On the lyman blocks there may not be enough extra for good alighnment and seal of the pin. The 457 125 dosnt have a lot of extra block below the nose. I converted the Lyman Postell mould to nose pour years ago at work. It can probably be done though. In the manner of the hoch or ballard blocks. One thing Ive noticed on my adjustable paper patched mould is that the nose length stays the same and driving surface gets shorter. This is a PP mould so may not be as important as a grease grooved mould. It can be done and while not really hard to do set up is going to be very important to recatch all the existing surfaces. A floating pin and mount will need to be made up these are normally a piece of flat stock with a tapped hole and 2 slots held to the blocks with shoulder bolts. This allows the blocks to open and close and the pin to self alighn into the cavity. One plus is if the nose is adjustable as you show round nose flat point and hollow point inserts could be made. If base adjustable flat based Gas checked cup base or hollow base pins can be made.
Like almost any project, it can be done. The problem will be the cost of a good machinist. If additional nose length is desired, the machinist can pin additional block halves in the form of flat stock can be rigidly pinned to the bottom and an accurate cut can be made. The plug holders can be made from aluminum and that seems to dissipate heat faster and increase the ease of casting with the #125 which has too much volume for the block size. Look at castpics/The Mould from Hell and you can see how we approached the modification of a 358315 Lyman. May give you some ideas./beagle
diplomacy is being able to say, "nice doggie" until you find a big rock.....
I thought the illustration was self explanatory... perhaps it is not.
the concept is to make a blunt nosed muzzleloading bullet that is adjustable in length.
To do this the long nose of the 457125 design would be made into a full bullet diameter straight cylindrical shaft extending out the bottom of the blocks the same as with a typical hollow base mold. This would hold the adjustable length plug. The business end of the plug would be for a blunt nose (as opposed to hollow base).
This is all as shown in the picture.
To summarize, the front driving band of the bullet would be extended out of the bottom of the blocks.
An adjustable length plug would be supplied to form the WFN profile.
The simple way to do jobs like this is to make a block with an arbor hole..(all square and precise).....clamp block on machine table,centre spindle on arbor,clamp mold blocks on arbor,bore thru from blind side.....the arbor is made to suit for each job........if the lube grooves are regular,locate there,....otherwise arbor will need to look like a bullet and locate on major dia. ......you can also make the nose plug split,same as a bullet mold,.....a very straightforward job for a beginner.
BP | Bronze Point | IMR | Improved Military Rifle | PTD | Pointed |
BR | Bench Rest | M | Magnum | RN | Round Nose |
BT | Boat Tail | PL | Power-Lokt | SP | Soft Point |
C | Compressed Charge | PR | Primer | SPCL | Soft Point "Core-Lokt" |
HP | Hollow Point | PSPCL | Pointed Soft Point "Core Lokt" | C.O.L. | Cartridge Overall Length |
PSP | Pointed Soft Point | Spz | Spitzer Point | SBT | Spitzer Boat Tail |
LRN | Lead Round Nose | LWC | Lead Wad Cutter | LSWC | Lead Semi Wad Cutter |
GC | Gas Check |