer hunting group they shoot very tight and accurate with this powder. We also swear by it. Just can't find any of it for now ,i will try and look for some in old gun stores, might get lucky ,thanks daniel07

[Digital Dan]

DOES ANY ONE HAVE ANY IMR 4759 SR FOR SALE ? PLEASE CONTACT daniel07@sbcglobal.net THANKS DANIEL07

Would depend on whether you're within driving distance of Tampa, FL and how much you want it. I have ample supply.