Kevin Stenberg
Well-Known Member
Has anyone intentionally used Cu in there alloy to push there plain based bullets close to the speed of standard checked bullets?
Cu in plain based bullets
- Thread starter Kevin Stenberg
- Start date
RBHarter
West Central AR
I didn't realize that it was a big deal , or that I've probably always done it , but I have several that will actually outrun the jacketed counterparts , 30-30 and 32 Rem . Both at start loads with IMR 4350 are close to or exceeding jacketed maximum speeds ......I'm at 4000' with 17% humidity and uncorrected we hover around 27.5 inhg and my Chrony has been questioned all 3 give the same numbers so what do I know .
Yes, it works. BO, 30/30, haven't tried the 308W yet. 145gr @ 2100 in the BO carbine, 175gr @ > 1600 in the 30/30 so far. About all the recoil I can take with the 30/30 on the bench. 175gr works good in the BO pistol, just haven't chronyd yet. Bama ran his 358(?) @ 300 yds, pretty fast with excellent accuracy, Cu added. Cu adds the toughness to take the high RPM. I've dropped a percent of Sb & get good results, trying lower, I think the 30/30 is running ~ 1% now.
Kevin Stenberg
Well-Known Member
The reason I ask. Most posts concerning a Cu alloy also include GC when trying to attain higher than average cast velocities.
All of my Sn comes from pewter so I always have some percentage of Cu in my bullets. And was hoping I could get by with out the checks.
All of my Sn comes from pewter so I always have some percentage of Cu in my bullets. And was hoping I could get by with out the checks.
RBHarter
West Central AR
I run PB for the 32 Rem and run 2 gr of IMR 4350 under the 170 jacketed data for the 32 WS with a plain based 325-170(175)@ 176gr and it goes about 2150 fps or about 50 fps under the max load . See disclaimer above. I dont recall which I used PB in the 30-30 but the Cramer #45 is getting there in a hurry over start plus jacketed load for a 150 gr jacketed of H322 . I have a 6.8 SPCII that by best guess is running around 42kpsi with a 130 gr NOE 279-124 (it's the only dedicated mould for that cartridge) at 2050 fps . Similar results are had with the NOE 225-55 @ 62 gr and 2600+ in 222 and 223 . A 358 Win in a 14 twist runs a 250 2100 fps as well . 1 alloy derived from WW and GI tamper seals . When the seals that appear to be 1-20 are rendered the copper wire they are on gets stirred in down and skimmed . Copper is the only answer for the ability of this alloy to do what it does . I've gone over 2400 without leading but the groups weren't there in the 6.8 . The 358 while not Chrony'd would drop the floor plate open during recoil with an inside the bow release on a 98 clone . No fouling or groups but plenty of go fast . The single game application resulted in an identical wound track to a 150 SPBT Hornady but 900 fps slower . Those five in my avatar are dry powder clay catch the 200 gr start weight of those finished at 196-7 gr and at about 1650 fps impact speed are .610 -.618 I believe .