H380 in 338win mag 180g
- Thread starter chet
- Start date
DrMike
Ballistician
- Nov 8, 2006
- 37,181
- 5,645
Seems like an awfully fast powder, especially with heavier bullets. It will work, but I would think that slower powders would be preferable.
G
Guest
Guest
Looking over Hodgdon's online data, H380 is a great powder for lighter bullets, but once you get up above 200gr, you lose to the slower stuff like H414, Win760, and H4350. You'll give up 100fps in the 225gr bullet, and Hodgdon doesn't even list it for 250 & 275gr stuff. If you're shooting 180-200gr, it might be interesting, to say the least.
Antelope_Sniper
Handloader
- Jan 25, 2008
- 2,618
- 0
I've used some similar surplus powders in my .338 Win Mag with 200gr AB. Shot really well, but I was kind of worried about what the pressures might be, so I shelved the load.
I'd have POP run a quickload and see what it looked like.
I'd have POP run a quickload and see what it looked like.
- Nov 4, 2004
- 24,918
- 7,821
I am in agreement that H380 is pretty fast for the 338 WM. I also think you are better off with mid weight to heavy bullets in the 338 WM.
JD338
JD338
chet, H380 is worth a try with the 180 grain part. Hodgdon list it as very suitable with the light bullet.
Starting load is 65.0 grains for 2886 fps and a max charge of 72.5 for 3111fps and 51,100 cup.
This load is worth a try and let us know how she shoots. I have a 338 wm and I'm just starting to play with it. I have some 185 ttsx's loaded with ramshot hunter to try among other loads and recipes.
Give it a go and let us know. :grin: :grin:
P.S. IMR 4007 is also a good powder with this light bullet.
Starting load is 65.0 grains for 2886 fps and a max charge of 72.5 for 3111fps and 51,100 cup.
This load is worth a try and let us know how she shoots. I have a 338 wm and I'm just starting to play with it. I have some 185 ttsx's loaded with ramshot hunter to try among other loads and recipes.
Give it a go and let us know. :grin: :grin:
P.S. IMR 4007 is also a good powder with this light bullet.
- Thread starter
- #8
DrMike
Ballistician
- Nov 8, 2006
- 37,181
- 5,645
In a 22 inch barrel, a charge of 71 grains of H380 behind a 180 grain AB will burn 98.62 percent of the charge for a projected velocity of 3022 fps. A 24 inch barrel will burn 99.04 percent of the charge and produce a velocity of 3085 fps. I can't imagine why you would think that a shorter barrel will be beneficial for shooting. If it is a matter of convenience, by all means carry a shorter rifle. However, for maximum efficiency in the burn, you will want a longer barrel.
G
Guest
Guest
I believe Chet was more asking if his short barreled rifle might perform better with a faster powder than a slower one, just due to the faster powder burning more quickly, and thus not leaving as much "potential" unused versus a slower powder. In other words, will it lose less velocity per inch of barrel with a faster powder or will it lose the same velocity per inch of barrel as when using a slower powder? I don't know if there's credence in this thought line or not, but I suspect the barrel length will only dictate velocity and the size of the fireball depending on the charge you're using.
- Thread starter
- #11
DrMike
Ballistician
- Nov 8, 2006
- 37,181
- 5,645
dubyam,
I see what Chet is asking, but burn rate will not affect pressure requirements for the bullet to engage the lands. Pressure must reach a critical level in order for the bullet to engrave the lands. This effect is significantly a result of the burn rate. The barrel time for a 22 inch barrel is 1.023 ms and for a 24 inch barrel, 1.077 ms, which is a significant time differential. The pressure required to engrave the lands is constant whether the barrel is longer or shorter. Thus, whether the pressure is generated relatively quickly or is more gradual, the same critical pressure must be generated before bullet travel in the barrel occurs.
The differential in barrel time would indicate a sharper pressure curve over a shorter period of time with the H380 than that which is generated by a slower powder. In other words, there is a smaller volume of gas generated by the faster powder.
Again, whether the rifle has a short barrel or a longer barrel should not be the determinate in choosing a faster or a slower powder. I tend to like the shortest barrel time, everything else being equal. However, I must take into consideration the weight of the bullet I intend to use, the jump to the lands, and the intangibles (such as barrel harmonics, stiffness of the action, etc.) in choosing a powder.
On the whole, the faster powder will work for light for calibre bullets, but will likely prove unsuitable for heavier bullets in this case. In fact, Chet would need to drop back to significantly lower charges for a 225 grain AB. I would be uncomfortable using this powder with heavier bullets.
I see what Chet is asking, but burn rate will not affect pressure requirements for the bullet to engage the lands. Pressure must reach a critical level in order for the bullet to engrave the lands. This effect is significantly a result of the burn rate. The barrel time for a 22 inch barrel is 1.023 ms and for a 24 inch barrel, 1.077 ms, which is a significant time differential. The pressure required to engrave the lands is constant whether the barrel is longer or shorter. Thus, whether the pressure is generated relatively quickly or is more gradual, the same critical pressure must be generated before bullet travel in the barrel occurs.
The differential in barrel time would indicate a sharper pressure curve over a shorter period of time with the H380 than that which is generated by a slower powder. In other words, there is a smaller volume of gas generated by the faster powder.
Again, whether the rifle has a short barrel or a longer barrel should not be the determinate in choosing a faster or a slower powder. I tend to like the shortest barrel time, everything else being equal. However, I must take into consideration the weight of the bullet I intend to use, the jump to the lands, and the intangibles (such as barrel harmonics, stiffness of the action, etc.) in choosing a powder.
On the whole, the faster powder will work for light for calibre bullets, but will likely prove unsuitable for heavier bullets in this case. In fact, Chet would need to drop back to significantly lower charges for a 225 grain AB. I would be uncomfortable using this powder with heavier bullets.
I don't think anyone disagrees with you Dr. Mike. His original question is for the 180 grain bullet in the 338 win mag though. I have one and am curious of his results. IMR 4007 is also a fast powder and works well with the light bullets in the 338 winnie.
I just got me a 338 winnie and it is quite a learning experience. I'm used to smaller caliber magnums and the 338 does use faster burning powders quite efficiently. My smaller magnums use no faster that IMR 7828. This is a learning experience for me too. You know what I mean if you have a 338 winnie.
:grin: :grin:
I just got me a 338 winnie and it is quite a learning experience. I'm used to smaller caliber magnums and the 338 does use faster burning powders quite efficiently. My smaller magnums use no faster that IMR 7828. This is a learning experience for me too. You know what I mean if you have a 338 winnie.
:grin: :grin:
