Re: Oh Boy, Gonna Get Busy With the Lee Slugs
Posted: 28 Oct 2018 06:28
Been a while, but I haven't given up. I put this on hold while I prepped my centerfires for hunting season.
Honestly, I'm scratching my head. I bought the components that match the BPI recipe, and like the Lee data, the stack doesn't work out within the confines of the hull. It's been a very frustrating process.
Yesterday, I went back to the bench on my own and will try to take a few days to work it out. I doubt the Lee slug is going to deliver 2.5 MOA I'm asking. They will shoot through the same hole at 25-yards, but you need a yardstick to measure the groups at 50-yard. Just to take a guess out, the same hole at 25-yards is not an important measure as my Mossberg 500 with a cylinder barrel shoots them the same.
Off and on over six years, I've spent a similar amount of time with this and never reached a successful conclusion. I've also spent a lot of time on the search forums and youtube but never seen anyone come up with a successful measured conclusion. It seems most are happy just solving the column stack and I have never seen anybody post results that measure up to modern ammunition.
So far, this is what I've used to achieve my best results, 3.3 to 3.5 MOA. I said best, but not acceptable.
Oh, I figured out the magazine issue with the Lightfields! The previous owner must have taken it apart to clean it and reassembled it wrong! There is the limitation notice for the Marlin 512 Slugmaster in the period catalogs, but the Lightfields squeak by!
I plan to continue searching for an acceptable projectile that I can cast from home. The fellow that owns NOE Moulds is a friend of mine, and we reviewed the Lee Slug at length. It all comes down to the Key Drive pin design. It needs to be slightly shorter so that more lead remains in the nose of the foster design and it needs to have a slightly greater final outside diameter which will deliver a thinner skirt. Both of these changes would move the center gravity ahead of the center of pressure/lift. On a tabletop and if set on its side, the one-ounce slug would demonstrate the same characteristics of their 7/8-ounce slug. It would roll over on its nose. I also was going to change the "Key". Rather than cut the hollow base in half, I was going to make quarter the base with a "crosshair" key. This would support the column wad cup and eliminate the need for a card wad between the slug and cup.
The idea was that NOE would offer a replacement key pin for the existing Lee mold rather than cut a new mold. The snag is that the Lee Key is patented. Oh well.
NOE is going to start offering the Lyman style, the shuttlecock design, for both 12 Gauge and 410 Bore. He is going to be sending me the 12 Gauge in a few days for testing, but it will be a little late for my hunting trip.
I've been also pondering the Accurate 73-470S, a full-bore slug. It totally eliminates the column wad issue. Waxed Nitro over powder cards are used to obtain the length and a roll crimp is used to secure it in place.
I will see what today brings and report back.
Honestly, I'm scratching my head. I bought the components that match the BPI recipe, and like the Lee data, the stack doesn't work out within the confines of the hull. It's been a very frustrating process.
Yesterday, I went back to the bench on my own and will try to take a few days to work it out. I doubt the Lee slug is going to deliver 2.5 MOA I'm asking. They will shoot through the same hole at 25-yards, but you need a yardstick to measure the groups at 50-yard. Just to take a guess out, the same hole at 25-yards is not an important measure as my Mossberg 500 with a cylinder barrel shoots them the same.
Off and on over six years, I've spent a similar amount of time with this and never reached a successful conclusion. I've also spent a lot of time on the search forums and youtube but never seen anyone come up with a successful measured conclusion. It seems most are happy just solving the column stack and I have never seen anybody post results that measure up to modern ammunition.
So far, this is what I've used to achieve my best results, 3.3 to 3.5 MOA. I said best, but not acceptable.
- Hull length matches chamber length, don't create freebore with a shorter hull.
- The column wad petals are not to be longer than the start of the ogive radius of the slug. Trim them if needed. The nose of the slug must completely open the star crimp before the leading edge of the petals encounters the star.
- A 16 or 20 gauge card wad is needed between the slug and the column wad cup.
- Use a six star crimp vs. an eight.
Oh, I figured out the magazine issue with the Lightfields! The previous owner must have taken it apart to clean it and reassembled it wrong! There is the limitation notice for the Marlin 512 Slugmaster in the period catalogs, but the Lightfields squeak by!
I plan to continue searching for an acceptable projectile that I can cast from home. The fellow that owns NOE Moulds is a friend of mine, and we reviewed the Lee Slug at length. It all comes down to the Key Drive pin design. It needs to be slightly shorter so that more lead remains in the nose of the foster design and it needs to have a slightly greater final outside diameter which will deliver a thinner skirt. Both of these changes would move the center gravity ahead of the center of pressure/lift. On a tabletop and if set on its side, the one-ounce slug would demonstrate the same characteristics of their 7/8-ounce slug. It would roll over on its nose. I also was going to change the "Key". Rather than cut the hollow base in half, I was going to make quarter the base with a "crosshair" key. This would support the column wad cup and eliminate the need for a card wad between the slug and cup.
The idea was that NOE would offer a replacement key pin for the existing Lee mold rather than cut a new mold. The snag is that the Lee Key is patented. Oh well.
NOE is going to start offering the Lyman style, the shuttlecock design, for both 12 Gauge and 410 Bore. He is going to be sending me the 12 Gauge in a few days for testing, but it will be a little late for my hunting trip.
I've been also pondering the Accurate 73-470S, a full-bore slug. It totally eliminates the column wad issue. Waxed Nitro over powder cards are used to obtain the length and a roll crimp is used to secure it in place.
I will see what today brings and report back.