WW 748 in the M1-A

[Treetop]

I did a search and found lots of data on WW 748 and the .30-30, but I can't seem to find any data for the 7.62x51. The reason I ask is I have about 10-12 lbs left over from my J word/NRA high power days. If it's safe, reasonably accurate and functions the rifle, I would like to shoot it up. I have several moulds available: Lee 155, Lyman 31141, 311291, and the 311332.

The Lyman manual lists it for several bullets that I cast for, but I would really like to start with the Lee 155 grain. Any suggestions for a safe starting load? I'm guessing around 35 grains... Thanks,

[Larry Gibson]

Treetop

Being a ball type powder it will have some ignition issues at the lower pressure of most cast bullet loads. It works well in the 30-30 because it is near 100% loading density with 170+ gr cast bullets and those loads are still within pressure limits for the 30-30. However to achieve reasonable cast bullet velocities that are accurate in your M1A requires a reduced load. This may be below the efficient burning pressure area for 748. With the lighter Lee 155 bullet your velocities may well be too high for accuracy before the pressure is sufficient for efficient burning of the 748. If I was prone to try 748 in an M1A or any .308W for that matter I would try it with 311291 or 311332, the two heavier bullets. Preferably I would try it with 311299, a heavier yet bullet and my choice for cast bullet loads in my M1A.

Acceptable accuracy with cast bullets in an M1A can be had with velocities in the 1800 - 2100 fps range. It depends on the twist of the barrel. Best accuracy at the higher velocity will be with the 12" twist barrel. You might want to check out BruceBs thread on his loading for the M1A. Lots of good information there, might save you some frustration if you read that thread first.

Larry Gibson

[Treetop]

Larry, thanks for your timely and informative reply. I had read BruceB's excellent sticky several times prior to posting my question RE: WW 748. In fact, BruceB not mentioning WW 748 was why I posted up, I was hoping against hope that 748 had just been overlooked, but I suspected that there may be ignition problems in a "less than full" case.

I can always sell or trade the WW 748 for something more appropriate for cast boolits.

Larry, what are some of YOUR favorite powders for 170-200 grain boolits in the M1-A? Thanks,

[BruceB]

Thanks for the kind words!

The only reason that 748 wasn't tried in my M1A is that I don't have any of the stuff. H335 works well in the small number of loads in which I used it. I think Larry is correct about trying 748 with bullets on the heavy end of the range, and I believe it'll probably work just fine.

My results have been pretty decent with bullets from 150 grains on up, but in your case I'd get some workable loads with the heavier ones first, and then maybe experiment. Last weekend I fired a (very) short match with the 152-grain 311466, and made five consecutive hits on a 14"x16" plate at 415 yards, using the iron sights. With 100% semi-auto function and over 1900 fps at the muzzle, that isn't too shabby. The powder was XMP 5744, and that still amazes me.

That M1A project is calling to me again. There are still umpteen variables left to try. I have very high regard for the rifle.

I wish I had 10 pounds of 748. I've been trying to cut back on the number of powder types I own, but I'm still using about 25 or 30 different ones!

[rvpilot76]

This is my preliminary findings so far with the RCBS-308-200-SIL (215 grains with quenched WW alloy) and Ramshot TAC (4895 burn rate in ball powder form) in my Springfield MIA Loaded stainless. It has a 1-11" twist rate. I have just started working up a load for this rifle (the first so far-no jacketed down the tube), and while 30 grains just barely cycles the action (not reliably), 31 does so quite well. I have a highly accessorized M1A, and the modifiations done to the operating system include a NM TiN coated gas piston (non-grooved) from Sadlak Industries, and a NM spring guide, also from Sadlak. I have not upgraded the op-rod spring. Accuracy with this load is not where I would like, but I wouldn't expect it to be with such a small powder charge. I will be increasing the charge in .5 grain increments until the accuracy comes in, and I'll utilize my newly acquired CED M2 chronograph to track the velocity with each batch. I'll keep 'yall informed of the progress.

Kevin

[Larry Gibson]

rvpilot76

I will offer one suggestion; back off to 30 gr again and use a 1/2 gr dacron filler. Pay particular note to the ES (Extreme Spread) when using the chronograph. An ES of 50 fps or less is very good with a 10 shot test string. The SD (standard Deviation) in fps for a good load should fall within 25-40% of the the ES. Please do keep us informed.

Larry Gibson

[Treetop]

Thanks for the replies. My Lyman 311332 boolits, cast of wheel weights, lubed and gas checked weigh around 194-195 grains. I'm thinking of a starting load in the 30-32 grain range using WW 748. Does that sound reasonable?

[Larry Gibson]

Larry, thanks for your timely and informative reply. I had read BruceB's excellent sticky several times prior to posting my question RE: WW 748. In fact, BruceB not mentioning WW 748 was why I posted up, I was hoping against hope that 748 had just been overlooked, but I suspected that there may be ignition problems in a "less than full" case.

I can always sell or trade the WW 748 for something more appropriate for cast boolits.

Larry, what are some of YOUR favorite powders for 170-200 grain boolits in the M1-A? Thanks,

Treetop

I currently have 2 M1As; a rack grade with a milsurp 12" twist barrel and a full blown Fulton with a 11" twist Kreiger barrel with all the trimmings. That rifle is on it's 3rd barrel, is moa capable and got me to Master Class some years back shooting the NMC over an actual ourse and not a reduced one. I also made Master Class shooting long range (600 to 1000 yards) with it. Over the years I also have had several other M1As and M14s available when I was in the NG/USAR.

I have always found 4895 (any flavor) with a 1/2 gr dacron filler to be a very good powder in the M1A with 177 gr (311291) or the heavier 200 gr 311299. RL19 and H4831SC also give good service with the 311299.

Lately I've been trying 311466, as I see Bruce is also, in the rack grade with it's 12" twist. 4895 is working out well with it. I am looking at developing a load the equals M80 (US, not some of the very poor foreign M80) accuracy of 3 moa +/- at 23-2400 fps with linear dispersion as the range increases. If I get there with consistancy that should make a decent "combat" load for out to 400 yards.

Larry Gibson

Attached photo was taken a few years back at Yakima Training Center. I've a M14A1 and am preparing to give maneuver support to the 2 M60s (sitting behind the concertina wire) during a live fire exercise. We did that in SF without all the cemented in tripods etc. Needless to say the ammo was issue and not loaded with cast bullets. It was a good time, especially at night with several mags full of tracers.

[Mugs]

*I.ve shot alot of 7 BR with a 170 grn. cast and 1/2 grn. dacron with 25.5 grns. 748 with excellent results.
Mugs
IHMSA 5940L

[BarryinIN]

I've never used W748 with cast boolits, but used it in my M1A when I started shooting Highpower.
The American Rifleman ran an article called "The Service Rifle Powder Alternative" a little before I started HP, and the subject of the article was using W748 instead of the popular IMR4895. Since I liked the way ball powder flowed, that article was all I needed to convince me to try 748 when I started shooting HP.
I worked up a load with 748 that shot OK in my M1A and didn't mess with trying anything else.

I found it left a lot of residue or fouling in the barrel if I shot it enough. It just took me a while to know that.
I would usually clean the rifle after a practice session (80 to 100 rds). I'd run a wet patch or two down the bore, then brush it some. After the first couple of passes, the brush strokes got progressively easier until after maybe four-to-five strokes when it stabilized and felt the same each time. Any patches I'd run through after bore brushing would push down the bore easier than the first one did. Apparently, I was getting some fouling out when I brushed.

I wasn't used to firing that many rounds between cleanings in a centerfire rifle before, so having nothing to compare it to, I thought that was just how it was after that number of shots regardless of the powder used. I wondered if the feeling was caused by the bore brush wearing in use, but that wasn't it since I could re-use the brush next time and it would do the same thing.

Then I tried some IMR 4895 when I was out of 748. I had none of that fouling when I cleaned it. The first patch through the bore felt like the last patch. Same with the brush passes. There was none of that feeling like I was loosening up some crud at the start.
Hmmmm.
Now I knew that it was only doing it with one powder- the 748. This definitely eliminated the possibility of the bore brush wearing down (or a rough bore), because changing powders wouldn't have mattered.

Also- I was always getting unexplained flyers in slow-fire prone, but that dropped way down after the switch. I had been blaming those on myself, since slow prone was the last stage I'd shoot I just thought my eyesight was fading by the time I shot it. I still had my share of bad shots, but the difference was I didn't have the unexplained ones.
Adding two and two together, I decided the 748 must have left fouling in the barrel, and it accumulated to the point it had an affect on accuracy late in a match or practice session.

I've heard others talk of 748 bore fouling after enough shots, but it was after I had to find it out on my own. Too bad it took me so long to hear that. Had I not ran out of it and needed to use something else, I may not have found out when I did.
I didn't know enough then to know it wasn't typical.

It's too bad, because it shot well for me for the first few dozen rounds. I think it is a great powder if you can clean more often than I could then. I just had to quit using it in Highpower. A Highpower match might be 80 rounds plus sighters, and there is no way I could have cleaned during a match.
I like it in the .223, and have used it in other calibers since then, but I stopped using it in anything where I had to have good accuracy over a loooong string of shots.

One thing I should add: Powders change. This I've just described happened across 1989-91, so 20 years have passed since it started. They could have made a change to W748 several years ago so I might not have any such trouble now.