ken fowler
Regular
- Location
- Sarnia Ontario
sold
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748 win info for a 270
- Thread starter ken fowler
- Start date
I've owned and still have several 270 Win rifles and 748 was not a powder I would choose to use for reloading. IMO it is a bit too fast burning to be optimal. I just took a look at an old Winchester manual and it doesn't list a load with 748.
I found one load, for a cast bullet in Lyman 46.
I replied because I also had a couple of pounds of 748, traded it off at a gun show, just to get rid of it. It has some applications where it shines, but 748 is not what I'd call a universal powder.
I found one load, for a cast bullet in Lyman 46.
I replied because I also had a couple of pounds of 748, traded it off at a gun show, just to get rid of it. It has some applications where it shines, but 748 is not what I'd call a universal powder.
- Location
- Somewhere on the Hudson Bay Coast
Just because you've got lots of 748 doesn't mean its a suitable powder for the .270. Even with light bullets, most published powder recommendations call for 760 or slower. I did come across .270/748 data for use with 125 gr cast bullets, but if you were to use it with jacketed bullets, the velocities you achieved before seeing pressure signs wouldn't be typical of .270 performance. If you ignore the pressure signs in attempt to gain typical velocity, you won't have a good day. I did find some .270 load data for H-335, which has similar properties to W-748, but I'll stop short of saying the data is interchangeable in all applications. According to the Hodgdon site, H-335 data is only suitable for light bullets from 90 to 110 grs, but if you want to try that data using 748, I would use the minimum charge listed and see how the velocity from your rifle compared to the published velocity for H-335.
As stated above 748 is too fast burning for the .270 Win, what this means using Quickload is with a 130 grain bullet the case would be 80% full when max chamber pressure is reached.
If 760 were used the case would be 93% full at max chamber pressure with the same bullet.
If IMR-4350 were used the case would be 99% full at max chamber pressure with the same bullet.
Bottom line, you want the case to be 86% to 100% full (load density) for the best efficiency and accuracy and with 748 there would be too much air space left in the case for good efficiency.
If 760 were used the case would be 93% full at max chamber pressure with the same bullet.
If IMR-4350 were used the case would be 99% full at max chamber pressure with the same bullet.
Bottom line, you want the case to be 86% to 100% full (load density) for the best efficiency and accuracy and with 748 there would be too much air space left in the case for good efficiency.
I'm hesitating to post this, but here goes. It may not be the most ideal a powder to use for your intended purpose, but that does not mean that it will not/can not work effectively. Just for example, in coming up with reduced loads for a bullet test I'm working on, I used BLC-2 (ball powder slightly slower than 748) in my 270 wsm. It is far from an ideal powder, all the flaws mentioned above would be equally applicable to this cartridge/powder, and any flaws would be further amplified by the larger case volume of the WSM. But low and behold, using some common sense and a reasonable starting load, I got velocities between 2000 and 3000 FPS for most bullets between 100 and 130 Grains. While I was working up a reduced load with 110 Gr Hornady HP's, a 3-shot group was cloverleafed, all touching @ 100.
So, again, it may not be the best choice for your application, but if someone with quickloads runs some pressure estimations and you start low, you might be pleasantly suprised at what you find. Keep it safe, and you have nothing to lose. I would stick to bullets 130 Gr or lower if you do decide to use it, and don't push it for max load, the velocity spread in a fast burning powder and half empty case can vary quite a bit. Here is a breakdown of some of the velocities/charge loads I got using BLC-2, your results with 748 would probably be somewhat similar:
110 Gr Hornady HP, Federal 215M primer, Winchester brass:
43.5 Gr BLC-2: 2644 FPS
44.5 Gr BLC-2: 2668 FPS
45.5 Gr BLC-2: 2759 FPS
46.5 Gr BLC-2: 2880 FPS
47.5 Gr BLC-2: 2934 FPS
48.5 Gr BLC-2: 2963 FPS
Still no pressure signs at this load, I had no reason to go higher though. A fast powder like these will be much better suited in light varmint bullets than any big game-capable bullet.
I only tried 1 load with 130 Gr bullets: Sierra 130 Gr BTSP, Federal 215M, Winchester brass, 33.0 Gr BLC-2: 2135 FPS. I ended up using a slower powder for reduced loads in this weight, so can't comment on how effective it would have been. I don't believe you'll have success with a 150 grain bullet load. Be careful when treading outside the scope of a loading manual (or simply don't do it), and friends with quickloads will save you a lot of time working up from extremely low charges, without worrying about losing appendages. Contrary to what many people believe, loading extremely low charges is not risky, so long as you don't end up with a squib. And it beats starting off too hight. YMMV
So, again, it may not be the best choice for your application, but if someone with quickloads runs some pressure estimations and you start low, you might be pleasantly suprised at what you find. Keep it safe, and you have nothing to lose. I would stick to bullets 130 Gr or lower if you do decide to use it, and don't push it for max load, the velocity spread in a fast burning powder and half empty case can vary quite a bit. Here is a breakdown of some of the velocities/charge loads I got using BLC-2, your results with 748 would probably be somewhat similar:
110 Gr Hornady HP, Federal 215M primer, Winchester brass:
43.5 Gr BLC-2: 2644 FPS
44.5 Gr BLC-2: 2668 FPS
45.5 Gr BLC-2: 2759 FPS
46.5 Gr BLC-2: 2880 FPS
47.5 Gr BLC-2: 2934 FPS
48.5 Gr BLC-2: 2963 FPS
Still no pressure signs at this load, I had no reason to go higher though. A fast powder like these will be much better suited in light varmint bullets than any big game-capable bullet.
I only tried 1 load with 130 Gr bullets: Sierra 130 Gr BTSP, Federal 215M, Winchester brass, 33.0 Gr BLC-2: 2135 FPS. I ended up using a slower powder for reduced loads in this weight, so can't comment on how effective it would have been. I don't believe you'll have success with a 150 grain bullet load. Be careful when treading outside the scope of a loading manual (or simply don't do it), and friends with quickloads will save you a lot of time working up from extremely low charges, without worrying about losing appendages. Contrary to what many people believe, loading extremely low charges is not risky, so long as you don't end up with a squib. And it beats starting off too hight. YMMV
