IMR 4759

[savagebeast]

Picked up some IMR 4759 last week. I'm making the switch from AA-5744 whick I always measured out using Lee Dippers. If I'm reading the sliding chart provided by Lee correctly It looks as though the largest Dipper in the set (4.3) will only give me 43grains of powder. So if this is correct I guess I will need a scale. Any recommendations or thoughts. I will be shooting only 300gr bullets.

[rbinar]

Apr 7, 2009 11:36:43 GMT -5 savagebeast said:

Picked up some IMR 4759 last week. I'm making the switch from AA-5744 whick I always measured out using Lee Dippers. If I'm reading the sliding chart provided by Lee correctly It looks as though the largest Dipper in the set (4.3) will only give me 43grains of powder. So if this is correct I guess I will need a scale. Any recommendations or thoughts. I will be shooting only 300gr bullets.

I used my 4.3 grain dipper and got more like 48 grains of powder.

I don't think you want to use that much of this powder it will likely blow sabots

[jims]

43 grains was a good, reliable powder for me with the 300 grain bullets in the .50. I unfortunately had a mistaken double load of it in my .38 with about the same bullet weight and it turned out to be quite an explosive , damaging proposition. RB is correct, if you get beyond the book loads I have found accuracy to drop off pretty quickly.
A good beam scale can be had for a modest sum and is a worthwhile investment I feel. You really know what charge you have then and can make minor adjustments easily.

[raf]

43 grains plus or minus 1 grain should be pretty good. You'll have to experiment to see what your rifle likes.

[zing]

yes also interested on the views of other people related to this. i shoot 4759 42 grains, 250 sst bullet, gun seems to like that load, zeroed with good groupings at150 yds, 6" of drop at 200 yds, from asking and looking throug the site seems that am shooting around 2100-2200 fps, want to move up to maby 43 grs again to get a little bit more speed. anybody know what kind of velocity i can obtain by that charge and using a mmp hph12 sabot.

thanks

[Dave W]

Approx. an additional 25fps for the extra grain of powder.

[ET]

Apr 7, 2009 17:30:51 GMT -5 zing said:

yes also interested on the views of other people related to this. i shoot 4759 42 grains, 250 sst bullet, gun seems to like that load, zeroed with good groupings at150 yds, 6" of drop at 200 yds, from asking and looking throug the site seems that am shooting around 2100-2200 fps, want to move up to maby 43 grs again to get a little bit more speed. anybody know what kind of velocity i can obtain by that charge and using a mmp hph12 sabot.

thanks

Zing

To get a proper velocity reading you actually need a chronograph to verify what it is.
For my 10ML-II (tight bore) using 43 grains of IMR-4759 (1/2lb can) with HPH-24 sabot, 250SST/SW and Cheddite primer with a regular breech plug I would get around 2320-fps.
Zeroed for 150-yds I would hit 4-1/2” to 4-3/4” low at 200-yds. In my manual for the pre-Accu Trigger model the recommended load for 250/300gr bullets was 43gr., plus or minus 2gr.

Hope this is helpful.

Ed

[zing]

thanks, now i guess the question is will she like it!!

[ET]

Mine loves it at 43grs of 4759.
It is my most acuurate load found so far for my 10ML-II and haven't strayed from it yet.

Ed

[dougedwards]

Apr 7, 2009 17:30:51 GMT -5 zing said:

yes also interested on the views of other people related to this. i shoot 4759 42 grains, 250 sst bullet, gun seems to like that load, zeroed with good groupings at150 yds, 6" of drop at 200 yds, from asking and looking throug the site seems that am shooting around 2100-2200 fps, want to move up to maby 43 grs again to get a little bit more speed. anybody know what kind of velocity i can obtain by that charge and using a mmp hph12 sabot.

thanks

Part of the problem with trying to shoot fast with this powder is the advent of sabot disruption especially shooting when the barrel is hot. 4759 is a very accurate powder in many 50 caliber rifles with either 250 or 300 grain bullets. You have the option of memorizing bullet drop referring to distances and bullet weight (some have it pasted to the stock) or you can opt to go with slower burning powders such as H4198 or Reloader7 if speed is your goal. But shooting fast is hardly and advantage if accuracy suffers. We all have comprimises to make. Many have found accuracy and speed can go hand in hand but you will not discover that in your gun until you experiment a little. I am guessing that moving up 1 grain 4759 with a 300 grain bullet might get you 25fps or so but nothing that will make an appreciable difference in your drop from 150 to 200 yards.

Doug

[savedbyjc7]

4.0 DIPPER GIVES ME 44 GRAINS. THATS POURED ON A DIGITAL SCALE.

[zing]

yes igree totally douge, with what ur saying, i would never want to compromise speed for my accuracy, but if i can gain a little less drop at the 200 yd mark by going up one grain and not kill my accuracy i would, it should helpa little bit with bullet drop beyond 200yds, wouldn't it?? in turn i was thinking og trying the HPH12 sabots(?) to help keep the grouping as tight and consistent as i can, would this be the case with that sabot? thanks to all for the input. Also SORRY to savagebeast by taking his thread kinda off topic!!!!!

[savagebeast]

Thanks for all the input guy's. I plan on ordering a scale to keep things as accurate as possible and will start with 43 grains.

[smitty]

In the past I used 4759 powder and got very good accuracy in the 41-43 range with 300gr bullets. But I am very curious if any of the long time users of this powder have noticed the POI changing depending on outside temps? Last fall I ran into an issue where I zeroed one of my guns at 100 yrds on a day when it was in the 70's. Well a couple weeks later when the temps were in the 40's my POI changed to 4-5" low at 100yrd ? Since it was now hunting season I just adjusted the scope and then fired several shots to confirmed the zero at 100 again. Was fortunate to take several deer that year but noticed my hits on the deer were higher on warm days but on cool days they were exactly where I was holding and aiming ? So after the season I shot this gun and same load several times on cold days and she was always dead on at 100 but when I shot it again on a spring day in the upper 60's my POI was 5" high ? Although I have never seen anyone else mention this about IMR 4759 I know I'm not crazy because a friends Savage shooting this same load did the exact same thing to him ? It really makes me wonder if the powder is temp sensitive ?

smitty

[Dave W]

Apr 8, 2009 16:39:29 GMT -5 smitty said:

In the past I used 4759 powder and got very good accuracy in the 41-43 range with 300gr bullets. But I am very curious if any of the long time users of this powder have noticed the POI changing depending on outside temps? Last fall I ran into an issue where I zeroed one of my guns at 100 yrds on a day when it was in the 70's. Well a couple weeks later when the temps were in the 40's my POI changed to 4-5" low at 100yrd ? Since it was now hunting season I just adjusted the scope and then fired several shots to confirmed the zero at 100 again. Was fortunate to take several deer that year but noticed my hits on the deer were higher on warm days but on cool days they were exactly where I was holding and aiming ? So after the season I shot this gun and same load several times on cold days and she was always dead on at 100 but when I shot it again on a spring day in the upper 60's my POI was 5" high ? Although I have never seen anyone else mention this about IMR 4759 I know I'm not crazy because a friends Savage shooting this same load did the exact same thing to him ? It really makes me wonder if the powder is temp sensitive ?

smitty

I know when I have timed the 300 Rem with 42gr it is always approx. 2000fps, never paid attention to POI since this was a plinking load. You are apparently not the first to have this kind of problem.
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