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Posted: 5/1/2015 8:37:16 PM EDT
| You folks with short barrels (doesn't matter on caliber) find heavier bullets shoot better or no difference? My concern is wasted powder (fireball). I have a 10.5 inch 308. With a heavier bullet and same velocity as a smaller bullet same velocity, there is less powder used when reloading. May be over thinking this but thought I would ask. I normally shoot 150 gr hornady fmj with no problems. Picked up some 180 gr hornady interlock BTSP recently to try. Difference is about 3 gr or more of powder for same velocity on each (according to hornady reload manual). Again, may be over thinking this. Thanks |
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I'm not sure I agree with your premise, or maybe I am misunderstanding you? Are you saying that a heavier bullet can be driven to the same velocity using a smaller volume of a given powder? That has not been my experience.
The truth (IMO) is that SBRs waste powder. A powder fast enough for 100% burn in a 10" barrel is probably not safe for use in a .308 (ie, it would be a pistol powder or something). |
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Here is an example to hopefully help what i am getting at. Getting this info from hornady reloading manual.
180 gr bullet - varget - velocity 2000 - 32.0 gr 150 gr bullet - varget - velocity 2300 - 35.9 gr by going to a heavier bullet but drop velocity, I will burn less powder. May not seem much. Again, I may be over thinking this trying to reduce powder loss. Make sense? |
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You're overthinking it. The heavier bullet has a reduced max load because it fills more of the case. You could just as easily load the 150gr bullet with 32gr of powder as you could the 180gr bullet, and it will go faster than the 180gr bullet too. You can keep on reducing the powder until your gun doesn't cycle if you want to. But you're still going to be wasting powder, because none of the powder designed for .30cal rifle use are going to achieve 100% burn in a 10" barrel, AFAIK.
If your goal is to use less powder in your reloads, just use the same bullets you are now and reduce the charge a bit, say 10%. It will still probably cycle. If you're worried about losing unburned powder out the muzzle when you shoot, you shouldn't have bought a 10" .308. |
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