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View Full Version : 30-150-TL-PB in my SKS (Type 56)



Maven
11-14-2007, 06:06 PM
I just returned from the range after testing 20 rnds. of the Lee group buy CB in my "as issued" SKS. Although the results were mixed, they were encouraging since 10 shots went into a 2.25" x 2" group @ 50 yds. with two groups of 4 shots that you could cover with a dime. That's the good news. The bad news is the extreme spread was 7.5" (will try to post a photo tomorrow). Since I didn't know where to begin with the group buy bullet, I chose 8gr. of Unique and seated the unsorted & unweighed CB's to 2.19" OAL by letting the action seat a CB in a dummy round. Btw, I used a .314" H & I die to lube the CB, which barely touched it and a Lee die to crimp the loaded round.

Excuses/whining: The 2" red dot was too small for me to get the best sight picture on a very gray day, even when wearing yellow shooting glasses. Two of the cases had neck splits produced by over-expanding them in the M-die. Those splits may have produced the 2 low hits on the target. However, I'm wondering whether 8gr. of Unique was appropriate since it didn't operate the action at all and left the cases pretty dirty. On the other hand, there was minimal bbl. leading and none in or on the gas piston.

Next step: Retesting with both 12gr. & 13gr. of WC820, since they will cycle the action most of the time (12gr. will cycle it maybe half the time) and sorted CB's. I.e., my mold produces 2 different bullet weights (~140gr.): Cavities 1 & 2 -> CB's that are slightly lighter than cavs. 3 - 6. I'd heat-treat the CB's too if our oven were more reliable (doesn't say much for Maytag's digital control!). Unfortunately, retesting will have to wait until mid-December as our range will close on Saturday for deer season.

Maven
01-07-2008, 06:07 PM
Weather and other committments kept me from retesting the group buy CB in the SKS until this afternoon. The load was 12gr. WC 820 + WLR primers + unsized and tumble lubed group buy CB's seated to an OAL of 2.19" Results were varied in that it certainly is possible to put 5 of them into 1" @ 50yds., but then again, it is also possible not to. I.e., if I swabbed the bbl. after every 5 shots, I could have removed the leading that built up. It wasn't a heavy coating, but enough to materially affect accuracy. By way of comparison, my LBT gas checked CB's (C.E. Harris' design, essentially the same as the Lee & Lyman offerings but "fat" enough for me to size to .314") using 14gr. WC 820 went into a ~1" group at the same distance, with no perceptible bore leading and none on the gas piston or port. In sum, there's too much fiddling to do to get this CB to shoot well in my SKS and will probably not try this again. In the .30-06, definitely, but not the SKS.*




*Our oven is a gas-fired digitally-controlled Maytag (7yrs. old) that doesn't maintain temps. well, even after Maytag authorized service. Ergo, heat-treating isn't really an option, nor is purchasing another Maytag product for that matter.

PatMarlin
01-08-2008, 03:34 AM
I enjoy your research on the boolit Maven. Feel like I'm making progress with my copy sitting on the shelf and reading your posts even though I haven't casted a single boolit yet... :mrgreen:

Maven
01-08-2008, 04:34 PM
Pat, That mold and its droppings are definitely a work in progress. Lapping the cavities, though very tedious,* helped a great deal. Finding the right powder/velocity for 3 different rifles (.30-30, Marlin #336; .30-06, Mod. 70 Win.; Type 56 SKS) has been "interesting" as well. I.e., the .30-30 & SKS were the most difficult to get to shoot reliably. Of the two, the SKS was the better performer and I have no doubt that I could get it to put 5 into 1" @ 50yds., with it, but I'd have to move heaven & earth to do so. The .30-06, was also a bit of a problem child until I dropped the powder charge to ~9gr. Unique. Tapering the CB's, which was labor-intensive, payed off, but isn't in keeping with the idea of a plinker CB. My next outing with 30-150-PB (unsized) will be in my super accurate Mod. 28/30 Finn. Nagant with the same ~9gr. Unique charge as in the '06. I'm hoping the results will be rewarding.


*You have to cast & segregate at least 3 CB's/cavity and either drill & tap them or drill and use a coarse threaded drywall screw with the head cut off to spin them in each cavity. A lathe or drill press would be ideal for this, but alas, I don't own either.

PatMarlin
01-08-2008, 06:19 PM
Yea I'll have to get going with mine. I bought my wife a beautiful little Browning BLR Lightening in .308 win. for Christmas. Cleaned the bore bare and slugged it and it's about .3085 goove diameter.

I'm thinking this boolit maybe a good candidate for the rifle, and since I had planned to work her into more shooting with light loads, it just may be the ticket.


Anyway keep up the posts Maven, and I'll jump in and join ya soon as I can... :drinks: