IMR sr 4759 ?

[joneb]

I have a lb of this powder, I am hoping it will be suitable for 7.62x39R with .311 123gr Xtreme plated FP at around 2000 fps.
I am also hoping for success with Xtreme's 150gr .308 FP for 30-30 Win and .308 Win with this powder and these plated bullets. Any advise will be appreciated.
Thanks
I am not able to find much load data regarding this powder.

 

[LAGS]

I use that SR 4759 for my cast bullet loads in a lot of calibers like the .308, 7.62x54, .303 amd 8mm Mauser
I have never tried to find data for it for Jacketed bullets.

 

[John C]

Check out the Lyman Cast Bullet Handbook, 4th Ed. It shows data for SR 4759 in all the calibers and weights (well, not exactly for 7.62x39, but they show data for 115 gr and 130 gr.....you should be able to back into data easily) and speeds you're looking for.

4759 is a great powder. Too bad they're discontinuing it by year's end. If I didn't have so much 5744, I'd probably pick up an 8 lb jug of it.

-John

 

[John C]

LAGS;

Jacketed data is harder to find. The Speer manuals have low velocity data showing 4759.

joneb is loading plated bullets. As I understand it, plated bullets require high end cast bullet data, or mid-to-low range of jacketed data. Presumably, the Lyman Cast Bullet Handbook data will work.

-John

 

[joneb]

I downloaded and perused Lymans 48th, it offered some insight about my questions. Thanks guys and keep it comin.

 

[LAGS]

I too have used th Cast Bullet Data for my Plated bullet loads and it worked very well.
Discontinuing SR4759 ?
Well it is back to IMR- 4198 for my cast loads.
I will see if I can find some SR 4759 before it is gone.
Thanks for the heads up.

 

[Walkalong]

It should work, as would AA5744. (I also have some old (Metal can) SR4759), as well as new 5744. (5744 works great for .45-70ish levels in .458 Win Mag.)

Those bullets will do well unless you try to drive them over around 2000 FPS. Depends on the bore etc.

I have some X-Treme in 123 Gr 7.62X39 and 150 .308. I drove the 123s to around 2200 and they shot terribly. I haven't yet tried them slower. I ran the 150s at around 1850 and they shot decently. I am going to bump them up a hair and see how they do. Both were shot in 300 BLK. (The 123 Gr is .311 or .312, so if you try it in a 30 caliber make sure you have enough neck clearance!) My gun likes the .310 Z Max so I am not sure if the diameter of the plated X-Treme was a role in the poor accuracy or just the speed. I think it was the speed.

 

[UziLand]

If you are using the xtreme 7.62x39 in a gas gun check your COAL after fireing 2 or three rounds. Those bullets are really short and the ones I got had no c-groove. I've had them
pop out of the case on the third round a couple of times. Yes I maxed crimped them.

 

[Walkalong]

More crimp on a plated bullet with poor neck tension won't help, and could hurt. Might ruin accuracy as well.

Check your neck tension.

 

[joneb]

I loaded up 30 rounds of 7.62x39R
Case, R-P small primer, trimmed to 1.52"
Primer, WSR
Bullet, Extreme 123gr plated FP
Powder IMR sr 4759
COL 2.05 which was to long I will try 1.95-2.00" on the next batch. I did not read my dummy round correctly
I loaded ten of each. 16gr, 16.5 and 17gr. The 16 and 16.5gr loads did not fully cycle while the 17gr load did. With a shorter COL on the next batch I will start at 17gr. There were no signs of copper plating in the bore, I used RCBS dies with a medium crimp? the COL did not change with cycled rounds.
I am very optimistic about finding a good load with this bullet powder combo, the thought of shooting a SKS and finding the brass and finding it undamaged appeals to me.
Next I will test for accuracy and then do a chrono check.
Thanks again,
joneb