7TCU & 7-30 Waters data

[Alan4620]

Anyone out there have any cast bullet data for 118 grain cast bullets in 7 TCU & 7-30 waters?

All I can find is for 139 grains and up.
Just looking or target loads.

Thanks

Alan

[MnMike]

There are loads as you say for heavier bullets. Normally you could say that these would be safe in a lighter bullet, and they are. The problem comes with leading and poor accuracy. Lead is softer than copper and may not take the velocities without skipping over the rifling, clogging your barrel, and not getting a good enough spin for accuracy. If you lower the powder charge to cut the velocity, you risk other things that I don't completely understand.

I only shoot lead in pistols and I guess I'm not much help- good luck,

mike

[jhalcott]

  Alan ,you don't say what length barrel you are using. I used the lowest charges for a 120 grain jacketed loads in MY T/C barrels and have had excellent luck so far! I had to change to a different lube to get rid of leading in the 7-30 barrel though. I am using an alloy that is nearly identical to Lyman #2 (15-16 BHN) and Hornady gas checks. The Hornady manual lists 120 grain loads for both rounds.

[Alan4620]

Sorry I have a 10" 7TCU and a 14' 7-30 Waters.I can find jacketred data,but nothing for less than 139 grain lead bullets. Can I use Jacketed starting loads fior a safe lead load of equal weight?

I loaded 5 7TCU's with 16 grains of IMR 4227 will this be safe? I don't want to under load as some loads warn against this.15.5 grains is what the T/C load book says for a 139 grain lead start load.I believe a jacketed 120 was 18 grains to start.

I don't mind lousy shots,but safty is a concern.  I must be chicken because my first shot with a new load is with a 6x6 post between me and the T/C.

Any suggestion?
Alan

[GrampaMike]

Hello Alan,

No Loads for 7mm TCU

Loads only for 7-30 Waters 14” TC Barrel.
Hard Cast Lead 118gr with Gas Check.
Loaded to 28,000 PSI (MAX PSI for 7-30 Waters is 50,000)
Case Trim: 2.030
C.O.L.: 2.567

From Most Accurate to Least Accurate in my 14” TC Barrel

31.4 gr. VihtaVuori N135     2027fps     94% Load Density
31.7 gr. Accurate 2495       2048fps     91% Load Density
30.3 gr. IMR-3031              2048fps     88% Load Density
28.4 gr. VihtaVuori N133     1977fps     85% Load Density
31.3 gr. VihtaVuori N140     1999fps     89% Load Density
33.5 gr. Accurate 4064       2041fps     98% Load Density

These are my SWEET spots, good luck with yours.

16.0 gr. of IMR-4227 is ONLY 48% Load Density and 13,800 PSI.

Mike

[jhalcott]

Lyman #47, page 436 shows Jacketed loads in a 10" 7TC/U barrel.
  min                                 MAX
2400/15.2=1523 fps         19.5=1999 fps
imr4227/16.0=1444           20.5=1957
imr4198/18.8=1564           23.5=2012,compressed load
RX7/20.8   =1719               26.0=2108
  Since lead is softer than jacketed bullets ,these velocities MAY be a few feet slower than you will get. I believe they will be safe IF you start at the minimum and work up.