First, let me say that I already have the Explosion Shield on my Loadmaster. I figured as much money as I have spent on reloading equipment and components, I could not even comprehend not being willing to spend $4.99 for the explosion shield. It is cheap insurance for all Loadmaster owners and every owner should install one regardless of primer brand. Over the years in various gun forums, I've read of
every brand of primers having a primer pop -- it is not magically limited to only Federal.
Maybe a bit difficult to see here, but the tray is tilted at around 45 degrees upwards and towards the press.
This actually prevented me from having to dig out the primer anvils out of my face, but my point is that if there is any kind of blast protection then it would have to cover the entire priming system to be completely safe.
This makes me wonder if the Lee blast shield is more of a liability waiver than an effective device to prevent serious damage and/or accident.
I see that you misunderstand how it works, which is easy to do for anyone who hasn't seen it in action. Once you get one (and you
will get one, right?), it will become clear how it works.
A small pistol primer pocket depth is .118" to .122". Since the Loadmaster seats the primer at top of ram stroke, the explosion shield only needs to be positioned to protect during the last .118" of ram movement. It is in the correct position and completely shields me from the primer tray during that critical moment that primer insertion occurs.
There is zero downside to using one.
If you put the sizing die in station 2 you will have a problem; you firstly lose the possibility to de-prime in that station and secondly your die will never go as far down as it can in station 1 because of the small plastic lever in the priming system that every rotating case triggers once it passes it. If you set it as low as in station 1 you will crush that lever and you will not be able to prime.
My idea is to have an empty (minus the de-priming pin) sizing die in station 2 positioned above this plastic lever, but still as far down as possible so that it centers the case as much as it can. Since for 9x19 the sizing die is conical it won't be 100% centered after station 1, but it will be better than nothing at all.
A better approach is to purchase a Lee Universal Decapping Die for station one, and then remove the decapping pin from your sizing/decapping die to install in station two. That is how I and many other Loadmaster owners (but not all owners) run the press.
As mentioned, you have a slight misunderstanding on how the primer lever movement would be affected. At the bottom of ram stroke, the shellplate indexes. The case moving from station 1 to station 2 pushes on that curved arm as it passes by, pushing the primer lever over get the next primer into position. Then, in the last two inches of upward ram movement, that pin pushes the primer lever back over to push the slider with primer under the case. Having a die in station 2 has zero impact on this movement.
Lee standard instructions, IIRC, are to screw the sizing die in until it touches the shellplate, then back the ram off and screw the die in another quarter turn. Personally, I leave the die just touching the shellplate as I want the shellplate deflection to be even across all the die stations.
The big issue I am having (may post pics of it someday) are loose powder grains - I use N330 that has stick powder, that is quite sticky and like to hang on even to dry and clean surfaces - that get stuck inside the rim of the indexing wheel. This prevents the brass from being where it should be and thus the primers get misaligned. I will however solve this by cleaning the rims of the indexing wheel perhaps every 50 rounds, and get a die to center the cases better.
Yes, a dirty shellplate can be a definite issue. But why are you getting loose powder?
If I am loading a really fine powder like AA #7, then I will get some loose grains into the press area. But a stick powder leaking seems surprising to me.