COWW and GC speed limit

[fatelvis]

I usually use straight WW alloy (sometimes with 95/5 added) and GCs for my rifle boolits. Assuming my boolits are sized .001" over groove and using 4759 and 5744, What velocity is a safely reached with this relatively soft alloy in say a 303, 30-40 or 30-06? Thanks-

[Tatume]

Hi Elvis,

I've been running LBT 270 grain LFN bullets in the 9.3x74R at 1800 fps using COWW with a bit of tin added for enhanced fill-out. More recently I've been using RCBS 35-200-FN bullets in the 358 Winchester at 2250 fps using 18 pounds COWW, a half pound of 50/50 solder, and one pound of linotype. I don't know if the linotype is needed or not, but it works so well I'm not about to change.

Take care, Tom

[btroj]

With those powders 1800 is pretty doable. Much more than that and you are better off with slower powders.

[Tatume]

Thanks, I should have mentioned that I'm using rifle powders.

[Tatume]

Here's some good discussion:

http://castboolits.gunloads.com/showthread.php?224655-Alloy-at-2200-fps

[Larry Gibson]

You can load a cast bullet to the maximum psi for any of those cartridges for a "velocity (that) is a safely reached". However, accuracy will be wanting at that level, especially with COWW alloy.

If you really want to know velocity with accuracy that can be achieved with those cartridges then read the sticky (listed above in this sub forum with the stickys') about the RPM Threshold. It explains the probable velocity levels and the reasons why.

btroj is essentially correct with the powders mentioned.

Larry Gibson

[popper]

Try adding shot (As) & W.D. for higher fps. It will also depend on the twist.

[fatelvis]

Thanks for the advice Guys. I especially like the RPM chart. Good stuff to know!!

[cbrick]

I routinely shoot 1900-2000 fps in both my 30-30 (1 in 12) and 308 (1 in 10) with 4759, air cooled CWW +2% Sn. No leading and shoots well.

Rick

[JeffinNZ]

2300fps in my .223 Rem.

[35 shooter]

I shoot straight wheel weight in my whelen but had to heat treat it to get the accuracy past 1800 fps. Even at 1800 it's better with heat treated. 4759 with a filler works great to 2200 fps and my brother gets 1900 fps with 5744 with a fliller and great accuracy in his whelen. Like btroj said it's all about the slower powders after 2200 with my rifle. I found a new (to me) load with 4350 the other day that should be 2400 fps plus with a 200 gr. boolit that has shot some clover leafs @ 100 yd. with the biggest groups so far of about
1 1/2 inches for 5 shots although i did get one group @ 2" out of ten groups.
Don't know about your other two rifles but your '06' should the same or better with those same powders. But if you want to shoot straight wheel weights you may have to heat treat.
When i started cast in a rifle a year ago i thought 2000 fps was the fastest you could shoot lead boolits with any kind of accuracy....... boy did i get an education in a hurry at cast boolits forum.:)