Originally Posted by Iowegan
It appears I will not get an answer to my question in post #41 so I will answer it myself.
. . .When I reload 223 Rems or 308 Win ammo on my Dillon RL550 progressive, there is absolutely no difference than when I load them on my Rockchucker single stage. The finished product looks and shoots equally well from either press. . . . I rarely shoot over 250 yards but accuracy is the same from either press out to 250 yards. I think if there was going to be an accuracy issue, it would show up before 250 yards???
The reason for using a single stage press for rifle ammo is more for convenience not quality. . . .
Yes, the gains are *mostly* for convenience but there's at least one physical difference in the output. Whether it's important to you, or important at all, is certainly a judgement call you've clearly made. And I take no issue with that for your use.
But with slop both in the toolhead and in the subplate (due to varying pressures elsewhere around the press), there's an inconsistency in bullet seating depth on a progressive that will not occur on a single stage press.
Others report a difference in concentricity (bullet seating) between progressives and single stage. I use Hornady presses, and I cannot personally confirm a difference. But then again I chose the Hornady AP in part because it has no slop at the toolhead. I've never used a Dillon.
IME, the rest can legitimately be labelled "convenience" items, but I think it's a bit unfair to do so.
EG, one is unlikely to hand weigh each powder charge on a progressive. One is also unlikely to adjust bullet seating for each cartridge to achieve "identical" BTO lengths. And if one did choose to operate a progressive using a single-stage process, it's certainly far less convenient than using a single stage in the first place. But convenience for bulk ammo is why we buy progressive presses, isn't it?
Whether by choice of rifle or caliber or available shooter skill or goal, most of the differences are likely not visible out to (I'd guess) 300 yds. There a (eg) 50fps MV variation on a 168gr 308 projectile gives only ~0.75" change in drop and almost no change in windage.
Unless you get outside your load's sweet spot . . . which is easier to do on a 25gr 223 charge than a 43gr 308 charge.
So I certainly don't take factual issue with what you say . . . but I don't think it gives full justice to normal single stage precision work, let alone to the neck-turning, neck tension, bullet sorting crowd lol.