-
ODT Gun Show & Swap Meet - May 4, 2024! - Click here for info
208gr ELD over RL-17 in .308 Win?
- Thread starter whiskeydeltatango
- Start date
Well... in 2012 I read an article in Handloader magazine, calling the seating depth/pressure thing a myth. Claiming it did not affect pressure significantly in bottle-necked cartridges with modern rifle propellants. Take that for what it's worth-- the article convinced me, and I've not worried about it since-- unless I'm on the lands, which DEFINITELY DOES affect pressure significantly.
I'll say this again: that article was talking about BOTTLENECK RIFLE CARTRIDGES ONLY. Straight walled rifle cases-- and any pistol case-- seating depth has a significant impact on pressure. Do your own research; maybe that article was wrong.
I'm going to guess that you'll run out of room for powder with the shorter seating. Since you're asking this question, I'll going to guess you've never played that game... get a long drop tube, and slowly pour in the powder. You can get probably 2 more grains in that way as opposed to just dumping it in. You can achieve the same thing by mostly filling up the case, then tapping it on a table 20 times, and then adding the rest of the powder, but that's time consuming. Having a little "crunch" is ok-- you'll feel it when you start crushing the grains together. A little is OK; a lot is not. If you're worried that you have too much-- caliper the OAL of the cartridge, then wait 24 hours. If it hasn't grown longer (powder pushing out the bullet), then you are probably OK.
You're trying to hotrod the cartridge without giving it room for the extra powder, and extra powder is the key to RL17's higher velocities-- it doesn't have more energy per mass or anything. Just a flatter burning curve. Long drop tube and whatnot may get you part way there, but realistically consider single-loading overlength rounds, which is not a big deal.
I'll say this again: that article was talking about BOTTLENECK RIFLE CARTRIDGES ONLY. Straight walled rifle cases-- and any pistol case-- seating depth has a significant impact on pressure. Do your own research; maybe that article was wrong.
I'm going to guess that you'll run out of room for powder with the shorter seating. Since you're asking this question, I'll going to guess you've never played that game... get a long drop tube, and slowly pour in the powder. You can get probably 2 more grains in that way as opposed to just dumping it in. You can achieve the same thing by mostly filling up the case, then tapping it on a table 20 times, and then adding the rest of the powder, but that's time consuming. Having a little "crunch" is ok-- you'll feel it when you start crushing the grains together. A little is OK; a lot is not. If you're worried that you have too much-- caliper the OAL of the cartridge, then wait 24 hours. If it hasn't grown longer (powder pushing out the bullet), then you are probably OK.
You're trying to hotrod the cartridge without giving it room for the extra powder, and extra powder is the key to RL17's higher velocities-- it doesn't have more energy per mass or anything. Just a flatter burning curve. Long drop tube and whatnot may get you part way there, but realistically consider single-loading overlength rounds, which is not a big deal.
You should spend the $ and get the Quick Load software... This will open your eyes to a lot of internal ballistics principals. Cartridge pressure has a lot to do with case internal volume. Seating the bullet deeper results in a lesser internal volume increasing pressure.
Sent from my iPhone using Tapatalk
Sent from my iPhone using Tapatalk
There is no doubt that reduced volume will have an effect on pressure. The question is how much? In a bottle necked cartridge such as a .308, is seating 0.04" deeper going to have much effect? From a % standpoint of the total volume, just how much has it been reduced? Probably not much and most likely insignificant when starting at minimum load. Whereas in straight walled pistol cartridge, it is going to be a larger percentage of reduction for sure as the total volume is significantly less to start with and the bullet diameter takes more volume % wise than the rifle cartridge.
Rosewood
Some powders are affected by volume change more than others. True safe when starting at a min load. True on pistol cases having a more drastic effect due to larger percentage numbers. Sound like we agree on a lot.
Sent from my iPhone using Tapatalk
Sent from my iPhone using Tapatalk
does anyone have quickload that can run the data?
cant really drop 153 bones right now on the software..
cant really drop 153 bones right now on the software..
I am with you. I would love to have that software, just can't justify that kind of cash for it.
I bet if they dropped the price to say $30 they would sell 10 times the copies and would ultimately make more money on it.
